Artykuły w czasopismach: „Nanocrystal Design”

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Dâna, Aykutlu, Imran Akca, Atilla Aydinli, Rasit Turan i Terje G. Finstad. "A Figure of Merit for Optimization of Nanocrystal Flash Memory Design". Journal of Nanoscience and Nanotechnology 8, nr 2 (1.02.2008): 510–17. http://dx.doi.org/10.1166/jnn.2008.a156.

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Nanocrystals can be used as storage media for carriers in flash memories. The performance of a nanocrystal flash memory depends critically on the choice of nanocrystal size and density as well as on the choice of tunnel dielectric properties. The performance of a nanocrystal memory device can be expressed in terms of write/erase speed, carrier retention time and cycling durability. We present a model that describes the charge/discharge dynamics of nanocrystal flash memories and calculate the effect of nanocrystal, gate, tunnel dielectric and substrate properties on device performance. The model assumes charge storage in quantized energy levels of nanocrystals. Effect of temperature is included implicitly in the model through perturbation of the substrate minority carrier concentration and Fermi level. Because a large number of variables affect these performance measures, in order to compare various designs, a figure of merit that measures the device performance in terms of design parameters is defined as a function of write/erase/discharge times which are calculated using the theoretical model. The effects of nanocrystal size and density, gate work function, substrate doping, control and tunnel dielectric properties and device geometry on the device performance are evaluated through the figure of merit. Experimental data showing agreement of the theoretical model with the measurement results are presented for devices that has PECVD grown germanium nanocrystals as the storage media.

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Di Tocco, Aylén, Gabriela Valeria Porcal, Walter Iván Riberi, María Alicia Zon, Héctor Fernández, Sebastian Noel Robledo i Fernando Javier Arévalo. "Synthesis of stable CdS nanocrystals using experimental design: optimization of the emission". New Journal of Chemistry 43, nr 32 (2019): 12836–45. http://dx.doi.org/10.1039/c9nj02145k.

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He, Yizhou, Liyifei Xu, Cheng Yang, Xiaowei Guo i Shaorong Li. "Design and Numerical Investigation of a Lead-Free Inorganic Layered Double Perovskite Cs4CuSb2Cl12 Nanocrystal Solar Cell by SCAPS-1D". Nanomaterials 11, nr 9 (7.09.2021): 2321. http://dx.doi.org/10.3390/nano11092321.

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In the last decade, perovskite solar cells have made a quantum leap in performance with the efficiency increasing from 3.8% to 25%. However, commercial perovskite solar cells have faced a major impediment due to toxicity and stability issues. Therefore, lead-free inorganic perovskites have been investigated in order to find substitute perovskites which can provide a high efficiency similar to lead-based perovskites. In recent studies, as a kind of lead-free inorganic perovskite material, Cs4CuSb2Cl12 has been demonstrated to possess impressive photoelectric properties and excellent environmental stability. Moreover, Cs4CuSb2Cl12 nanocrystals have smaller effective photo-generated carrier masses than bulk Cs4CuSb2Cl12, which provides excellent carrier mobility. To date, there have been no reports about Cs4CuSb2Cl12 nanocrystals used for making solar cells. To explore the potential of Cs4CuSb2Cl12 nanocrystal solar cells, we propose a lead-free perovskite solar cell with the configuration of FTO/ETL/Cs4CuSb2Cl12 nanocrystals/HTL/Au using a solar cell capacitance simulator. Moreover, we numerically investigate the factors that affect the performance of the Cs4CuSb2Cl12 nanocrystal solar cell with the aim of enhancing its performance. By selecting the appropriate hole transport material, electron transport material, thickness of the absorber layer, doping density, defect density in the absorber, interface defect density, and working temperature point, we predict that the Cs4CuSb2Cl12 nanocrystal solar cell with the FTO/TiO2/Cs4CuSb2Cl12 nanocrystals/Cu2O/Au structure can attain a power conversion efficiency of 23.07% at 300 K. Our analysis indicates that Cs4CuSb2Cl12 nanocrystals have great potential as an absorbing layer towards highly efficient lead-free all-inorganic perovskite solar cells.

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Godfrey, William L., Yu-Zhong Zhang, Shulamit Jaron i Gayle M. Buller. "Qdot® nanocrystal conjugates in multispectral flow cytometry (42.14)". Journal of Immunology 182, nr 1_Supplement (1.04.2009): 42.14. http://dx.doi.org/10.4049/jimmunol.182.supp.42.14.

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Abstract Qdot® nanocrystal-antibody conjugates allow researchers to detect more parameters in a sample with manageable spectral overlap compensation between fluorophores. These semiconductor nanocrystals optimally excite with ultraviolet or violet light, and provide symmetrical emission peaks with up to 400 nm Stokes shifts. In this study, we review the use of Qdot® nanocrystal and conventional fluorophore conjugates with particular attention to filter selection to minimize the within-laser and cross-laser compensations. All experiments were performed using standard staining protocols with human peripheral blood leucocytes and analyzed using a BD LSR II flow cytometer. Example results: Qdot® 655 and Qdot® 605 nanocrystal conjugates require less than 5% compensation, and the Qdot® 655 nanocrystal can require <20% compensation versus APC. Qdot 705 nanocrystal requires >100% compensation versus RPE-Cy5.5, but filter selection can reduce compensation versus RPE-Alexa Fluor® 700 conjugates to <30%. By optimizing individual channels, 8 to 12 color experiments have been run with good resolution of cell populations using 2 to 4 Qdot® nanocrystal conjugates. The unique spectral characteristics of Qdot® nanocrystals can dramatically facilitate multicolor experimental design when performing multicolor flow cytometry experiments. Supported by Life Technologies Corporation.

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Sharma, Anju, i P. Sriganesan. "Formulation development and optimization of fast dissolving film containing carvedilol nanocrystals for improved bioavailability". Journal of Drug Delivery and Therapeutics 8, nr 6 (15.11.2018): 74–81. http://dx.doi.org/10.22270/jddt.v8i6.2017.

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In this work, fast dissolving films (FDF) were prepared using nanocrystal formulations in order to optimise dissolution properties of lipophilic, poorly soluble drug Cavedilol. Drug nanocrystals are crystals with a size in the nanometer range, meaning that they are nanoparticles with a crystalline character. Carvedilol nanosuspensions were prepared using a high-pressure homogenizer, and then encapsulated in to films by solvent casting method using polymers such as maltodextrin and PVA in different concentrations. Propylene glycol used as a plasticizer. This study aimed to develop and evaluate the formulation of FDF containing Carvedilol nanocrystals for enhanced bioavailability and better compliance. The formulation of FDF was optimized by Box-Behnken Design (BBD) (design expert 11.03).In this design, 13 formulas were performed. One of the formula were suggested by design expert desirability = 1. Keywords: Carvedilol, Nanocrystal, FDF, Box-bhenken optimization, in-vitro drug dissolution study,

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Kotian, Vinith, Marina Koland i Srinivas Mutalik. "Nanocrystal-Based Topical Gels for Improving Wound Healing Efficacy of Curcumin". Crystals 12, nr 11 (3.11.2022): 1565. http://dx.doi.org/10.3390/cryst12111565.

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Topical curcumin shows poor local availability because of its low aqueous solubility and inadequate tissue absorption. Curcumin nanocrystals were prepared by sonoprecipitation followed by lyophilization to improve surface area and solubility. The formulation was optimized by the Design of Experiment (DoE) approach. The nanocrystals were characterized for particle size, zeta potential, polydispersity index, scanning electron microscopy (SEM), powder x-ray diffraction (PXRD), practical yield and in vitro drug release studies. The nanocrystal-incorporated gel was evaluated for drug content, ex vivo permeation, in vivo skin irritation, and in vivo wound healing activity. Time of sonication and amplitude influenced the optimization of curcumin nanocrystals, but the effect of stabilizer concentrations was not significant beyond 0.5% w/w. SEM images of curcumin nanocrystals revealed irregular and plate-shaped particles with rough surfaces. PXRD patterns of curcumin nanocrystals showed low crystallinity compared to unprocessed curcumin powder. An in vitro drug release study demonstrated significant improvement in the percentage cumulative drug release in the form of nanocrystals compared to the unprocessed curcumin, and the release profile exhibited first-order kinetics. Curcumin nanocrystal gel showed 93.86% drug content and was free of skin irritation potential. Excision wound healing activity in albino rats showed that the curcumin nanocrystal gel exhibited significantly faster wound contraction than curcumin powder-incorporated gel.

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Li, Zhaohan, Zachary L. Robinson, Paolo Elvati, Angela Violi i Uwe R. Kortshagen. "Distance-dependent resonance energy transfer in alkyl-terminated Si nanocrystal solids". Journal of Chemical Physics 156, nr 12 (28.03.2022): 124705. http://dx.doi.org/10.1063/5.0079571.

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Understanding and controlling the energy transfer between silicon nanocrystals is of significant importance for the design of efficient optoelectronic devices. However, previous studies on silicon nanocrystal energy transfer were limited because of the strict requirements to precisely control the inter-dot distance and to perform all measurements in air-free environments to preclude the effect of ambient oxygen. Here, we systematically investigate the distance-dependent resonance energy transfer in alkyl-terminated silicon nanocrystals for the first time. Silicon nanocrystal solids with inter-dot distances varying from 3 to 5 nm are fabricated by varying the length and surface coverage of alkyl ligands in solution-phase and gas-phase functionalized silicon nanocrystals. The inter-dot energy transfer rates are extracted from steady-state and time-resolved photoluminescence measurements, enabling a direct comparison to theoretical predictions. Our results reveal that the distance-dependent energy transfer rates in Si NCs decay faster than predicted by the Förster mechanism, suggesting higher-order multipole interactions.

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Nakamura, Y., T. Ishibe, T. Taniguchi, T. Terada, R. Hosoda i Sh Sakane. "Semiconductor Nanostructure Design for Thermoelectric Property Control". International Journal of Nanoscience 18, nr 03n04 (28.03.2019): 1940036. http://dx.doi.org/10.1142/s0219581x19400362.

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We present the methodologies for developing high-performance thermoelectric materials using nanostructured interfaces by reviewing our three studies and giving the new aspect of nanostructuring results. (1) Connected Si nanocrystals exhibited ultrasmall thermal conductivity. The drastic thermal conductivity reduction was brought by phonon confinement and phonon scattering. Here, we present discussion about the new aspect for phonon transport: not only nanocrystal size but also shape can contribute to thermal conductivity reduction. (2) Si films including Ge nanocrystals demonstrated that phonon and carrier conductions were independently controlled in the films, where carriers were easily transported through the interfaces between Si and Ge, while phonons could be effectively scattered at the interfaces. (3) Embedded-ZnO nanowire structure demonstrated the simultaneous realization of power factor increase and thermal conductivity reduction. The [Formula: see text] increase was caused by the interface-dominated carrier transport. The nanowire interfaces also worked as phonon scatterers, resulting in the thermal conductivity reduction.

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Kovalenko, Maksym V. "Chemical Design of Nanocrystal Solids". CHIMIA International Journal for Chemistry 67, nr 5 (29.05.2013): 316–21. http://dx.doi.org/10.2533/chimia.2013.316.

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Matebie, Bisrat Yihun, Belachew Zegale Tizazu, Aseel A. Kadhem i S. Venkatesa Prabhu. "Synthesis of Cellulose Nanocrystals (CNCs) from Brewer’s Spent Grain Using Acid Hydrolysis: Characterization and Optimization". Journal of Nanomaterials 2021 (26.09.2021): 1–10. http://dx.doi.org/10.1155/2021/7133154.

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This study is aimed at utilizing brewery’s spent grain (BSG) byproduct for the synthesis of cellulose nanocrystals (CNCs) using acid hydrolysis and optimizing the hydrolysis parameters (hydrolysis time, temperature, liquid-solid ratio, and acid concentration). Alkali and bleaching treatment were done to remove hemicellulose and lignin from BSG. Optimization process was performed using central composite design (CCD) to obtain optimum value of cellulose nanocrystal (CNC) yield. The maximum cellulose nanocrystal (CNC) yield of 43.24% was obtained at optimum hydrolysis conditions of 50°C, 51 wt% acid concentration, 41 min, and liquid-solid ratio of 19 ml/g. The raw brewery spent grain; alkali-treated fiber, bleached fiber, and obtained CNC were characterized using scanning electron microscopy (SEM), XRD, particle analyzer, FTIR, and differential scanning calorimeter (DSC). The characterization results indicated that the obtained cellulose nanocrystal (CNC) has rod-like whisker shape with crystallinity of 76.3% and an average particle size of 309.4 nm.

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Mazumder, Rupa, i Swarnali Das Paul. "Formulation and Evaluation of Atenolol Nanocrystals Using 3(2) Full Factorial Design". Nanoscience & Nanotechnology-Asia 10, nr 3 (17.06.2020): 306–15. http://dx.doi.org/10.2174/2210681209666190220120053.

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Background: Atenolol is a commonly used antihypertensive drug of class III BCS category. It suffers from the problem of poor intestinal absorption or permeability thus low bioavailability. The objective of the present study was to enhance the permeability of atenolol by using a suitable technique, which is economical and devoid of using any organic solvent. Methods: The nanocrystal technology by high-pressure homogenization was chosen for this purpose, which is a less expensive and simple method. In this technique, no organic solvent was used. The study was further aimed to characterize prepared nanocrystals in the solid state by Fourier Transform Infrared Spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD) patterns, particle size, zeta potential, %yield and drug permeation study through isolated goat’s intestine. An in-vivo study was carried out to determine the pharmacokinetic property in comparison to pure drug powder using rats as experimental animals. The formulation design was optimized by a 3(2) factorial design. In these designs, two factors namely surfactant amount (X1) and speed of homogenizer (X2) were evaluated on three dependent variables namely particle size (y1), zeta potential (y2) and production yield (y3). Results: PXRD study indicated the presence of high crystal content in the prepared formulation. These nanocrystal formulations were found with a narrow size range from 125 nm to 652 nm and positive zeta potential of 16-18 mV. Optimized formulations showed almost 90% production yield. Permeability study revealed 90.88% drug release for optimized formulation in comparison to the pure drug (31.22%). The FTIR study also exposed that there was no disturbance in the principal peaks of the pure drug atenolol. This confirmed the integrity of the pure drug and its compatibility with the excipients used. A significant increase in the area under the concentration-time curve Cpmax and MRT for nanocrystals was observed in comparison to the pure drug. The higher values of the determination coefficient (R2) of all three parameters indicated the goodness of fit of the 3(2) factorial model. The factorial analysis also revealed that speed of homogenizer had a bigger effect on particle size (-0.2812), zeta potential (-0.0004) and production yield (0.0192) whereas amount of surfactant had a lesser effect on production yield (-370.4401), zeta potential (-43.3651) as well as particle size (-6169.2601). Conclusion: It is concluded that the selected method of nanocrystal formation and its further optimization by factorial design was effective to increase the solubility, as well as permeability of atenolol. Further, the systematic approach of factorial design provides rational evaluation and prediction of nanocrystals formulation on the selected limited number of smart experimentation.

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Amini, Ezatollah (Nima), i Mehdi Tajvidi. "Mechanical and thermal behavior of cellulose nanocrystals-incorporated Acrodur® sustainable hybrid composites for automotive applications". Journal of Composite Materials 54, nr 22 (22.03.2020): 3159–69. http://dx.doi.org/10.1177/0021998320912474.

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Utilization of cellulose nanocrystals as an additive in the formulation of biocomposites made with Acrodur® resin is presented. Natural fibers/polyethylene terephthalate mats were impregnated with Acrodur® and hot-pressed into the final thickness of 3 mm after drying. Biocomposites with 2 wt.% and 5 wt.% cellulose nanocrystal (dry-basis) were also produced. The produced biocomposite panels were then tested to determine the flexural strength, flexural modulus and Izod impact strength. The results revealed that adding cellulose nanocrystal to the composite formulation increased flexural modulus significantly up to 970 MPa (17.5% increase) at a panel density of 0.5 g/cm3, while it did not significantly affect flexural strength values. A slight reduction was observed in the impact strength of the samples by adding cellulose nanocrystal. The fractured samples of impact test were observed under a scanning electron microscope. It was shown that in all cases, the fracture happened due to the failure of the fibrous system and in particular natural fibers. Thermal stability of the composites was also investigated using thermo-gravimetric analysis. It was found that adding cellulose nanocrystal slightly reduced the thermal stability of the biocomposites. Potential compatibility of cellulose nanocrystal particles with Acrodur® resin is promising and the improvement in flexural modulus can lead to the design of lighter parts for automotive applications such as door panels, headliners, and underbody shields.

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Hou, Tuo-Hung, Chungho Lee, Venkat Narayanan, Udayan Ganguly i Edwin Chihchuan Kan. "Design Optimization of Metal Nanocrystal Memory—Part I: Nanocrystal Array Engineering". IEEE Transactions on Electron Devices 53, nr 12 (grudzień 2006): 3095–102. http://dx.doi.org/10.1109/ted.2006.885677.

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ZHANG, SHUANG-YUAN, MICHELLE D. REGULACIO, KWOK WEI SHAH, THAMMANOON SREETHAWONG, YUANGANG ZHENG i MING-YONG HAN. "COLLOIDAL PREPARATION OF MONODISPERSE NANOCRYSTALS". Journal of Molecular and Engineering Materials 02, nr 03n04 (wrzesień 2014): 1430001. http://dx.doi.org/10.1142/s2251237314300010.

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In the field of nanoscience, the ability to prepare high-quality nanocrystals is crucial for fundamental research and technology development. Herein, we review a general route for the colloidal preparation of monodisperse nanocrystals, which is divided into five different stages, namely (i) nucleation, (ii) growth, (iii) Ostwald ripening, (iv) surfactant capping and (v) precipitation. Each of the five stages is discussed in detail to provide a comprehensive understanding of the mechanism behind nanocrystal formation and the subsequent processing steps. We put emphasis on the classical theories and experimental techniques that are most frequently practiced. These are useful for the successful design and fabrication of nanocrystals with properties that are beneficial for use in a plethora of technological applications.

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Dhaval, Mori, Jalpa Makwana, Ekta Sakariya i Kiran Dudhat. "Drug Nanocrystals: A Comprehensive Review with Current Regulatory Guidelines". Current Drug Delivery 17, nr 6 (6.08.2020): 470–82. http://dx.doi.org/10.2174/1567201817666200512104833.

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Drug nanocrystals offer an attractive approach for improving the solubility and dissolution rate of poorly soluble drugs which accounts for nearly 40 % newly discovered drug molecules. Both methods for manufacturing drug nanocrystals have high industrial acceptability for being simple and easy to scale which is evident from the number of approved products available in the market. Ability to modify multiple aspects of dosage form like bioavailability, release pattern and dosage form requirement along with flexibility in choosing final dosage form starting from the tablet, capsule, suspension to parenteral one, have made nanocrystal technology one of the very promising and adaptable technology for dosage form design.

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NAGAI, Noriaki. "Design of Nanocrystal Based on Crystal Engineering". Hosokawa Powder Technology Foundation ANNUAL REPORT 27 (25.05.2020): 63–69. http://dx.doi.org/10.14356/hptf.17109.

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Kovalenko, Maksym V. "ChemInform Abstract: Chemical Design of Nanocrystal Solids". ChemInform 44, nr 41 (19.09.2013): no. http://dx.doi.org/10.1002/chin.201341217.

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Bhaskar, Rajveer, i Prakash Hiraman Patil. "NANOCRYSTAL SUSPENSION OF CEFIXIME TRIHYDRATE PREPARATION BY HIGH-PRESSURE HOMOGENIZATION FORMULATION DESIGN USING 23 FACTORIAL DESIGN". International Journal of Pharmacy and Pharmaceutical Sciences 9, nr 9 (13.07.2017): 64. http://dx.doi.org/10.22159/ijpps.2017v9i9.19319.

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Objective: In the present study, nanocrystal suspensions of cefixime trihydrate were prepared with the objective of providing increased solubility and stability with their nanoscopic size and thus developing the formulation of enhanced bioavailability potential.Methods: Nanocrystal suspensions were prepared by high-pressure homogenization technique using PVP K-30 as a stabilizer and evaluated for particle size, polydispersity index, zeta potential, permeation and drug release.Results: Particles of average size 143.5 nm having a polydispersity index of 0.269 were produced. Zeta potential was found to be −36.6 mV and the formulation was found stable on the basis of results obtained from differential scanning calorimetry and Fourier transform infrared spectroscopy studies. Optimized formulation showed 89.79 % and 88.38% drug lease and permeation respectively.Conclusion: The drug release and ex-vivo permeation studies revealed enhanced permeation of drug, as desired, indicating its potential for an attempt towards successful nano crystal formulation.

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Sarwar, Abdur Rehman, Furqan Muhammad Iqbal, Muhammad Anjum Jamil i Khizar Abbas. "Nanocrystals of Mangiferin Using Design Expert: Preparation, Characterization, and Pharmacokinetic Evaluation". Molecules 28, nr 15 (7.08.2023): 5918. http://dx.doi.org/10.3390/molecules28155918.

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Making nanoscale drug carriers could boost the bioavailability of medications that are slightly water soluble. One of the most promising approaches for enhancing the chemical stability and bioavailability of a variety of therapeutic medicines is liquid nanocrystal technology. This study aimed to prepare nanocrystals of mangiferin for sustained drug delivery and enhance the pharmacokinetic profile of the drug. The fractional factorial design (FFD) was used via a selection of independent and dependent variables. The selected factors were the concentration of mangiferin (A), hydroxypropyl methyl cellulose (HPMC) (B), pluronic acid (C), tween 80 (D), and the ratio of antisolvent to solvent (E). The selected responses were the particle size, polydispersity index (PDI), zeta potential, and entrapment efficiency. The nanocrystals were further evaluated for mangiferin release, release kinetics, Fourier transforms infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), particle size, zeta potential, and scanning electron microscopy (SEM). The stability studies of developed nanocrystals were performed for 6 months and pharmacokinetics on albino rabbits. The value of entrapment efficiencies ranged from 23.98% to 86.23%. The percentage release of mangiferin varied from 62.45 to 99.02%. FTIR and DSC studies showed the stability of mangiferin in the nanocrystals. The particle size of the optimized formulation was almost 100 nm and −12 mV the value of the zeta potential. The results of stability studies showed that the nanocrystals of mangiferin were stable for a period of six months. The peak plasma concentration of mangiferin from nanocrystals and suspension of mangiferin were 412 and 367 ng/mL, respectively. The value of AUC0−t of nanocrystals and suspension of mangiferin was 23,567.45 ± 10.876 and 18,976.12 ± 9.765 µg×h/mL, respectively, indicating that the nanocrystals of mangiferin showed greater availability of mangiferin compared to the suspension of the formulation. The developed nanocrystals showed a good release pattern of mangiferin, better stability studies, and enhanced the pharmacokinetics of the drug.

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Zhu, Yun-Pei, Tie-Zhen Ren, Tian-Yi Ma i Zhong-Yong Yuan. "Hierarchical Structures from Inorganic Nanocrystal Self-Assembly for Photoenergy Utilization". International Journal of Photoenergy 2014 (2014): 1–15. http://dx.doi.org/10.1155/2014/498540.

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Self-assembly has emerged as a powerful strategy for controlling the structure and physicochemical properties of ensembles of inorganic nanocrystals. Hierarchical structures from nanocrystal assembly show collective properties that differ from individual nanocrystals and bulk samples. Incorporation of structural hierarchy into nanostructures is of great importance as a result of enhancing mass transportation, reducing resistance to diffusion, and high surface areas for adsorption and reaction, and thus much effort has been devoted to the exploration of various novel organizing schemes through which inorganic porous structure with architectural design can be created. In this paper, the recent research progress in this field is reviewed. The general strategies for the synthesis of hierarchical structures assembled from nanobuilding blocks are elaborated. The well-defined hierarchical structures provide new opportunities for optimizing, tuning, and/or enhancing the properties and performance of these materials and have found applications in photoenergy utilization including photodegradation, photocatalytic H2production, photocatalytic CO2conversion, and sensitized solar cells, and these are discussed illustratively.

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Pardhi, Vishwas P., Tejesh Verma, S. J. S. Flora, Hardik Chandasana i Rahul Shukla. "Nanocrystals: An Overview of Fabrication, Characterization and Therapeutic Applications in Drug Delivery". Current Pharmaceutical Design 24, nr 43 (28.03.2019): 5129–46. http://dx.doi.org/10.2174/1381612825666190215121148.

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Approximately 40 % drugs in the market are having poor aqueous solubility related problems and 70 % molecules in discovery pipeline are being practically insoluble in water. Nanocrystals is a prominent tool to solve the issue related to poor aqueous solubility and helps in improving the bioavailability of many drugs as reported in the literature. Nanocrystals can be prepared by top down methods, bottom up methods and combination methods. Many patented products such as Nanocrystals®, DissoCubes®, NANOEDGE® and SmartCrystals ®, etc., are available, which are based on these three preparation methodologies. The particle size reduction resulted into unstable nanocrystalline system and the phenomenon of Ostawald ripening occurs. This instability issue could be resolved by using an appropriate stabilizers or combination of stabilizers. The nanosuspensions could be transformed to the solid state to prevent particle aggregation in liquid state by employing various unit operations such as lyophilisation, spray drying, granulation and pelletisation. These techniques are well known for their scalability and continuous nanocrystal formation advantages. Nanocrystals can be characterized by using scanning electron microscopy, transmission electron microscopy, atomic force microscopy, differential scanning calorimetry, fourier transform infrared spectroscopy, powdered x- ray diffraction and photon correlation spectroscopy. The downscaling of nanocrystals will enable rapid optimization of nanosuspension formulation in parallel screening design of preclinical developmental stage drug moieties. One of the most acceptable advantages of nanocrystals is their wide range of applicability such as oral delivery, ophthalmic delivery, pulmonary delivery, transdermal delivery, intravenous delivery and targeting (brain and tumor targeting). The enhancement in market value of nanocrystals as well as the amount of nanocrystal products in the market is gaining attention to be used as an approach in order to get commercial benefits.

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Luo, Dongxiang, Lin Wang, Ying Qiu, Runda Huang i Baiquan Liu. "Emergence of Impurity-Doped Nanocrystal Light-Emitting Diodes". Nanomaterials 10, nr 6 (24.06.2020): 1226. http://dx.doi.org/10.3390/nano10061226.

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In recent years, impurity-doped nanocrystal light-emitting diodes (LEDs) have aroused both academic and industrial interest since they are highly promising to satisfy the increasing demand of display, lighting, and signaling technologies. Compared with undoped counterparts, impurity-doped nanocrystal LEDs have been demonstrated to possess many extraordinary characteristics including enhanced efficiency, increased luminance, reduced voltage, and prolonged stability. In this review, recent state-of-the-art concepts to achieve high-performance impurity-doped nanocrystal LEDs are summarized. Firstly, the fundamental concepts of impurity-doped nanocrystal LEDs are presented. Then, the strategies to enhance the performance of impurity-doped nanocrystal LEDs via both material design and device engineering are introduced. In particular, the emergence of three types of impurity-doped nanocrystal LEDs is comprehensively highlighted, namely impurity-doped colloidal quantum dot LEDs, impurity-doped perovskite LEDs, and impurity-doped colloidal quantum well LEDs. At last, the challenges and the opportunities to further improve the performance of impurity-doped nanocrystal LEDs are described.

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Gandhi, Jaimini, Pooja Golwala, Shyam Madheshiya i Pranav Shah. "Nano-sizing Crystals: An Exquisite Way of Drug Conveyance". Nanoscience & Nanotechnology-Asia 10, nr 3 (17.06.2020): 203–18. http://dx.doi.org/10.2174/2210681209666190220130824.

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Extensive attempts have been made to decipher the problem associated with the solubility of drugs for maximizing bioavailability at targeted sites. More than 40% NCEs (new chemical entities) emerged through modern technology like high throughput screening, combinatorial chemistry, computer-aided drug design etc. and the drug discovery process has been dramatically accelerated. Fabrication of materials into the nanodimension changes their physical properties which depicts a vivid shift from lab scale optimization studies to scale up focused studies. In addition, this comprehensive review covers physics behind the drug nanocrystals and their properties, different technologies and methods of drug nanocrystal preparation and its stabilization along with theapplication of nanocrystals. This review also covers factors affecting nanoformulations, post-production processing and future prospects.

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Medinger, Joelle, Miroslava Nedyalkova i Marco Lattuada. "Solvothermal Synthesis Combined with Design of Experiments—Optimization Approach for Magnetite Nanocrystal Clusters". Nanomaterials 11, nr 2 (1.02.2021): 360. http://dx.doi.org/10.3390/nano11020360.

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Magnetite nanocrystal clusters are being investigated for their potential applications in catalysis, magnetic separation, and drug delivery. Controlling their size and size distribution is of paramount importance and often requires tedious trial-and-error experimentation to determine the optimal conditions necessary to synthesize clusters with the desired properties. In this work, magnetite nanocrystal clusters were prepared via a one-pot solvothermal reaction, starting from an available protocol. In order to optimize the experimental factors controlling their synthesis, response surface methodology (RSM) was used. The size of nanocrystal clusters can be varied by changing the amount of stabilizer (tribasic sodium citrate) and the solvent ratio (diethylene glycol/ethylene glycol). Tuning the experimental conditions during the optimization process is often limited to changing one factor at a time, while the experimental design allows for variation of the factors’ levels simultaneously. The efficiency of the design to achieve maximum refinement for the independent variables (stabilizer amount, diethylene glycol/ethylene glycol (DEG/EG) ratio) towards the best conditions for spherical magnetite nanocrystal clusters with desirable size (measured by scanning electron microscopy and dynamic light scattering) and narrow size distribution as responses were proven and tested. The optimization procedure based on the RSM was then used in reverse mode to determine the factors from the knowledge of the response to predict the optimal synthesis conditions required to obtain a good size and size distribution. The RSM model was validated using a plethora of statistical methods. The design can facilitate the optimization procedure by overcoming the trial-and-error process with a systematic model-guided approach.

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Talapin, Dmitri V. "Nanocrystal solids: A modular approach to materials design". MRS Bulletin 37, nr 1 (styczeń 2012): 63–71. http://dx.doi.org/10.1557/mrs.2011.337.

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Redding, Brandon, Shouyuan Shi, Tim Creazzo, Elton Marchena i Dennis W. Prather. "Design and characterization of silicon nanocrystal microgear resonators". Photonics and Nanostructures - Fundamentals and Applications 8, nr 3 (lipiec 2010): 177–82. http://dx.doi.org/10.1016/j.photonics.2010.04.004.

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Sommer, Sanna, Espen D. Bøjesen, Hazel Reardon i Bo B. Iversen. "Atomic Scale Design of Spinel ZnAl2O4 Nanocrystal Synthesis". Crystal Growth & Design 20, nr 3 (15.01.2020): 1789–99. http://dx.doi.org/10.1021/acs.cgd.9b01519.

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Liu, Z., C. Lee, V. Narayanan, G. Pei i E. C. Kan. "Metal nanocrystal memories. I. Device design and fabrication". IEEE Transactions on Electron Devices 49, nr 9 (wrzesień 2002): 1606–13. http://dx.doi.org/10.1109/ted.2002.802617.

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Gulsun, Tugba, Reyhan Neslihan Gursoy i Levent Oner. "Design and Characterization of Nanocrystal Formulations Containing Ezetimibe". CHEMICAL & PHARMACEUTICAL BULLETIN 59, nr 1 (2011): 41–45. http://dx.doi.org/10.1248/cpb.59.41.

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Li, Yin-Xiang, Xue-Mei Dong, Meng-Na Yu, Wei Liu, Yi-Jie Nie, Mustafa Eginligil, Ju-Qing Liu i in. "Enhanced emission in organic nanocrystals via asymmetrical design of spirocyclic aromatic hydrocarbons". Nanoscale 12, nr 18 (2020): 9964–68. http://dx.doi.org/10.1039/d0nr01436b.

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Lee, S. W., H. Joh, M. Seong, W. S. Lee, J. H. Choi i S. J. Oh. "Engineering surface ligands of nanocrystals to design high performance strain sensor arrays through solution processes". Journal of Materials Chemistry C 5, nr 9 (2017): 2442–50. http://dx.doi.org/10.1039/c7tc00230k.

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Peng, Shane X., Robert J. Moon i Jeffrey P. Youngblood. "Design and characterization of cellulose nanocrystal-enhanced epoxy hardeners". Green Materials 2, nr 4 (grudzień 2014): 193–205. http://dx.doi.org/10.1680/gmat.14.00015.

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Elbert, Katherine C., William Zygmunt, Thi Vo, Corbin M. Vara, Daniel J. Rosen, Nadia M. Krook, Sharon C. Glotzer i Christopher B. Murray. "Anisotropic nanocrystal shape and ligand design for co-assembly". Science Advances 7, nr 23 (czerwiec 2021): eabf9402. http://dx.doi.org/10.1126/sciadv.abf9402.

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The use of nanocrystal (NC) building blocks to create metamaterials is a powerful approach to access emergent materials. Given the immense library of materials choices, progress in this area for anisotropic NCs is limited by the lack of co-assembly design principles. Here, we use a rational design approach to guide the co-assembly of two such anisotropic systems. We modulate the removal of geometrical incompatibilities between NCs by tuning the ligand shell, taking advantage of the lock-and-key motifs between emergent shapes of the ligand coating to subvert phase separation. Using a combination of theory, simulation, and experiments, we use our strategy to achieve co-assembly of a binary system of cubes and triangular plates and a secondary system involving two two-dimensional (2D) nanoplates. This theory-guided approach to NC assembly has the potential to direct materials choices for targeted binary co-assembly.

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Sato, Kazuyoshi. "Nanocrystal Design for High Performance Solid Oxide Fuel Cells". Journal of the Society of Powder Technology, Japan 49, nr 1 (2012): 35–41. http://dx.doi.org/10.4164/sptj.49.35.

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Matsumura, Takashi, Atsushi Miura, Takio Hikono i Yukiharu Uraoka. "Forming Fe nanocrystals by reduction of ferritin nanocores for metal nanocrystal memory". AIP Advances 12, nr 5 (1.05.2022): 055029. http://dx.doi.org/10.1063/5.0092210.

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To fabricate metal nanocrystal (NC) memories based on iron ferritin proteins, we propose a method for embedding ferritin cores in SiO2 and performing a reduction process by rapid thermal annealing (RTA) in a hydrogen atmosphere. An iron oxide core biochemically synthesized by ferritin was used to fabricate a high-density memory node array of 7.7 × 1011 dots/cm2. Reduction intermediates and metallic iron NCs were obtained in a short time by using a hydrogen atmosphere RTA with the iron oxide core embedded in SiO2. Metal-oxide-semiconductor memory structures were fabricated, capacitance–voltage (C–V) measurements were performed, and hysteresis (memory window) suggesting charging and discharging of NCs was observed. Furthermore, the memory window and the charge injection threshold tended to vary depending on the reduction temperature. Since these values are proportional to the magnitude of the dot work function (or electron affinity), it is assumed that the formation of reduced intermediates NCs with varying work functions depending on the treatment temperature affects the electrical properties. The results suggest that the work function of the charge retention node can be controlled by reducing the metal oxide, enabling a new approach to memory design that actively employs the reduction process.

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Ben-Shahar, Yuval, Kathy Vinokurov, Héloïse de Paz-Simon, Yosef Gofer, Matan Leiter, Uri Banin i Yaron S. Cohen. "Photoelectrochemistry of colloidal Cu2O nanocrystal layers: the role of interfacial chemistry". J. Mater. Chem. A 5, nr 42 (2017): 22255–64. http://dx.doi.org/10.1039/c7ta06026b.

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Luo, Kaiying, Wanhua Wu, Sihang Xie, Yasi Jiang, Shengzu Liao i Donghuan Qin. "Building Solar Cells from Nanocrystal Inks". Applied Sciences 9, nr 9 (8.05.2019): 1885. http://dx.doi.org/10.3390/app9091885.

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The use of solution-processed photovoltaics is a low cost, low material-consuming way to harvest abundant solar energy. Organic semiconductors based on perovskite or colloidal quantum dot photovoltaics have been well developed in recent years; however, stability is still an important issue for these photovoltaic devices. By combining solution processing, chemical treatment, and sintering technology, compact and efficient CdTe nanocrystal (NC) solar cells can be fabricated with high stability by optimizing the architecture of devices. Here, we review the progress on solution-processed CdTe NC-based photovoltaics. We focus particularly on NC materials and the design of devices that provide a good p–n junction quality, a graded bandgap for extending the spectrum response, and interface engineering to decrease carrier recombination. We summarize the progress in this field and give some insight into device processing, including element doping, new hole transport material application, and the design of new devices.

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Tan, Zha Nao, Wen Qing Zhang, De Ping Qian, Hua Zheng, Sheng Qiang Xiao, Yong Ping Yang, Ting Zhu i Jian Xu. "Efficient Hybrid Infrared Solar Cells Based on P3HT and PbSe Nanocrystal Quantum Dots". Materials Science Forum 685 (czerwiec 2011): 38–43. http://dx.doi.org/10.4028/www.scientific.net/msf.685.38.

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The effects of composition on the performance of hybrid photovoltaic cells based on PbSe nanocrystal quantum dot(NQD)/ poly(3-hexylthiophene) nanocomposites were studied. The device performance and the absorption property strongly depended on the loading of PbSe. To improve the device performance, a pure light-absorbing P3HT film was inserted underneath the blended layer of P3HT and PbSe nanocrystal quantum dots in the active region. Such a design allowed for the employment of a thinner bulk heterojunction for more efficient carrier collection without an excessive reduction of the overall light absorption by the photovoltaic cell. The measured device performance showed a significant improvement over previously reported hybrid cells containing bulk heterojunctions of P3HT and Pb(S,Se) nanocrystal quantum dots.

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Chehaibou, Bilal, Eva Izquierdo, Audrey Chu, Claire Abadie, Mariarosa Cavallo, Adrien Khalili, Tung Huu Dang i in. "The complex optical index of PbS nanocrystal thin films and their use for short wave infrared sensor design". Nanoscale 14, nr 7 (2022): 2711–21. http://dx.doi.org/10.1039/d1nr07770h.

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Nobile, Concetta, i Pantaleo Davide Cozzoli. "Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials". Nanomaterials 12, nr 10 (18.05.2022): 1729. http://dx.doi.org/10.3390/nano12101729.

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Composite inorganic nanoarchitectures, based on combinations of distinct materials, represent advanced solid-state constructs, where coexistence and synergistic interactions among nonhomologous optical, magnetic, chemical, and catalytic properties lay a basis for the engineering of enhanced or even unconventional functionalities. Such systems thus hold relevance for both theoretical and applied nanotechnology-based research in diverse areas, spanning optics, electronics, energy management, (photo)catalysis, biomedicine, and environmental remediation. Wet-chemical colloidal synthetic techniques have now been refined to the point of allowing the fabrication of solution free-standing and easily processable multicomponent nanocrystals with sophisticated modular heterostructure, built upon a programmed spatial distribution of the crystal phase, composition, and anchored surface moieties. Such last-generation breeds of nanocrystals are thus composed of nanoscale domains of different materials, assembled controllably into core/shell or heteromer-type configurations through bonding epitaxial heterojunctions. This review offers a critical overview of achievements made in the design and synthetic elaboration of colloidal nanocrystal heterostructures based on diverse associations of transition metals (with emphasis on plasmonic metals) and transition-metal oxides. Synthetic strategies, all leveraging on the basic seed-mediated approach, are described and discussed with reference to the most credited mechanisms underpinning regioselective heteroepitaxial deposition. The unique properties and advanced applications allowed by such brand-new nanomaterials are also mentioned.

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Ouranidis, Andreas, Nikos Gkampelis, Catherine Markopoulou, Ioannis Nikolakakis i Kyriakos Kachrimanis. "Development of a Nanocrystal Formulation of a Low Melting Point API Following a Quality by Design Approach". Processes 9, nr 6 (27.05.2021): 954. http://dx.doi.org/10.3390/pr9060954.

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Preparation of nanocrystal formulations by wet media milling and spray-drying is a reliable technique to enhance dissolution and ameliorate absorption limitations of poorly soluble BCS II drugs. However, when thermosensitive compositions are dried at high temperatures, the risks of particle aggregation and thermal degradation must be considered. The present study investigates the effects of nanosuspension formulation variables when performing the spray drying process at equidistant temperatures above and below the melting point. Towards this purpose, Fenofibrate is exploited as a model drug of unfavorable pharmacokinetic profile and low melting point (79–82 °C), properties that render thermal processing a nontrivial task. Rationalizing the system’s behavior by combining molecular simulations with QbD methodology, the preparation of stable nanocrystals can be “steered” in order to avoid undesirable melting. The statistically resolved operational conditions showed that Fenofibrate Critical Quality Attribute–compliant nanosuspensions i.e., bearing hydrodynamic diameter and ζ-potential of 887 nm and −16.49 mV, respectively, were obtained by wet milling drug to Pharmacoat and mannitol weighted optimum ratios of 4.075% and 0.75%, after spray drying at the desired temperature of 77 °C. In conclusion, we present a quality assurance methodology of nano-comminution generally applicable for thermo-labile BCS II drugs.

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Xie, Renguo, Ute Kolb i Thomas Basché. "Design and Synthesis of Colloidal Nanocrystal Heterostructures with Tetrapod Morphology". Small 2, nr 12 (grudzień 2006): 1454–57. http://dx.doi.org/10.1002/smll.200600298.

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Lee, Changhwan, i P. James Schuck. "Photodarkening, Photobrightening, and the Role of Color Centers in Emerging Applications of Lanthanide-Based Upconverting Nanomaterials". Annual Review of Physical Chemistry 74, nr 1 (24.04.2023): 415–38. http://dx.doi.org/10.1146/annurev-physchem-082720-032137.

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Upconverting nanoparticles (UCNPs) compose a class of luminescent materials that utilize the unique wavelength-converting properties of lanthanide (Ln) ions for light-harvesting applications, photonics technologies, and biological imaging and sensing experiments. Recent advances in UCNP design have shed light on the properties of local color centers, both intrinsic and controllably induced, within these materials and their potential influence on UCNP photophysics. In this review, we describe fundamental studies of color centers in Ln-based materials, including research into their origins and their roles in observed photodarkening and photobrightening mechanisms. We place particular focus on the new functionalities that are enabled by harnessing the properties of color centers within Ln-doped nanocrystals, illustrated through applications in afterglow-based bioimaging, X-ray detection, all-inorganic nanocrystal photoswitching, and fully rewritable optical patterning and memory.

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Arvind, Gannimitta, Srinivas Prathima i Atla Venkateshwar Reddy. "Effect of Process Parameters on the Particle Size Distribution of Paclitaxel Nanocrystals". Advanced Science, Engineering and Medicine 12, nr 2 (1.02.2020): 137–46. http://dx.doi.org/10.1166/asem.2020.2480.

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The main intention of this work was to study the effect of process variables on the particle size distribution of paclitaxel nanocrystals. Paclitaxel nanocrystals were prepared by using anti-solvent precipitation method. Box Behnken design was used to optimize the process parameters including the Ratio (v/v) of two phases (A), Ulatrasonication time in min (B) and Surfactant concentration (%w/v) (C). A response surface methodology comprising 17 runs was carried out to optimize the nanocrystal formulation of paclitaxel. Two dependent variables particle size and polydispersity index (PDI) were identified as responses. Polynomial equations and response surface curves were used to relate the dependent and independent variables. The optimization model predicted a mean particle size of 147.653 nm and PDI of 0.1706 with A, B and C levels of 5, 15 min and 0.03% w/v respectively. The observed values were in close agreement with the predicted values. The optimized batches of nanocrystals were analyzed by FTIR, DSC and XRPD techniques. The optimized batch revealed irregular morphology as assessed by transmission electron microscopy and was crystalline as determined by thermal analysis and XRPD studies. Paclitaxel nanocrystals exhibited a considerable increase in solubility as well as dissolution rate in comparison with the pure drug. The present work thoroughly explored the influence of process parameters on the physicochemical characteristics of the produced drug nanocrystals.

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Smith, Ethan, Keith Hendren, James Haag, E. Foster i Stephen Martin. "Functionalized Cellulose Nanocrystal Nanocomposite Membranes with Controlled Interfacial Transport for Improved Reverse Osmosis Performance". Nanomaterials 9, nr 1 (20.01.2019): 125. http://dx.doi.org/10.3390/nano9010125.

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Thin-film nanocomposite membranes (TFNs) are a recent class of materials that use nanoparticles to provide improvements over traditional thin-film composite (TFC) reverse osmosis membranes by addressing various design challenges, e.g., low flux for brackish water sources, biofouling, etc. In this study, TFNs were produced using as-received cellulose nanocrystals (CNCs) and 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanocrystals (TOCNs) as nanoparticle additives. Cellulose nanocrystals are broadly interesting due to their high aspect ratios, low cost, sustainability, and potential for surface modification. Two methods of membrane fabrication were used in order to study the effects of nanoparticle dispersion on membrane flux and salt rejection: a vacuum filtration method and a monomer dispersion method. In both cases, various quantities of CNCs and TOCNs were incorporated into a polyamide TFC membrane via in-situ interfacial polymerization. The flux and rejection performance of the resulting membranes was evaluated, and the membranes were characterized via attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The vacuum filtration method resulted in inconsistent TFN formation with poor nanocrystal dispersion in the polymer. In contrast, the dispersion method resulted in more consistent TFN formation with improvements in both water flux and salt rejection observed. The best improvement was obtained via the monomer dispersion method at 0.5 wt% TOCN loading resulting in a 260% increase in water flux and an increase in salt rejection to 98.98 ± 0.41% compared to 97.53 ± 0.31% for the plain polyamide membrane. The increased flux is attributed to the formation of nanochannels at the interface between the high aspect ratio nanocrystals and the polyamide matrix. These nanochannels serve as rapid transport pathways through the membrane, and can be used to tune selectivity via control of particle/polymer interactions.

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Li, Yan. "(Invited, Digital Presentation) Uniqueness of Cobalt-Tungsten Intermetallic Compounds in Catalyzing Single-Walled Carbon Nanotube Growth". ECS Meeting Abstracts MA2022-01, nr 10 (7.07.2022): 765. http://dx.doi.org/10.1149/ma2022-0110765mtgabs.

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The intermetallic Co7W6 catalysts have shown great success in chirality-specified growth of single-walled carbon nanotubes (SWCNTs). Electron microscopic techniques, particularly the in-situ techniques enable us to study the growth mechanism and the behavior of catalysts at atomic scale. It was found that the structure of Co7W6 nanocrystals were stable at the temperature of 1100 °C under carbon feeding condition. No carbon dispersion within the nanocrystal happened. These observations illustrate why such kind of catalysts can act as the structural template to grow SWCNTs with specified chiralities. Due to the less efficient carbon diffusion and supply on the surface of catalysts in such a vapor-solid-solid process than that in a vapor-liquid-solid process, SWCNTs normally nucleate on larger catalyst nanocrystals. All these behaviors are distinctly different from those of normal metallic catalysts, demonstrating the uniqueness of intermetallic Co7W6 catalysts in chirality-selective growth of SWCNTs. These results can help us to further understand the mechanism of the origination of chirality selectivity in SWCNT growth, benefiting the rational design of catalysts.

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Ruggeri, Marco, Rita Sánchez-Espejo, Luca Casula, Raquel de Melo Barbosa, Giuseppina Sandri, Maria Cristina Cardia, Francesco Lai i César Viseras. "Clay-Based Hydrogels as Drug Delivery Vehicles of Curcumin Nanocrystals for Topical Application". Pharmaceutics 14, nr 12 (17.12.2022): 2836. http://dx.doi.org/10.3390/pharmaceutics14122836.

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The poor water solubility of a significant number of active pharmaceutical ingredients (API) remains one of the main challenges in the drug development process, causing low bioavailability and therapeutic failure of drug candidates. Curcumin is a well-known Biopharmaceutics Classification System (BCS) class IV drug, characterized by lipophilicity and low permeability, which hampers topical bioavailability. Given these premises, the aim of this work was the design and the development of curcumin nanocrystals and their incorporation into natural inorganic hydrogels for topical application. Curcumin nanocrystals were manufactured by the wet ball milling technique and then loaded in clay-based hydrogels. Bentonite and/or palygorskite were selected as the inorganic gelling agents. Curcumin nanocrystal-loaded hydrogels were manufactured by means of a homogenization process and characterized with respect to their chemico-physical properties, in vitro release, antioxidant activity and skin permeation. The results highlighted that the presence of bentonite provided an increase of curcumin skin penetration and simultaneously allowed its radical scavenging properties, due to the desirable rheological characteristics, which should guarantee the necessary contact time of the gel with the skin.

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Zhao, Litao, Yu Chen, Xiantong Yu, Xiao Xing, Jinquan Chen, Jun Song i Junle Qu. "Low-threshold stimulated emission in perovskite quantum dots: single-exciton optical gain induced by surface plasmon polaritons at room temperature". Journal of Materials Chemistry C 8, nr 17 (2020): 5847–55. http://dx.doi.org/10.1039/d0tc00198h.

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The surface plasmon polaritons induced single-exciton lasing of lead halide perovskite QDs in room temperature may provide a new concept for the further design of low threshold stimulated emission colloidal nanocrystal lasers.

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Ainurofiq, Ahmad, Yuniawan Hidayat, Eva Y. P. Lestari, Mayasri M. W. Kumalasari i Syaiful Choiri. "Resveratrol Nanocrystal Incorporated into Mesoporous Material: Rational Design and Screening through Quality-by-Design Approach". Nanomaterials 12, nr 2 (10.01.2022): 214. http://dx.doi.org/10.3390/nano12020214.

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Bioflavonoids from grape seeds feature powerful antioxidant and immunostimulant activities, but they present problems related to solubility and bioavailability. Nanocrystal (NC) incorporated into a mesoporous carrier is a promising strategy to address these issues. However, the preparation of this formulation involves the selection of factors affecting its critical quality attributes. Hence, this study aimed to develop an NC formulation incorporating resveratrol into a soluble mesoporous carrier based on rational screening design using a systematic and continuous development process, the quality-by-design paradigm. A mesoporous soluble carrier was prepared by spray-drying mannitol and ammonium carbonate. The NC was obtained by introducing the evaporated solvent containing a drug/polymer/surfactant and mesoporous carrier to the medium. A 26−2 fractional factorial design (FFD) approach was carried out in the screening process to understand the main effect factors. The type and concentration of polymer and surfactant, resveratrol loading, and solvent were determined on the NC characteristics. The results indicated that drug loading, particle size, and solubility were mainly affected by RSV loading, PEG concentration, and Kolliphor EL concentration. The polymer contributed dominantly to reducing the particle size and enhancing solubility in this screening design. The presence of surfactants in this system made it possible to prolong the supersaturation process. According to the 26−2 FFD, the factors selected to be further developed using a statistical technique according to the quality-by design-approach, Box Behnken Design, were Kolliphor EL, PEG400, and RSV loading.

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Murray, Christopher B., Daniel Rosen, Jennifer D. Lee, Katherine C. Elbert i Benjanin Hammel. "(Keynote) Nanocrystal Design and Self-Assembly in Service of Heterogeneous Catalysis". ECS Meeting Abstracts MA2021-01, nr 23 (30.05.2021): 887. http://dx.doi.org/10.1149/ma2021-0123887mtgabs.

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