Artykuły w czasopismach: „Fluorescent Nanoparticle”

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Nurgaziyeva, Elmira, Sarkyt Kudaibergenov, Grigoriy Mun i Vitaliy Khutoryanskiy. "Synthesis of fluorescently-labelled poly(2-ethyl-2-oxazoline)-protected gold nanoparticles". Chemical Bulletin of Kazakh National University, nr 1 (19.03.2021): 12–20. http://dx.doi.org/10.15328/cb1185.

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Gold nanoparticles (GNPs) protected by poly(2-ethyl-2-oxazoline) (POZ) of different molecular weights (Mw = 5, 50, 200 and 500 kDa) were synthesised and characterised by dynamic light scattering, nanoparticle tracking analysis, zeta potential measurement and transmission electron microscopy. It was established that the use of POZ with 50 kDa resulted in formation of GNPs with low polydispersity while POZ with greater molecular weights led to formation of more polydisperse GNPs. Fluorescent labelling of these nanoparticles was achieved through their reaction with polyethyleneglycol dithiol (8-12 kDa) as a linker molecule with subsequent reaction with 6-(iodoacetamido) fluorescein. The fluorescent nature of obtained GNPs was confirmed by the appearance of the fluorescence peak at 510 nm that is typical for fluorescein molecules and glowing of the aqueous solution under the UV irradiaton. The fluorescently-labelled GNPs are promising tool in biomedical application to monitor the biological systems using fluorescent microscopy.

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Sasaki, Isabelle, Jonathan Daniel, Sébastien Marais, Jean-Baptiste Verlhac, Michel Vaultier i Mireille Blanchard-Desce. "Soft fluorescent organic nanodots as nanocarriers for porphyrins". Journal of Porphyrins and Phthalocyanines 23, nr 11n12 (grudzień 2019): 1463–69. http://dx.doi.org/10.1142/s108842461950158x.

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Novel fluorescent organic nanoparticles made from citric acid and diethylenetriamine were used as biocompatible and highly water-soluble nanocarriers for hydrophobic tetraphenylporphyrin (TPP). The tetraphenylporphyrin units were covalently attached to the nanoparticles, generating conjugated nanoparticles which retain water solubility and preserve the photophysical properties of monomeric TPP. The conjugated nanoparticles show two distinct fluorescence features: blue emission from the nanoparticle when excited in the near-UV (360 nm) and characteristic far-red emission of the TPP when excited in the visible (Soret band or Q bands). The uptake of the conjugated nanoparticles in live human neuroblastoma cancer cells was evidenced using two-photon microscopy. These experiments demonstrate that the fluorescent organic nanoparticles do act as efficient nanocarriers, allowing cell internalization of hydrophobic porphyrins. These conjugated nanoparticles appear as promising nanotools for theranostic (based on the combination of imaging and monitoring of the nanoparticle fluorescence) and therapeutic (photodynamic therapy by selectively exciting the grafted porphyrin units) modalities.

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Dalavi, Dattatray K., Avinash Kamble, Dhanaji P. Bhopate, Prasad G. Mahajan, Govind B. Kolekar i Shivajirao R. Patil. "TNPs as a novel fluorescent sensor for the selective recognition of fast green FCF: a spectrofluorimetric approach". RSC Advances 5, nr 85 (2015): 69371–77. http://dx.doi.org/10.1039/c5ra09835a.

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The fast green FCF dye adsorbed over the surface of the CTAB stabilized tetracene nanoparticles (TNPs) forms a stable, non-fluorescent ground state complex and quenches fluorescence of nanoparticle sensor.

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Song, Xiaofang, Lifo Ruan, Tianyu Zheng, Jun Wei, Jiayu Zhang, Huiru Lu, Huiru Lu, Yi Hu, Jun Chen i Yanan Xue. "A Reduction Active Theranostic Nanoparticle for Enhanced Near-Infrared Imaging and Phototherapy by Reducing Glutathione Level in Cancer Cells". Journal of Nanoscience and Nanotechnology 21, nr 12 (1.12.2021): 5965–71. http://dx.doi.org/10.1166/jnn.2021.19514.

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Facile preparation of a tumoral-stimuli-activated theranostic nanoparticle with simple constituents remains a challenge for tumor theranostic nanosystems. Herein we design a simple reductionresponsive turn-on theranostic nanoparticle for achieving fluorescent imaging and phototherapy combination. The theranostic nanoparticle is prepared by a simple one-step dialysis method of reduction active amphiphilic hyperbranched poly(β-amidoamines) and a near-infrared (NIR) dye indocyanine green (ICG). The fluorescence of ICG is quenched by the aggregation-caused quenching (ACQ) effect. The fluorescent intensity of free ICG at 816 nm was ∼40 times as high as that of particulate ICG. After reductive nanoparticles incubated with dithiothreitol (DTT), the size of the nanoparticles increased from 160 nm to 610 nm by Dynamic light scattering (DLS). As nanoparticles were internalized by cancer cells, the disulfide bonds would be cleaved by intracellular reduction agents like glutathione (GSH), leading to the release of entrapped ICG. The released ICG regained its fluorescence for self-monitoring the release and therapeutic effect of ICG by fluorescence spectra and the quantitative evaluation of NIR fluorescence intensity. Remarkably, nanoparticles can also reinforce antitumor efficacy through photodynamic therapy and GSH depletion property. This study provides new insights into designing turn-on theranostic systems.

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Thompson, Shelby, Mychele Jorns i Dimitri Pappas. "Synthesis and Characterization of Dye-Doped Au@SiO₂ Core-Shell Nanoparticles for Super-Resolution Fluorescence Microscopy". Applied Spectroscopy 76, nr 11 (24.10.2022): 1367–74. http://dx.doi.org/10.1177/00037028221121357.

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Dye-doped nanoparticles have been investigated as bright, fluorescent probes for localization-based super-resolution microscopy. Nanoparticle size is important in super-resolution microscopy to get an accurate size of the object of interest from image analysis. Due to their self-blinking behavior and metal-enhanced fluorescence (MEF), Ag@SiO2 and Au@Ag@SiO2 nanoparticles have shown promise as probes for localization-based super-resolution microscopy. Here, several noble metal-based dye-doped core-shell nanoparticles have been investigated as self-blinking nanomaterial probes. It was observed that both the gold- and silver-plated nanoparticle cores exhibit weak luminescence under certain conditions due to the surface plasmon resonance bands produced by each metal, and the gold cores exhibit blinking behavior which enhances the blinking and fluorescence of the dye-doped nanoparticle. However, the silver-plated nanoparticle cores, while weakly luminescent, did not exhibit any blinking; the dye-doped nanoparticle exhibited the same behavior as the core fluorescent, but did not blink. Because of the blinking behavior, stochastic optical reconstruction microscopy (STORM) super-resolution analysis was able to be performed with performed on the gold core nanoparticles. A preliminary study on the use of these nanoparticles for localization-based super-resolution showed that these nanoparticles are suitable for use in STORM super resolution. Resolution enhancement was two times better than the diffraction limited images, with core sizes reduced to 15 nm using the hybrid Au–Ag cores.

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Atanasova, Milka, Yavor Ivanov, Elena Zvereva, Anatoly Zherdev i Tzonka Godjevargova. "Simultaneous Determination of Penicillin G and Chloramphenicol in Milk by a Magnetic Nanoparticle-Based Fluorescent Immunoassay". Open Biotechnology Journal 14, nr 1 (16.06.2020): 59–69. http://dx.doi.org/10.2174/1874070702014010059.

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Background: Antibiotic residues are a problem of increasing importance and have direct consequences for human and animal health. The frequent use of antibiotics in veterinary practice causes their excretion in milk in dairy cattle. This way, they can easily enter the human body through the consumption of milk and dairy products. Objectives: This induces the need for accurate and sensitive methods to monitor antibiotic levels in milk. The aim of this study was to develop a rapid and sensitive magnetic nanoparticle-based fluorescence immunoassay for the simultaneous detection of chloramphenicol and penicillin G in milk. Methods: Magnetic nanoparticles were synthesized and functionalized with (3-aminopropyl)triethoxysilane. Chloramphenicol-Ovalbumin and Chloramphenicol-Ovalbumin-Fluorescein-5-isothiocyanate conjugates were prepared. Penicillin G – ATTO 633 fluorescent conjugate was synthesized. Antibodies against chloramphenicol and penicillin G were immobilized onto the magnetic nanoparticles. The competitive fluorescent immunoassay was developed. The optimal concentration of the antibody-magnetic nanoparticles and the fluorescent conjugates for the assay was determined. The calibration curves for the antibiotics in buffer and milk were plotted. Fluorescent immunoassay for the simultaneous determination of chloramphenicol and penicillin G in milk was developed. Results: The limit of detection by the simultaneous immunoassay of chloramphenicol and penicillin G in milk was 0.85 ng/mL and 1.6 ng/mL, respectively. The recovery of different concentrations of chloramphenicol and penicillin G in milk samples varied from 98% to 106%. Conclusions: A rapid and sensitive magnetic nanoparticle-based immunofluorescent assay for the simultaneous determination of chloramphenicol and penicillin G in milk was developed. The magnetic nanoparticles ensured rapid and easy procedure.

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Singh Rana, Prem Jyoti, Pallavi Singh i Prasenjit Kar. "Carbon nanoparticles for ferric ion detection and novel HFCNs–Fe3+composite for NH3and F−estimation based on a “TURN ON” mechanism". Journal of Materials Chemistry B 4, nr 35 (2016): 5929–37. http://dx.doi.org/10.1039/c6tb00975a.

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Hollow fluorescent carbon nanoparticle and solid fluorescent carbon nanoparticle were synthesised separately fromSyzygium cuminiextractviaa self-catalysis method in large scale for commercialization without providing any external heat. The nanoparticles were charaterized and their applications studied.

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Hayashi, Terutake, Masaki Michihata, Yasuhiro Takaya i Kok Foong Lee. "Development of Nano Particle Sizing System Using Fluorescence Polarization". ACTA IMEKO 2, nr 2 (15.01.2014): 67. http://dx.doi.org/10.21014/acta_imeko.v2i2.108.

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<p>In order to measure the sizes of nanoparticles with a wide size distribution in a solvent, we developed an optical microscopy system that allows for fluorescence polarization (FP) measurement and optical observation. This system allows the evaluation of nanoparticle sizes over a wide range, because the fluorescent signal intensity is independent of changes in the nanoparticle sizes. In this paper, we describe a fundamental experiment to verify the feasibility of using this system for different sizes of nanoparticles.</p>

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Hayashi, Terutake, Yuki Ishizaki, Masaki Michihata, Yasuhiro Takaya i Shin-ichi Tanaka. "Study on Nanoparticle Sizing Using Fluorescent Polarization Method with DNA Fluorescent Probe". International Journal of Automation Technology 9, nr 5 (5.09.2015): 534–40. http://dx.doi.org/10.20965/ijat.2015.p0534.

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Fluorescent polarization methods are used to detect complementary base pairing of DNA in biological fields. These methods work by measuring the rotational diffusion coefficient of Brownian motion of the fluorescent particles in solution. The rotational diffusion coefficient corresponds to the inverse third power of diameter according to the Debye-Stokes-Einstein equation for nanoparticles as hard spheres. We develop a novel method to measure the rotational diffusion coefficient using a fluorescent probe with a DNA spacer connected to a gold nanoparticle. We studied the physical characteristics of this probe to verify the feasibility of the proposed method. The rotational diffusion coefficients of gold nanoparticles with diameters ranging between 5–20 nm were measured using this developed system. In this manuscript we describe a novel fluorescent polarization method for nanoparticle sizing using a fluorescent DNA probe.

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Jenie, Aisyiyah S. N., Fransiska S. H. Krismastuti, Yudia P. Ningrum, Anis Kristiani, Mutia D. Yuniati, Widi Astuti i Himawan T. B. M. Petrus. "Geothermal silica-based fluorescent nanoparticles for the visualization of latent fingerprints". Materials Express 10, nr 2 (1.02.2020): 258–66. http://dx.doi.org/10.1166/mex.2020.1551.

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The development of silica nanoparticles from the waste of geothermal power plants and their subsequent modification using a fluorescent dye, rhodamine 6G (R-6G), has been reported. The optimum specific surface area of the silica nanoparticles before modification was 289.2 m2 g–1. After modification, the intrinsic properties of the fluorescent silica nanoparticles were studied, and the results showed that they were in their amorphous phase, with a particle size of 5–10 nm. We proposed that the interaction between R-6G and the silica nanoparticle surface was due to the hydrogen bonding, using the results from the Fourier transform infrared spectroscopy. The obtained fluorescent silica nanoparticles had excellent fluorescence enhancement of 2-fold compared to R-6G in its original state. This study reports, for the first time, the synthesis of fluorescent nanoparticles from geothermal silica and its ability to visualize latent fingerprints on different smooth dry surfaces, making it an excellent candidate for fluorescent powders in forensic applications.

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Na, Young Joo, Sang Joon Park, Ji Hyeon Kim i Jong Sung Kim. "The Preparation of Fluorescent Nano Dye-Silica Particles by Sol-Gel Process". Solid State Phenomena 124-126 (czerwiec 2007): 651–54. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.651.

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The core-shell structure of dye-silica nanoparticle has been prepared. The dye-silica nanoparticle can be used as a substitute of fluorescent dye for bio analysis. The hybrid organicinorganic nanoparticle was prepared by sol-gel process using organic modified silane as the coupling agent for flourescent dye and silica. The size of the particle was about 50 nm, which was measured by DLS and confirmed by SEM photograph. The fluorescent dye (fluorescein-5-maleimide) was reacted with (3-mercaptopropyl) trimethoxy silane to produce dye-silane compound, followed by the sol-gel reaction with tetraethoxysilane(TEOS) and water to produce core-shell structure. The fluorescent spectrum showed that the fluorescent intensity of dye-silica nanoparticle was higher than that of fluorescent dye.

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Rex, Rachel, Soumik Siddhanta i Ishan Barman. "Role of Aqueous-Phase Calcination in Synthesis of Ultra-Stable Dye-Embedded Fluorescent Nanoparticles for Cellular Probing". Applied Spectroscopy 75, nr 8 (12.07.2021): 1012–21. http://dx.doi.org/10.1177/00037028211027597.

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Fluorescence imaging is a major driver of discovery in biology, and an invaluable asset in clinical diagnostics. To overcome quenching limitations of conventional fluorescent dyes and further improve intensity, nanoparticle-based constructs have been the subject of intense investigation, and within this realm, dye-doped silica-coated nanoparticles have garnered significant attention. Despite their growing popularity in research, fluorescent silica nanoparticles suffer from a significant flaw. The degradation of these nanoparticles in biological media by hydrolytic dissolution is underreported, leading to serious misinterpretations, and limiting their applicability for live cell and in vivo imaging. Here, the development of an ultra-stable, dye-embedded, silica-coated metal nanoparticle is reported, and its superior performance in long-term live cell imaging is demonstrated. While conventional dye-doped silica nanoparticles begin to degrade within an hour in aqueous media, by leveraging a modified liquid calcination process, this new construct is shown to be stable for at least 24 h. The stability of this metal-enhanced fluorescent probe in biologically relevant temperatures and media, and its demonstrated utility for cell imaging, paves the way for its future adoption in biomedical research.

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Santra, Swadeshmukul, Debamitra Dutta, Glenn A. Walter i Brij M. Moudgil. "Fluorescent Nanoparticle Probes for Cancer Imaging". Technology in Cancer Research & Treatment 4, nr 6 (grudzień 2005): 593–602. http://dx.doi.org/10.1177/153303460500400603.

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Optical imaging technique has strong potential for sensitive cancer diagnosis, particularly at the early stage of cancer development. This is a sensitive, non-invasive, non-ionizing (clinically safe) and relatively inexpensive technique. Cancer imaging with optical technique however greatly relies upon the use of sensitive and stable optical probes. Unlike the traditional organic fluorescent probes, fluorescent nanoparticle probes such as dye-doped nanoparticles and quantum dots (Qdots) are bright and photostable. Fluorescent nanoparticle probes are shown to be very effective for sensitive cancer imaging with greater success in the cellular level. However, cancer imaging in an in vivo setup has been recently realized. There are several challenges in developing fluorescent nanoparticle probes for in vivo cancer imaging applications. In this review, we will discuss various aspects of nanoparticle design, synthesis, surface functionalization for bioconjugation and cancer cell targeting. A brief overview of in vivo cancer imaging with Qdots will also be presented.

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Qin, Dilan, Xiaoxiao He, Kemin Wang, Xiaojun Julia Zhao, Weihong Tan i Jiyun Chen. "Fluorescent Nanoparticle-Based Indirect Immunofluorescence Microscopy for Detection ofMycobacterium tuberculosis". Journal of Biomedicine and Biotechnology 2007 (2007): 1–9. http://dx.doi.org/10.1155/2007/89364.

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A method of fluorescent nanoparticle-based indirect immunofluorescence microscopy (FNP-IIFM) was developed for the rapid detection ofMycobacterium tuberculosis. An anti-Mycobacterium tuberculosisantibody was used as primary antibody to recognizeMycobacterium tuberculosis, and then an antibody binding protein (Protein A) labeled with Tris(2,2-bipyridyl)dichlororuthenium(II) hexahydrate (RuBpy)-doped silica nanoparticles was used to generate fluorescent signal for microscopic examination. Prior to the detection, Protein A was immobilized on RuBpy-doped silica nanoparticles with a coverage of∼5.1×102molecules/nanoparticle. With this method,Mycobacterium tuberculosisin bacterial mixture as well as in spiked sputum was detected. The use of the fluorescent nanoparticles reveals amplified signal intensity and higher photostability than the direct use of conventional fluorescent dye as label. Our preliminary studies have demonstrated the potential application of the FNP-IIFM method for rapid detection ofMycobacterium tuberculosisin clinical samples.

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Ali, Haydar, Santu Ghosh i Nikhil R. Jana. "Biomolecule-derived Fluorescent Carbon Nanoparticle as Bioimaging Probe". MRS Advances 3, nr 15-16 (2018): 779–88. http://dx.doi.org/10.1557/adv.2018.80.

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ABSTRACTNanomaterials have broad application potential in biomedical and environmental science. Engineered nanomaterials are required to explore such potential. Among them carbon-based fluorescent nanoparticles offer promising alternative of conventionally used semiconductor nanocrystals, as they do not have heavy metals and associated toxicity issues. We are developing synthetic methods for high quality fluorescent carbon nanoparticle, suitable for biological staining and diagnostics. Here we focus on synthesis of fluorescent carbon nanoparticle from biomolecules, exploiting the conventionally used nucleation-growth conditions for synthesis of high quality nanocrystals such as quantum dot and metal oxides. We have shown that high quality fluorescent carbon nanoparticle can be synthesized from folic acid, riboflavin and lactose and they can be used as non-toxic bio-imaging probe.

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He, Ying. "Application of Biomimetic Nanomaterials in Biological Detection and the Intelligent Recognition Method of Nanoparticle Images". Journal of Nanoelectronics and Optoelectronics 16, nr 1 (1.01.2021): 23–30. http://dx.doi.org/10.1166/jno.2021.2904.

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New nanomaterials (metal nanoclusters, graphene, etc.) are favored by researchers due to their unique properties and are widely used in biomedical detection. The excellent fluorescence characteristics of gold nanoclusters are utilized to develop a fast and highly sensitive bionic nanomaterial with non-label and dual functions, which can detect silver ions and mercury ions and study the particularity of TEM nanoparticle images. The particle segmentation of TEM nanoparticle images is studied to compare the traditional watershed algorithm and watershed transformation algorithm. The experiment results show that silver ions can enhance the fluorescence of gold nanoclusters to form gold-silver nanoclusters with strong yellow fluorescence, and mercury ions can quickly weaken the fluorescence of gold-silver nanoclusters. Based on the biomimetic nanomaterials, a dual-function fluorescent probe is designed to detect silver ions and mercury ions in lake with detection accuracy of 8 nM and 33 nM respectively; the sensing excitation of the fluorescent probe is further analyzed. Because the metal-enhanced fluorescence (MEF) effect enables the silver element and Au nanoparticles to form fluorescence-enhancing effect, the high metalphilic interaction between mercury ions and silver ions quenches the fluorescence effect of gold nanocluster; the rapid watershed transformation/region fusion method can achieve better particle image segmentation combined with the image segmentation algorithms of different TEM nanoparticles, which can be better applied to the characterization analysis of the preparation of gold nanomaterials.

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Hendrick, Erin, Margaret Frey, Erik Herz i Ulrich Wiesner. "Cellulose Acetate Fibers with Fluorescing Nanoparticles for Anti-counterfeiting and pH-sensing Applications". Journal of Engineered Fibers and Fabrics 5, nr 1 (marzec 2010): 155892501000500. http://dx.doi.org/10.1177/155892501000500103.

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Fluorescent silica nanoparticles, Cornell dots (C dots), were incorporated into electrospun cellulose acetate (CA) fibers. Two types of C dots were used in this study. The first type was comprised of a fluorescent dye-containing silica core surrounded by a silica shell. These nanoparticles fluoresce at 572 nm when exposed to 541 nm light. Increasing C dot loading in the spinning dope above 10% w/w did not result in an increase in C dot content within the final fibers. Scanning electron microscopy indicated that the nanoparticle incorporation had very little effect on the fiber morphology. The mechanical properties of the electrospun fabrics were not negatively affected by C dot addition, even though final loading constituted nearly one-third of the weight of the fibers. A second type of C dots, with both a fluorescent core and a pH-sensitive shell, were also incorporated in CA fibers. These C dots fluoresce at both 572 nm as described above, and at 518 nm, when exposed to 488 nm light. Fluorescence intensity at 541 nm increased with increasing pH. For both nanoparticle-incorporated fabrics, the resulting fibers are white under ambient lighting, and fluoresce at their given wavelengths of light.

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Wu, Hsing-Ju, i Cheng-Chung Chang. "Fabrication of Double Emission Enhancement Fluorescent Nanoparticles with Combined PET and AIEE Effects". Molecules 25, nr 23 (4.12.2020): 5732. http://dx.doi.org/10.3390/molecules25235732.

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The major challenge in the fabrication of fluorescent silica nanoparticles (FSNs) based on dye-doped silica nanoparticles (DDSNs) is aggregation-caused fluorescence quenching. Here, we constructed an FSN based on a double emission enhancement (DEE) platform. A thio-reactive fluorescence turn-on molecule, N-butyl-4-(4-maleimidostyryl)-1,8-naphthalimide (CS), was bound to a silane coupling agent, (3-mercaptopropyl)-trimethoxysilane (MPTMS), and the product N-butyl-4-(3-(trimethoxysilyl-propylthio)styryl)-1,8-naphthalimide (CSP) was further used to fabricate a core–shell nanoparticle through the Stöber method. We concluded that the turn-on emission by CSP originated from the photoinduced electron transfer (PET) between the maleimide moiety and the CSP core scaffold, and the second emission enhancement was attributed to the aggregation-induced emission enhancement (AIEE) in CSP when encapsulated inside a core–shell nanoparticle. Thus, FSNs could be obtained through DEE based on a combination of PET and AIEE effects. Systematic investigations verified that the resulting FSNs showed the traditional solvent-independent and photostable optical properties. The results implied that the novel FSNs are suitable as biomarkers in living cells and function as fluorescent visualizing agents for intracellular imaging and drug carriers.

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Wang, Guifang, Jing Wang, Linlin Zhao, Qiang Zhang i Yan Lu. "Facile Fabrication of Fluorescent Inorganic Nanoparticles with Diverse Shapes for Cell Imaging". Nanomaterials 9, nr 2 (26.01.2019): 154. http://dx.doi.org/10.3390/nano9020154.

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In the present work, we describe a facile and general method of fabricating fluorescent inorganic nanoparticles with diverse shapes for cell imaging application. The hematite (α-Fe2O3) nanoparticles (HNPs) with three different shapes (i.e., spindle shape, ellipsoidal shape and quasi-spherical shape) were first prepared as model systems in consideration of good biocompatibility and the controllable morphology of α-Fe2O3. Three fluorescent HNPs with different shapes were readily achieved via one-pot sol-gel reaction of AIE luminogen-functionalized siloxane (AIEgen-Si(OCH3)3) and TEOS in the presence of PVP-stabilized HNPs. Due to the fluorescence originating from the thin AIEgens-contained SiO2 shell around the HNPs, their photoluminescent intensities can be tuned by changing the concentrations of TEOS and AIEgen-Si(OCH3)3 in feed prior to the sol-gel reaction. When the as-prepared fluorescent products were dispersed in water, they gave intense green light emission upon excitation at 360 nm with relatively high fluorescence quantum yield. Further, fluorescent HNPs exhibited low cytotoxicity and excellent photostability and, thus, were used as optical probes to preliminarily explore the effect of nanoparticle shapes on their cellular uptake behaviors. This work should open a facile way to prepare various fluorescent inorganic nanoparticles with specific morphology for various biological applications.

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Nifontova, Galina, Victor Krivenkov, Mariya Zvaigzne, Anton Efimov, Evgeny Korostylev, Sergei Zarubin, Alexander Karaulov, Igor Nabiev i Alyona Sukhanova. "Nanoparticle-Doped Hybrid Polyelectrolyte Microcapsules with Controlled Photoluminescence for Potential Bioimaging Applications". Polymers 13, nr 23 (24.11.2021): 4076. http://dx.doi.org/10.3390/polym13234076.

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Fluorescent imaging is widely used in the diagnosis and tracking of the distribution, interaction, and transformation processes at molecular, cellular, and tissue levels. To be detectable, delivery systems should exhibit a strong and bright fluorescence. Quantum dots (QDs) are highly photostable fluorescent semiconductor nanocrystals with wide absorption spectra and narrow, size-tunable emission spectra, which make them suitable fluorescent nanolabels to be embedded into microparticles used as bioimaging and theranostic agents. The layer-by-layer deposition approach allows the entrapping of QDs, resulting in bright fluorescent microcapsules with tunable surface charge, size, rigidity, and functional properties. Here, we report on the engineering and validation of the structural and photoluminescent characteristics of nanoparticle-doped hybrid microcapsules assembled by the deposition of alternating oppositely charged polyelectrolytes, water-soluble PEGylated core/shell QDs with a cadmium selenide core and a zinc sulfide shell (CdSe/ZnS), and carboxylated magnetic nanoparticles (MNPs) onto calcium carbonate microtemplates. The results demonstrate the efficiency of the layer-by-layer approach to designing QD-, MNP-doped microcapsules with controlled photoluminescence properties, and pave the way for the further development of next-generation bioimaging agents based on hybrid materials for continuous fluorescence imaging.

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Álamo, Patricia, Victor Pallarès, María Virtudes Céspedes, Aïda Falgàs, Julieta M. Sanchez, Naroa Serna, Laura Sánchez-García i in. "Fluorescent Dye Labeling Changes the Biodistribution of Tumor-Targeted Nanoparticles". Pharmaceutics 12, nr 11 (22.10.2020): 1004. http://dx.doi.org/10.3390/pharmaceutics12111004.

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Fluorescent dye labeling is a common strategy to analyze the fate of administered nanoparticles in living organisms. However, to which extent the labeling processes can alter the original nanoparticle biodistribution has been so far neglected. In this work, two widely used fluorescent dye molecules, namely, ATTO488 (ATTO) and Sulfo-Cy5 (S-Cy5), have been covalently attached to a well-characterized CXCR4-targeted self-assembling protein nanoparticle (known as T22-GFP-H6). The biodistribution of labeled T22-GFP-H6-ATTO and T22-GFP-H6-S-Cy5 nanoparticles has been then compared to that of the non-labeled nanoparticle in different CXCR4+ tumor mouse models. We observed that while parental T22-GFP-H6 nanoparticles accumulated mostly and specifically in CXCR4+ tumor cells, labeled T22-GFP-H6-ATTO and T22-GFP-H6-S-Cy5 nanoparticles showed a dramatic change in the biodistribution pattern, accumulating in non-target organs such as liver or kidney while reducing tumor targeting capacity. Therefore, the use of such labeling molecules should be avoided in target and non-target tissue uptake studies during the design and development of targeted nanoscale drug delivery systems, since their effect over the fate of the nanomaterial can lead to considerable miss-interpretations of the actual nanoparticle biodistribution.

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Ouyang, Leixin, Rubia Shaik, Ruiting Xu, Ge Zhang i Jiang Zhe. "Mapping Surface Charge Distribution of Single-Cell via Charged Nanoparticle". Cells 10, nr 6 (16.06.2021): 1519. http://dx.doi.org/10.3390/cells10061519.

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Many bio-functions of cells can be regulated by their surface charge characteristics. Mapping surface charge density in a single cell’s surface is vital to advance the understanding of cell behaviors. This article demonstrates a method of cell surface charge mapping via electrostatic cell–nanoparticle (NP) interactions. Fluorescent nanoparticles (NPs) were used as the marker to investigate single cells’ surface charge distribution. The nanoparticles with opposite charges were electrostatically bonded to the cell surface; a stack of fluorescence distribution on a cell’s surface at a series of vertical distances was imaged and analyzed. By establishing a relationship between fluorescent light intensity and number of nanoparticles, cells’ surface charge distribution was quantified from the fluorescence distribution. Two types of cells, human umbilical vein endothelial cells (HUVECs) and HeLa cells, were tested. From the measured surface charge density of a group of single cells, the average zeta potentials of the two types of cells were obtained, which are in good agreement with the standard electrophoretic light scattering measurement. This method can be used for rapid surface charge mapping of single particles or cells, and can advance cell-surface-charge characterization applications in many biomedical fields.

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Pack, Chan-Gi, Bjorn Paulson, Yeonhee Shin, Min Kyo Jung, Jun Sung Kim i Jun Ki Kim. "Variably Sized and Multi-Colored Silica-Nanoparticles Characterized by Fluorescence Correlation Methods for Cellular Dynamics". Materials 14, nr 1 (23.12.2020): 19. http://dx.doi.org/10.3390/ma14010019.

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Controlling the uptake of nanoparticles into cells so as to balance therapeutic effects with toxicity is an essential unsolved problem in the development of nanomedicine technologies. From this point of view, it is useful to use standard nanoparticles to quantitatively evaluate the physical properties of the nanoparticles in solution and in cells, and to analyze the intracellular dynamic motion and distribution of these nanoparticles at a single-particle level. In this study, standard nanoparticles are developed based on a variant silica-based nanoparticle incorporating fluorescein isothiocyanate (FITC) or/and rhodamine B isothiocyanate (RITC) with a variety of accessible diameters and a matching fluorescent cobalt ferrite core-shell structure (Fe2O4/SiO2). The physical and optical properties of the nanoparticles in vitro are fully evaluated with the complementary methods of dynamic light scattering, electron microscopy, and two fluorescence correlation methods. In addition, cell uptake of dual-colored and core/shell nanoparticles via endocytosis in live HeLa cells is detected by fluorescence correlation spectroscopy and electron microscopy, indicating the suitability of the nanoparticles as standards for further studies of intracellular dynamics with multi-modal methods.

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Dehlinger, Dietrich, Benjamin Sullivan, Sadik Esener, Dalibor Hodko, Paul Swanson i Michael J. Heller. "Automated Combinatorial Process for Nanofabrication of Structures Using Bioderivatized Nanoparticles". JALA: Journal of the Association for Laboratory Automation 12, nr 5 (październik 2007): 267–76. http://dx.doi.org/10.1016/j.jala.2007.05.006.

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A fully automated electronic microarray control system (Nanochip 400 System) was used to carry out a combinatorial process to determine optimal conditions for fabricating higher order three-dimensional nanoparticle structures. Structures with up to 40 layers of bioderivatized nanoparticles were fabricated on a 400-test site CMOS microarray using the automated Nanochip 400 System. Reconfigurable electric fields produced on the surface of the CMOS microarray device actively transport, concentrate, and promote binding of 40 nm biotin- and streptavidin-derivatized nanoparticles to selected test sites on the microarray surface. The overall fabrication process including nanoparticle reagent delivery to the microarray device, electronic control of the CMOS microarray and the optical/fluorescent detection, and monitoring of nanoparticle layering are entirely controlled by the Nanochip 400 System. The automated nanoparticle layering process takes about 2 minutes per layer, with 10–20 seconds required for the electronic addressing and binding of nanoparticles, and roughly 60 seconds for washing. The addressing and building process is monitored by changes in fluorescence intensity as each nanoparticle layer is deposited. The final multilayered 3D structures are about 2 μm in thickness and 55 μm in diameter. Multilayer nanoparticle structures and control sites on the microarray were verified by SEM analysis.

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Nishida, Naoki, Edakkattuparambil S. Shibu, Hiroshi Yao, Tsugao Oonishi, Keisaku Kimura i Thalappil Pradeep. "Fluorescent Gold Nanoparticle Superlattices". Advanced Materials 20, nr 24 (16.12.2008): 4719–23. http://dx.doi.org/10.1002/adma.200800632.

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Kumar, Dhurjati Prasad. "Synthesis of gold nanoparticles and nanoclusters in a supramolecular gel and their applications in catalytic reduction of p-nitrophenol to p-aminophenol and Hg(ii) sensing". RSC Adv. 4, nr 85 (2014): 45449–57. http://dx.doi.org/10.1039/c4ra07532c.

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Seven gelator molecules giving supramolecular gels produced Au-nanoparticles and fluorescent, small Au-nanoclusters. Such Au-nanoparticle containing gels catalyzed the reduction of p-nitrophenol to p-aminophenol without NaBH₄. The fluorescent Au-nanoclusters acted as a Hg(ii) sensor.

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Tsirikis, Peter, Kirsty Wilson, Sue Xiang, Wei Wei, Guanghui Ma, Cordelia Selomulya i Magdalena Plebanski. "Immunogenicity and biodistribution of nanoparticles in vivo". Journal of Immunology 196, nr 1_Supplement (1.05.2016): 75.28. http://dx.doi.org/10.4049/jimmunol.196.supp.75.28.

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Abstract Nanoparticles have been widely used in vaccine design as both adjuvants and antigen delivery vehicles. In a seminal study, 40–50 nm nanoparticles with conjugated antigen were shown to induce high antibody titers and IFN-γ production in mice but with no added inflammatory stimuli. Subsequent research has shown that similar levels of immunogenicity can be achieved via the co-injection of naked 40–50 nm nanoparticles adjuvants and larger 500 nm nanoparticles with conjugated antigen. Furthermore, recent works indicate that particle shape can also influence the immune response. As such, we investigate the influence of surface morphology using 40–50 nm smooth and rough surfaced nanoparticle adjuvants and report their differential immunogenicity via ELISA, ELISpot and flow cytometry. Further, we determine the biodistribution of fluorescent 40–50 nm nanoparticle adjuvants with smooth and rough surfaces and larger 500 nm nanoparticles. Nanoparticle size is shown to be a discriminating factor in lymph node drainage, using a Carestream FX PRO in vivo imaging system and fluorescence microscopy of lymph nodes sectioned ex vivo. To elucidate the safety profile of this vaccine construct, we also investigate the biodistribution of nanoparticles within the major organs. The outcomes from this study provide key design criteria in the development of novel nanoparticle immunotherapeutics for the treatment of disease.

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Kircher, Moritz F., Lee Josephson i Ralph Weissleder. "Ratio Imaging of Enzyme Activity Using Dual Wavelength Optical Reporters". Molecular Imaging 1, nr 2 (1.04.2002): 153535002002011. http://dx.doi.org/10.1162/15353500200201124.

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The design of near-infrared fluorescent (NIRF) probes that are activated by specific proteases has, for the first time, allowed enzyme activity to be imaged in vivo. In the current study, we report on a method of imaging enzyme activity using two fluorescent probes that, together, provide improved quantitation of enzymatic activity. The method employs two chemically similar probes that differ in their degradability by cathepsin B. One probe consists of the NIRF dye Cy5.5 attached to a particulate carrier, a crosslinked iron oxide nanoparticle (CLIO), through cathepsin B cleavable l-arginyl peptides. A second probe consists of Cy3.5 attached to a CLIO through proteolytically resistant d-arginyl peptides. Using mixtures of the two probes, we have shown that the ratio of Cy5.5 to Cy3.5 fluorescence can be used to determine levels of cathepsin B in the environment of nanoparticles with macrophages in suspension. After intravenous injection, tissue fluorescence from the nondegradable Cy3.5–d-arginyl probe reflected nanoparticle accumulation, while fluorescence of the Cy5.5–l-arginyl probe was dependent on both accumulation and activation by cathepsin B. Dual wavelength ratio imaging can be used for the quantitative imaging of a variety of enzymes in clinically important settings, while the magnetic properties of the probes allow their detection by MR imaging.

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Han, Hadas, Sara Eyal, Emma Portnoy, Aniv Mann, Miriam Shmuel, Mony Benifla, Dana Ekstein i Boris Polyak. "Monocytes as Carriers of Magnetic Nanoparticles for Tracking Inflammation in the Epileptic Rat Brain". Current Drug Delivery 16, nr 7 (3.10.2019): 637–44. http://dx.doi.org/10.2174/1567201816666190619122456.

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Background: Inflammation is a hallmark of epileptogenic brain tissue. Previously, we have shown that inflammation in epilepsy can be delineated using systemically-injected fluorescent and magnetite- laden nanoparticles. Suggested mechanisms included distribution of free nanoparticles across a compromised blood-brain barrier or their transfer by monocytes that infiltrate the epileptic brain. Objective: In the current study, we evaluated monocytes as vehicles that deliver nanoparticles into the epileptic brain. We also assessed the effect of epilepsy on the systemic distribution of nanoparticleloaded monocytes. Methods: The in vitro uptake of 300-nm nanoparticles labeled with magnetite and BODIPY (for optical imaging) was evaluated using rat monocytes and fluorescence detection. For in vivo studies we used the rat lithium-pilocarpine model of temporal lobe epilepsy. In vivo nanoparticle distribution was evaluated using immunohistochemistry. Results: 89% of nanoparticle loading into rat monocytes was accomplished within 8 hours, enabling overnight nanoparticle loading ex vivo. The dose-normalized distribution of nanoparticle-loaded monocytes into the hippocampal CA1 and dentate gyrus of rats with spontaneous seizures was 176-fold and 380-fold higher compared to the free nanoparticles (p<0.05). Seizures were associated with greater nanoparticle accumulation within the liver and the spleen (p<0.05). Conclusion: Nanoparticle-loaded monocytes are attracted to epileptogenic brain tissue and may be used for labeling or targeting it, while significantly reducing the systemic dose of potentially toxic compounds. The effect of seizures on monocyte biodistribution should be further explored to better understand the systemic effects of epilepsy.

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Bansal, Akshaya, Muthu Kumara Gnanasammandhan i Yong Zhang. "Multi-Functional Fluorescent Upconversion Nanocrystals for Simultaneous Imaging and Delivery of Peptide Toxins". Key Engineering Materials 605 (kwiecień 2014): 364–67. http://dx.doi.org/10.4028/www.scientific.net/kem.605.364.

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The major hurdles faced by therapeutic biomolecules to reach clinical use are non-specificity, unnecessary side effects, sensitivity to environmental factors and poor cellular uptake. Several nanoparticle systems have been developed to overcome these issues but there are still some bottlenecks such as nanoparticle toxicity, bioavailability and inability to track the biomolecules post-delivery. Here we report the use of multi-functional lanthanide-based fluorescent upconversion nanoparticles as a safe delivery vector for peptides as well as for fluorescent tracking of delivery or for in-vitro/in-vivo imaging. The UCNs are excited by a NIR light source and emit in the Visible region. Since NIR light is used for excitation, the nanoparticles could be used for deep tissue imaging. Highly monodisperse uniformly sized, sub-100 nm, biocompatible upconversion nanoparticles were synthesized with a mesoporous silica coating. Amanitin, a peptide toxin was used as a model peptide and was loaded onto the mesoporous silica coated UCNs. The peptide loaded UCNs were delivered to B16F0 melanoma cells and significant cell death was achieved within 24 hours. The unloaded UCNs however had negligible toxicity. The UCNs were also used for imaging the cells with very good signal-to-noise ratio and almost nil background autofluorescence. The fluorescence from the UCNs was non-blinking, highly stable and could be used for long-term tracking.

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Forgách, László, Nikolett Hegedűs, Ildikó Horváth, Bálint Kiss, Noémi Kovács, Zoltán Varga, Géza Jakab i in. "Fluorescent, Prussian Blue-Based Biocompatible Nanoparticle System for Multimodal Imaging Contrast". Nanomaterials 10, nr 9 (31.08.2020): 1732. http://dx.doi.org/10.3390/nano10091732.

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(1) Background. The main goal of this work was to develop a fluorescent dye-labelling technique for our previously described nanosized platform, citrate-coated Prussian blue (PB) nanoparticles (PBNPs). In addition, characteristics and stability of the PB nanoparticles labelled with fluorescent dyes were determined. (2) Methods. We adsorbed the fluorescent dyes Eosin Y and Rhodamine B and methylene blue (MB) to PB-nanoparticle systems. The physicochemical properties of these fluorescent dye-labeled PBNPs (iron(II);iron(III);octadecacyanide) were determined using atomic force microscopy, dynamic light scattering, zeta potential measurements, scanning- and transmission electron microscopy, X-ray diffraction, and Fourier-transformation infrared spectroscopy. A methylene-blue (MB) labelled, polyethylene-glycol stabilized PBNP platform was selected for further assessment of in vivo distribution and fluorescent imaging after intravenous administration in mice. (3) Results. The MB-labelled particles emitted a strong fluorescent signal at 662 nm. We found that the fluorescent light emission and steric stabilization made this PBNP-MB particle platform applicable for in vivo optical imaging. (4) Conclusion. We successfully produced a fluorescent and stable, Prussian blue-based nanosystem. The particles can be used as a platform for imaging contrast enhancement. In vivo stability and biodistribution studies revealed new aspects of the use of PBNPs.

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Kaniuk, M. I. "MULTIFUNCTIONAL NANOSYSTEMS BASED ON TWO FLUORESCENT DYES, DOXORUBICIN AND CURCUMIN". Biotechnologia Acta 15, nr 6 (30.12.2022): 5–25. http://dx.doi.org/10.15407/biotech15.06.005.

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The aim of the work was to review the literature data regarding the prospects for the creation and use of multifunctional fluorescent two-dye nanosystems, which enable investigating the distribution of fluorescent components with significant acceleration of the study and introduction of nanomedicines into practice. Special attention is paid to the use of two substances with hydrophobic and hydrophilic properties in one nanoparticle (NP), capable of penetrating a living cell. The method of fluorescence confocal microscopy enables observation of the nanoscale dynamics of distribution and stability of drugs over time. The concomitant use of doxorubicin (DOX) and curcumin (CUR) in single nanoparticle causes synergism in the action of medical drugs, and their own fluorescence makes it possible to use them as multifunctional fluorescent nanosystems. Results. Data from the literature indicate that the use of two or more fluorescent dyes provide an advantage over other, more expensive methods when studying the penetration and distribution of NPs in living samples. The use of nanocarriers is an effective way to significantly increase the bioavailability of those drugs, which are poorly soluble in water. A promising direction of nanomedicine is the creation of complex bio-compatible multifunctional nanomaterials based on several active drugs, with the simultaneous use of their enhancers and the strategy of active targeting. Such recent structures enable targeted and controlled penetration of medicinal compounds into the sites of localization of pathological processes, reducing the toxicity of drugs to normal cells. Conclusions. The use of the fluorescence microscopy method, as exemplified by the two dyes, DOX and CUR, enables to trace the stages of interaction of loaded DOX and CUR nanoparticles with cultured cells, and their release from NPs to determine their amount and localization in organelles cells.

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Albarki, Mohammed A., i Maureen D. Donovan. "Uptake of Cationic PAMAM-PLGA Nanoparticles by the Nasal Mucosa". Scientia Pharmaceutica 90, nr 4 (25.11.2022): 72. http://dx.doi.org/10.3390/scipharm90040072.

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Nanoparticles provide promising advantages in advanced delivery systems for enhanced drug delivery and targeting. The use of a biodegradable polymer such as PLGA (poly lactic-co-glycolic acid) promotes improved nanoparticle safety and, to some extent, provides the ability to modify nanoparticle surface properties. This study compared the effect of altering the surface charge on the translocation of PLGA nanoparticles across excised nasal mucosal tissues. Nanoparticles (average diameter of 60–100 nm) loaded with Nile Red (lipophilic fluorescent dye) were fabricated using a nanoprecipitation method. The effects of nanoparticle surface charge were investigated by comparing the transfer of untreated nanoparticles (negatively charged) and positively charged PLGA nanoparticles, which were modified using PAMAM dendrimer (polyamidoamine, 5th generation). All nanoparticles were able to be transferred in measurable quantities into both nasal respiratory and olfactory mucosae within 30 min. The total nanoparticle uptake was less than 5% of the nanoparticle mass exposed to the tissue surface. The cationic nanoparticles showed a significantly lower transfer into the mucosal tissues where the amount of nanoparticles transferred was 1.8–4-fold lower compared to the untreated negatively charged nanoparticles. The modification of the nanoparticle surface charge can alter the nanoparticle interaction with the nasal epithelial surface, which can result in decreasing the nanoparticle transfer into the nasal mucosa.

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Hayashi, Terutake, Toshiki Seri i Syuhei Kurokawa. "A Novel Particle Sizing Method for Nano Abrasives in CMP Slurry by Using Fluorescent Nano Probe". International Journal of Automation Technology 11, nr 5 (30.08.2017): 754–60. http://dx.doi.org/10.20965/ijat.2017.p0754.

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In this study, a novel particle sizing method is proposed based on Brownian diffusion analysis for abrasive particles using fluorescent probing. A fluorescent probe is used to measure the average dynamic viscosity of the nanoparticle dispersion in a solvent. By measuring both the average dynamic viscosity and the size of the nanoscale abrasive particles simultaneously, the uncertainty of the particle sizing is considered to be improved based on the viscosity compensation for the Brownian diffusion of nanoparticles. In this research, the authors investigate the difference between the nanoviscosity and the shear viscosity of the solvent to verify the efficacy in using viscosity compensation for nanoparticle sizing.

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Bollhorst, T., S. Jakob, J. Köser, M. Maas i K. Rezwan. "Chitosan supraparticles with fluorescent silica nanoparticle shells and nanodiamond-loaded cores". Journal of Materials Chemistry B 5, nr 8 (2017): 1664–72. http://dx.doi.org/10.1039/c6tb03069f.

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Supraparticles with a biopolymer chitosan core and templated with (ultra)small nanoparticles are reported. Nanoparticle density on the template surface could be controlled and the template core could be loaded with nanodiamonds.

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Yang, Tao, Chuying Feng, Peng Zhao, Yusen Wu, Yun Ding, Guiyou Wang i Aiguo Hu. "Fluorescent electronic tongue supported with water-borne polyurethane for the discrimination of nitroaromatics in aqueous solution". Journal of Materials Chemistry C 8, nr 7 (2020): 2500–2506. http://dx.doi.org/10.1039/c9tc06759k.

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Fluorescent electronic tongues are designed for the quick discrimination of nitroaromatics in aqueous solution through fluorescence quenching of soluble conjugated polymeric nanoparticle (SCPN) arrays supported with water-borne polyurethane.

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Tavernaro, Isabella, Christian Cavelius, Henrike Peuschel i Annette Kraegeloh. "Bright fluorescent silica-nanoparticle probes for high-resolution STED and confocal microscopy". Beilstein Journal of Nanotechnology 8 (21.06.2017): 1283–96. http://dx.doi.org/10.3762/bjnano.8.130.

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In recent years, fluorescent nanomaterials have gained high relevance in biological applications as probes for various fluorescence-based spectroscopy and imaging techniques. Among these materials, dye-doped silica nanoparticles have demonstrated a high potential to overcome the limitations presented by conventional organic dyes such as high photobleaching, low stability and limited fluorescence intensity. In the present work we describe an effective approach for the preparation of fluorescent silica nanoparticles in the size range between 15 and 80 nm based on L-arginine-controlled hydrolysis of tetraethoxysilane in a biphasic cyclohexane–water system. Commercially available far-red fluorescent dyes (Atto647N, Abberior STAR 635, Dy-647, Dy-648 and Dy-649) were embedded covalently into the particle matrix, which was achieved by aminosilane coupling. The physical particle attributes (particle size, dispersion, degree of agglomeration and stability) and the fluorescence properties of the obtained particles were compared to particles from commonly known synthesis methods. As a result, the spectroscopic characteristics of the presented monodisperse dye-doped silica nanoparticles were similar to those of the free uncoupled dyes, but indicate a much higher photostability and brightness. As revealed by dynamic light scattering and ζ-potential measurements, all particle suspensions were stable in water and cell culture medium. In addition, uptake studies on A549 cells were performed, using confocal and stimulated emission depletion (STED) microscopy. Our approach allows for a step-by-step formation of dye-doped silica nanoparticles in the form of dye-incorporated spheres, which can be used as versatile fluorescent probes in confocal and STED imaging.

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Gandla, Kumaraswamy, K. Praveen Kumar, P. Rajasulochana, Manoj Shrawan Charde, Ritesh Rana, Laliteshwar Pratap Singh, M. Akiful Haque i in. "Fluorescent-Nanoparticle-Impregnated Nanocomposite Polymeric Gels for Biosensing and Drug Delivery Applications". Gels 9, nr 8 (18.08.2023): 669. http://dx.doi.org/10.3390/gels9080669.

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Nanocomposite polymeric gels infused with fluorescent nanoparticles have surfaced as a propitious category of substances for biomedical purposes owing to their exceptional characteristics. The aforementioned materials possess a blend of desirable characteristics, including biocompatibility, biodegradability, drug encapsulation, controlled release capabilities, and optical properties that are conducive to imaging and tracking. This paper presents a comprehensive analysis of the synthesis and characterization of fluorescent-nanoparticle-impregnated nanocomposite polymeric gels, as well as their biomedical applications, such as drug delivery, imaging, and tissue engineering. In this discourse, we deliberate upon the merits and obstacles linked to these substances, encompassing biocompatibility, drug encapsulation, optical characteristics, and scalability. The present study aims to provide an overall evaluation of the potential of fluorescent-nanoparticle-impregnated nanocomposite polymeric gels for biomedical applications. Additionally, emerging trends and future directions for research in this area are highlighted.

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Zhang, Wenchi, Xin Li, Xuechao Xu, Yanfang He, Fengxian Qiu, Jianming Pan i Xiangheng Niu. "Pd nanoparticle-decorated graphitic C3N4 nanosheets with bifunctional peroxidase mimicking and ON–OFF fluorescence enable naked-eye and fluorescent dual-readout sensing of glucose". Journal of Materials Chemistry B 7, nr 2 (2019): 233–39. http://dx.doi.org/10.1039/c8tb02110d.

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Anăstăsoaie, Veronica, Roxana Tomescu, Cristian Kusko, Iuliana Mihalache, Adrian Dinescu, Catalin Parvulescu, Gabriel Craciun, Stefan Caramizoiu i Dana Cristea. "Influence of Random Plasmonic Metasurfaces on Fluorescence Enhancement". Materials 15, nr 4 (15.02.2022): 1429. http://dx.doi.org/10.3390/ma15041429.

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One of the strategies employed to increase the sensitivity of the fluorescence-based biosensors is to deposit chromophores on plasmonic metasurfaces which are periodic arrays of resonating nano-antennas that allow the control of the electromagnetic field leading to fluorescence enhancement. While artificially engineered metasurfaces realized by micro/nano-fabrication techniques lead to a precise tailoring of the excitation field and resonant cavity properties, the technological overhead, small areas, and high manufacturing cost renders them unsuitable for mass production. A method to circumvent these challenges is to use random distribution of metallic nanoparticles sustaining plasmonic resonances, which present the properties required to significantly enhance the fluorescence. We investigate metasurfaces composed of random aggregates of metal nanoparticles deposited on a silicon and glass substrates. The finite difference time domain simulations of the interaction of the incident electromagnetic wave with the structures reveals a significant enhancement of the excitation field, which is due to the resonant plasmonic modes sustained by the nanoparticles aggregates. We experimentally investigated the role of these structures in the fluorescent behaviour of Rhodamine 6G dispersed in polymethylmethacrylate finding an enhancement that is 423-fold. This suggests that nanoparticle aggregates have the potential to constitute a suitable platform for low-cost, mass-produced fluorescent biosensors.

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Scull, Christopher M., Ruben Kuruvilla, Thomas H. Fischer i Timothy C. Nichols. "Gene Transfer to Macrophages with Nanoparticle-Loaded Platelets." Blood 106, nr 11 (16.11.2005): 3043. http://dx.doi.org/10.1182/blood.v106.11.3043.3043.

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Abstract Hemorrhagic fever, traumatic brain injury, and inflammatory bowel syndrome are among a wide range of pathologies involving inflammation that results in bleeding. The vascular injury that occurs in these conditions is closely associated with macrophage activation. An inherent function of macrophages is to phagocytose platelets that have adhered to sites of vascular injury, and thus platelets are an ideal vehicle for site-specific delivery of anti-inflammatory genes to macrophages at wound sites. Here we report the preparation of reporter gene nanoparticle-platelet conjugates and gene transfer to macrophages. Plasmid-containing nanoparticles were prepared by condensing cDNA for β-galactosidase, green fluorescent protein, or luciferase with polyethyleneimine. Scanning electron microscopic analysis showed that this anion/cation agglomeration reaction yields spherical particles with diameters of 100 to 300 nm. Plasmid-containing nanoparticles were then incubated with platelets that were isolated from human blood by differential centrifugation. Flow cytometric and transmission electron microscopic analysis demonstrated that the nanoparticles associated with the surface-connected canalicular system with most platelets containing one or more particles. The ability of the nanoparticle-loaded platelets to transfer the reporter genes to macrophages was tested in tissue culture using monocyte-derived macrophages incubated with the nanoparticle-loaded platelets. Subsequent fluorescent microscopic, luminescent and histological analysis demonstrated that the macrophages readily phagocytosed the nanoparticle-loaded platelets and expressed the reporter genes. This result provides the basis for studies to deliver anti-inflammatory genes to macrophages in animal model systems.

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Eisner, Christoph, Hooisweng Ow, Tianxin Yang, Zhanjun Jia, Emilios Dimitriadis, Lingli Li, Kenneth Wang i in. "Measurement of plasma volume using fluorescent silica-based nanoparticles". Journal of Applied Physiology 112, nr 4 (15.02.2012): 681–87. http://dx.doi.org/10.1152/japplphysiol.01068.2011.

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Plasma volume (PV) is an important determinant of cardiovascular function and organ perfusion, and it is the target of infusion and diuretic therapies in daily clinical practice. Despite its fundamental importance PV is not commonly measured because available methods of tracer dilution are reliant on dye substances that suffer from numerous drawbacks including binding plasma proteins, spectral changes, and clearance kinetics that complicate analysis and interpretation. To address these issues, we have tested the utility of fluorescent nanoparticles comprised of a dye-rich silica core and polyethylene glycol-coated shell. Photophysical and visual analysis showed discrete size-gradated nanoparticle populations could be synthesized within a distribution tolerance of ±4 nm, which were optically unaffected in the presence of plasma/albumin. In normal mice, the cutoff for renal filtration of nanoparticles from blood into urine was ≤11 nm. A linear relationship between body weight and PV was readily determined in mice administered far red fluorescent nanoparticles sized either 20 or 30 nm. PV measurements using nanoparticles were correlated to values obtained with Evans blue dye. Induced expansion or contraction of PV was demonstrated with albumin or furosemide administration, respectively, in mice. Longitudinal experiments >30 min required matched untreated control mice to correct for nanoparticle loss (≈30%) putatively to the reticuloendothelial/phagocyte system. Collectively, the findings support a nanotechnology-based solution to methodological problems in measure of PV, notably in clinical settings where information on hemodynamic changes may improve treatment of injury and disease.

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Cakir-Aktas, Canan, Sefik Evren Erdener, Büşra Teke, Sibel Bozdag Pehlivan, Naciye Dilara Zeybek, Aslihan Taskiran-Sag, Zeynep Kaya, Turgay Dalkara i Melike Mut. "Confocal reflectance microscopy for metal and lipid nanoparticle visualization in the brain". Nanomedicine 17, nr 7 (marzec 2022): 447–60. http://dx.doi.org/10.2217/nnm-2021-0350.

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Aim: A requirement for nanoparticle (NP) research is visualization of particles within cells and tissues. Limitations of electron microscopy and low yields of NP fluorescent tagging warrant the identification of alternative imaging techniques. Method: Confocal reflectance microscopy (CRM) in combination with fluorescence imaging was assessed for visualizing rhodamine B-conjugated silver and fluorescein isothiocyanate-conjugated lipid core-stearylamine NP uptake in vitro and in vivo. Results: CRM successfully identified cellular uptake and blood–brain barrier penetration of NPs owing to their distinguishing refractive indices. NP-dependent reflectance signals in vitro were dose and incubation time dependent. Finally, CRM facilitated the distinction between nonspecific fluorescence signals and NPs. Conclusion: These findings demonstrate the value of CRM for NP visualization in tissues, which can be performed with a standard confocal microscope.

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Fernández-Ponce, C., J. M. Mánuel, R. Fernández-Cisnal, E. Félix, J. Beato-López, J. P. Muñoz-Miranda, A. M. Beltrán i in. "Superficial Characteristics and Functionalization Effectiveness of Non-Toxic Glutathione-Capped Magnetic, Fluorescent, Metallic and Hybrid Nanoparticles for Biomedical Applications". Metals 11, nr 3 (26.02.2021): 383. http://dx.doi.org/10.3390/met11030383.

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An optimal design of nanoparticles suitable for biomedical applications requires proper functionalization, a key step in the synthesis of such nanoparticles, not only for subsequent crosslinking to biological targets and to avoid cytotoxicity, but also to endow these materials with colloidal stability. In this sense, a reliable characterization of the effectiveness of the functionalization process would, therefore, be crucial for subsequent bioconjugations. In this work, we have analyzed glutathione as a means to functionalize four of the most widely used nanoparticles in biomedicine, one of which is a hybrid gold-magnetic-iron-oxide nanoparticle synthetized by a simple and novel method that we propose in this article. We have analyzed the colloidal characteristics that the glutathione capping provides to the different nanoparticles and, using information on the Z-potential, we have deduced the chemical group used by glutathione to link to the nanoparticle core. We have used electron microscopy for further structural and chemical characterization of the nanoparticles. Finally, we have evaluated nanoparticle cytotoxicity, studying cell viability after incubation with different concentrations of nanoparticles, showing their suitability for biomedical applications.

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Smirnova, Tatyana D., Elens A. Zhelobitskaya, Tatyana G. Danilina i Natalya A. Simbireva. "FLUORESCENT PROPERTIES OF DOXYCYCLINE IN PRESENCE OF SILVER NANOCLUSTERS". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 64, nr 1 (8.12.2020): 34–40. http://dx.doi.org/10.6060/ivkkt.20216401.6249.

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The paper shows that in the presence of silver nanoparticles the efficiency of intramolecular energy transfer in the complex of europium with doxycycline increases. It is proved that sensitivity of determination increases and limit of detection of doxycycline decreases by the method of sensitized fluorescence. The justification of the observed effects is given. The amplification of the signal of sensitized fluorescence in the presence of silver nanoparticles (energy donor) is the result of resonant transfer of excitation energy between the nanoparticle and the antibiotic ion, which is implemented under conditions of overlapping of the local surface plasmon resonance spectrum and excitation of the doxycycline ligand located near the surface of the nanoparticle. As a result of exposure to the antibiotic external radiation source and the local field of the surface plasmon increases the efficiency of tetracycline excitation, which contributes to the effectiveness of intramolecular energy transfer in europium chelate with doxycycline, doubling the intensity and lifetime. Modification of the surface of silver nanoparticles by europium ions allows to reduce the distance between the surface of a nanoparticle and an antibiotic, to increase the intensity of the signal of sensitized fluorescence by more than 100 times. The role of the stabilizer of a non-chromophore-containing ligand, − citrateion, in the formation of the analytical signal lies in its participation in the formation of a multi-ligand Eu3+ complex on the surface of a nanoobject, which reduces the distance between the donor and the acceptor, as well as the additional removal of water molecules from the immediate environment of the complexing agent ion, suppressing the process of excitation energy dissipation. On the basis of the conducted researches the fluorimetric technique of definition of doxycycline in medicines is offered. It differs in a low limit of detection (6.0·10-9 M) and a wide range of the defined concentrations from 1.0·10-8 to 1.0·10-5 M.

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Smirnova, Tatyana D., Elens A. Zhelobitskaya, Tatyana G. Danilina i Natalya A. Simbireva. "FLUORESCENT PROPERTIES OF DOXYCYCLINE IN PRESENCE OF SILVER NANOCLUSTERS". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 64, nr 1 (8.12.2020): 34–40. http://dx.doi.org/10.6060/ivkkt.20216401.6249.

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The paper shows that in the presence of silver nanoparticles the efficiency of intramolecular energy transfer in the complex of europium with doxycycline increases. It is proved that sensitivity of determination increases and limit of detection of doxycycline decreases by the method of sensitized fluorescence. The justification of the observed effects is given. The amplification of the signal of sensitized fluorescence in the presence of silver nanoparticles (energy donor) is the result of resonant transfer of excitation energy between the nanoparticle and the antibiotic ion, which is implemented under conditions of overlapping of the local surface plasmon resonance spectrum and excitation of the doxycycline ligand located near the surface of the nanoparticle. As a result of exposure to the antibiotic external radiation source and the local field of the surface plasmon increases the efficiency of tetracycline excitation, which contributes to the effectiveness of intramolecular energy transfer in europium chelate with doxycycline, doubling the intensity and lifetime. Modification of the surface of silver nanoparticles by europium ions allows to reduce the distance between the surface of a nanoparticle and an antibiotic, to increase the intensity of the signal of sensitized fluorescence by more than 100 times. The role of the stabilizer of a non-chromophore-containing ligand, − citrateion, in the formation of the analytical signal lies in its participation in the formation of a multi-ligand Eu3+ complex on the surface of a nanoobject, which reduces the distance between the donor and the acceptor, as well as the additional removal of water molecules from the immediate environment of the complexing agent ion, suppressing the process of excitation energy dissipation. On the basis of the conducted researches the fluorimetric technique of definition of doxycycline in medicines is offered. It differs in a low limit of detection (6.0·10-9 M) and a wide range of the defined concentrations from 1.0·10-8 to 1.0·10-5 M.

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Vafaei, Saeid. "3D Nanoparticle Tracking Inside the Silver Nanofluid". Nanomaterials 10, nr 2 (24.02.2020): 397. http://dx.doi.org/10.3390/nano10020397.

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Movement of nanoparticle was investigated at the vicinity of silver nanofluid by using a microscope equipped with 100X lens. It was observed that silver nanoparticles were constantly moving inside the nanofluid for the first time. To explore the silver nanoparticle movement, the silver nanofluid was mixed with fluorescent nanoparticles. The coated nanoparticles were tracked three-dimensionally using a Delta Vision Elite inverted optical microscope. It was found that Marangoni flow was a possible reason of the nanoparticle movement which was generated by a gradient of the surface tension at the vicinity of the triple line. A gradient of the surface tension was formed by the segregation of the surfactant from the base liquid at the vicinity of the triple line. The surfactant was separated from the base liquid inside the triple region, since they have different affinities for the substrate. It was also shown that ring phenomenon took place when nanoparticle movement was weak or negligible.

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Swy, Eric R., Aaron S. Schwartz-Duval, Dorela D. Shuboni, Matthew T. Latourette, Christiane L. Mallet, Maciej Parys, David P. Cormode i Erik M. Shapiro. "Dual-modality, fluorescent, PLGA encapsulated bismuth nanoparticles for molecular and cellular fluorescence imaging and computed tomography". Nanoscale 6, nr 21 (2014): 13104–12. http://dx.doi.org/10.1039/c4nr01405g.

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Smith, Raven A., Rebecca C. Walker, Shani L. Levit i Christina Tang. "Single-Step Self-Assembly and Physical Crosslinking of PEGylated Chitosan Nanoparticles by Tannic Acid". Polymers 11, nr 5 (27.04.2019): 749. http://dx.doi.org/10.3390/polym11050749.

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Chitosan-based nanoparticles are promising materials for potential biomedical applications. We used Flash NanoPrecipitation as a rapid, scalable, single-step method to achieve self-assembly of crosslinked chitosan nanoparticles. Self-assembly was driven by electrostatic interactions, hydrogen bonding, and hydrophobic interactions; tannic acid served to precipitate chitosan to seed nanoparticle formation and crosslink the chitosan to stabilize the resulting particles. The size of the nanoparticles can be tuned by varying formulation parameters including the total solids concentration and block copolymer to core mass ratio. We demonstrated that hydrophobic moieties can be incorporated into the nanoparticle using a lipophilic fluorescent dye as a model system.

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Piyakulawat, Phimwipha, Duangporn Polpanich, Raweewan Thiramanas i Udom Asawapirom. "Preparation of Highly Monodisperse Polymeric Particles Incorporating Polymerizable Perylene-Bisimide Fluorophore". Advanced Materials Research 93-94 (styczeń 2010): 521–24. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.521.

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In this work, the yellow emitted perylene-bisimide dye with polymerizable functional groups was synthesized by condensation reaction of perylene tetracarboxylic acid dianhydride and allyl amine. The resulting polymerizable fluorophore was characterized in terms of structure with NMR and FT-IR, the absorption and emission properties by using UV-Vis and fluorescence spectroscopy, respectively. Afterwards, the reactive polymerizable fluorophore was incorporated into the polymer nanoparticle by copolymerization with styrene and acrylic acid monomers via miniemulsion polymerization. The obtained fluorescent nanoparticles was stable and showed a highly monodisperse size distribution with hydrodynamic diameter of 91.8±0.4 nm.

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