Статті в журналах: "Photothermal IR spectroscopy"

1

Buck, M., B. Schäfer, and P. Hess. "Photothermal desorption spectroscopy with IR lasers." Surface Science Letters 161, no. 1 (October 1985): A541. http://dx.doi.org/10.1016/0167-2584(85)90525-0.

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2

Buck, M., B. Schäfer, and P. Heis. "Photothermal desorption spectroscopy with IR lasers." Surface Science 161, no. 1 (October 1985): 245–54. http://dx.doi.org/10.1016/0039-6028(85)90740-x.

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3

Anderson, Mark S. "Infrared Spectroscopy with an Atomic Force Microscope." Applied Spectroscopy 54, no. 3 (March 2000): 349–52. http://dx.doi.org/10.1366/0003702001949618.

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An atomic force microscope (AFM) has been used to measure the modulated photothermal displacement of a surface, thus acting as a local detector. This was demonstrated with Fourier transform infrared (FT-IR) and filter spectrometers focused on various samples. Similarly, surface layers were removed by an AFM and analyzed by the photothermal deformation of the coated cantilever. This work shows that the AFM can function as both an infrared detector and a precise surface separation device for spectroscopic analysis. The AFM combined with an FT-IR has the potential to enhance the sensitivity, selectivity, and spatial resolution of infrared spectroscopy.

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4

Mandelis, A., F. Boroumand, H. Solka, J. Highfield, and H. Van Den Bergh. "Fourier Transform Infrared Photopyroelectric Spectroscopy of Solids: A New Technique." Applied Spectroscopy 44, no. 1 (January 1990): 132–43. http://dx.doi.org/10.1366/0003702904085778.

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A novel analytical technique, Fourier transform infrared photopyroelectric spectroscopy (FT-IR-P2ES) is demonstrated and applied to spectroscopic investigations of solid materials. The salient features of the technique and its advantages over other conventional FT-IR photothermal methods are discussed. A few selected quantitative applications are presented as examples of the versatility and sensitivity of the new technique.

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5

Hertzberg, Otto, Alexander Bauer, Arne Küderle, Miguel A. Pleitez, and Werner Mäntele. "Depth-selective photothermal IR spectroscopy of skin: potential application for non-invasive glucose measurement." Analyst 142, no. 3 (2017): 495–502. http://dx.doi.org/10.1039/c6an02278b.

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Photothermal depth profiling is applied to total internal reflection enhanced photothermal deflection spectroscopy (TIR-PTDS) in order to study skin characteristicsin vivoand to improve the sensing technique for non-invasive glucose monitoring.

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6

Pleitez, M. A., O. Hertzberg, A. Bauer, M. Seeger, T. Lieblein, H. v. Lilienfeld-Toal, and W. Mäntele. "Photothermal deflectometry enhanced by total internal reflection enables non-invasive glucose monitoring in human epidermis." Analyst 140, no. 2 (2015): 483–88. http://dx.doi.org/10.1039/c4an01185f.

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We present an IR-pump/VIS-probe method for the measurement of ir absorption spectra by means of photothermal deflectometry (ptd) enhanced by total internal reflection (tir). This technique is termed tir-ptd spectroscopy.

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7

Smith, Matthew J., Christopher J. Manning, Richard A. Palmer, and James L. Chao. "Step Scan Interferometry in the Mid-Infrared with Photothermal Detection." Applied Spectroscopy 42, no. 4 (May 1988): 546–55. http://dx.doi.org/10.1366/0003702884429184.

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A medium resolution mid-infrared FT-IR instrument (IBM Instruments IR 44) has been modified to do step scanning; this has been done with the use of concepts previously applied to both near- and far-infrared instruments. In this paper we illustrate the method used for driving the mirror in the step scan mode and present some preliminary results from using the instrument with photothermal detection. At the current state of development, results obtained with the use of phase modulation indicate that this method produces significantly higher signal-to-noise ratios than does the use of amplitude (chopper) modulation to generate the photothermal signal.

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8

Garcia, Jose A., Andreas Mandelis, Margarita Marinova, Kirk H. Michaelian, and Shapour Afrashtehfar. "Quantitative Photothermal Radiometric and FT-IR Photoacoustic Measurements of Specialty Papers." Applied Spectroscopy 52, no. 9 (September 1998): 1222–29. http://dx.doi.org/10.1366/0003702981945048.

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Frequency-domain laser infrared photothermal radiometry (PTR) and photoacoustic Fourier transform spectroscopy (FT-IR/PAS) were used for the measurement of the thermophysical properties (thermal diffusivity, α, and conductivity, k) of specialty paper samples with various cotton contents. An improved one-dimensional photothermal model of a free-standing sheet of paper in air that includes both the transmission and backscattering mode was introduced. A high degree of accuracy and reliability was obtained when a multiparameter-fit optimization algorithm was used to examine the transmission and backscattered PTR experimental results. The ability to measure α and its variation, Δα, as a result of the manufacturing process via the PTR technique is invaluable in terms of the quality control of paper products.

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9

Mathurin, Jeremie, Ariane Deniset-Besseau, Dominique Bazin, Emmanuel Dartois, Martin Wagner, and Alexandre Dazzi. "Photothermal AFM-IR spectroscopy and imaging: Status, challenges, and trends." Journal of Applied Physics 131, no. 1 (January 7, 2022): 010901. http://dx.doi.org/10.1063/5.0063902.

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10

Youn, Jong-In, and Thomas E. Milner. "Evaluation of photothermal effects in cartilage using FT-IR spectroscopy." Lasers in Medical Science 23, no. 3 (August 3, 2007): 229–35. http://dx.doi.org/10.1007/s10103-007-0464-8.

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11

Varlashkin, P. G., and M. J. D. Low. "FT-IR Photothermal Beam Deflection Spectroscopy of Solids Submerged in Liquids." Applied Spectroscopy 40, no. 8 (November 1986): 1170–76. http://dx.doi.org/10.1366/0003702864507783.

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FT-IR photothermal beam deflection (PBD) spectra were recorded of solids submerged in liquid CCl4 and in C2Cl4. Some PBD effects are described. Submerging the sample leads to PBD signals 40 times larger than those found with the sample in air, but the signal-to-noise ratio of FT-IR/PBD spectra is only increased by a factor of ten. Certain aspects of the technique and its utility are discussed.

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12

Palmer, Richard A., and Matthew J. Smith. "Rapid-scanning Fourier-transform infrared spectroscopy with photothermal beam-deflection (mirage effect) detection at the solid–liquid interface." Canadian Journal of Physics 64, no. 9 (September 1, 1986): 1086–92. http://dx.doi.org/10.1139/p86-187.

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Photothermal beam-deflection (mirage effect) detection in the mid-infrared with a commercial scanning Fourier-transform infrared spectrometer has been used to characterize various solid–liquid interface and surface-bound species. The inherently unfavorable ambient noise level and relatively high Fourier (photothermal modulation) frequencies associated with commercial scanning instrumentation are compensated by the thermal and refractive properties of the liquid beam-deflection medium, which enhance the signal. Preliminary results described illustrate the potential of the technique for infrared (IR) studies of electrochemistry, catalysis, corrosion, and other surface modifications, as well as for polarized IR single-crystal spectra.

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13

Low, M. J. D., and C. Morterra. "Infrared Surface Studies of Opaque or Scattering Materials Using Photothermal Beam Deflection Spectroscopy." Adsorption Science & Technology 2, no. 2 (June 1985): 131–50. http://dx.doi.org/10.1177/026361748500200206.

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Infrared (IR) photothermal beam deflection spectroscopy (PBDS) is briefly described and some of its applications to studies of carbons and highly scattering materials are reviewed. PBDS is especially useful for the study of materials which absorb IR radiation very strongly or act as strong IR scatterers, so that conventional IR techniques fail. Application of PBDS to study the thermal degradation of a phenol-formaldehyde resin, the reaction of NH3 and H2O with the surfaces of intermediate-temperature chars, the effect of Fe3+ on the charring of cellulose, the dehydration of titanyl sulphate, and TiO2 pigments, are described.

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14

Takahashi, Makoto, Yasuo Okuzawa, Masaaki Fujii, and Mitsuo Ito. "Thermal lensing and photoacoustic spectra of gaseous acetylene by pulsed tunable infrared laser." Canadian Journal of Chemistry 69, no. 11 (November 1, 1991): 1656–58. http://dx.doi.org/10.1139/v91-243.

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Thermal lensing and photoacoustic spectra of ν3, ν1 + 3, and ν1 + ν2 + ν3 vibrational transitions of gaseous acetylene were observed by a tunable pulsed IR laser converted from a pulsed dye laser. Application of a pulsed IR laser to photothermal spectroscopy is demonstrated. Key words: thermal lensing spectra, photoacoustic spectra, pulsed tunable infrared laser.

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15

Salnick, Alex O., and Werner Faubel. "Photoacoustic FT-IR Spectroscopy of Natural Copper Patina." Applied Spectroscopy 49, no. 10 (October 1995): 1516–24. http://dx.doi.org/10.1366/0003702953965461.

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Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) has proved to be a useful tool for nondestructive testing of copper corrosion layer (patina) formed in the atmosphere. The samples cut from a piece of the roof of the Stockholm City Hall were examined without any additional pretreatment. The components of the patina—brochantite Cu4(OH)6SO4, antlerite Cu3(OH)4SO4, and basic cupric carbonate Cu2CO3(OH)6 · H2O—as well as some other minerals were identified. The photothermal beam deflection (PBD) method was used for independent photoacoustic characterization of the samples. The depth profiling capability of FT-IR/PAS was used to determine the degree of photoacoustic saturation of the spectral bands and to evaluate the depth distribution of the main patina components. The technique thus compares favorably with more common approaches of patina examination which are more expensive and require special sample preparation.

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16

Varlashkin, P. G., and M. J. D. Low. "FT-IR Photothermal Beam Deflection Spectroscopy of Black Inks on Paper." Applied Spectroscopy 40, no. 4 (May 1986): 507–13. http://dx.doi.org/10.1366/0003702864508999.

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Infrared spectra of several different black inks on paper were obtained by FT-IR photothermal beam deflection spectroscopy (PBDS). Even though the manuscript samples contained about 0.1–0.5 μg of ink solid, spectra of sufficient quality were obtained to enable us to tell which inks contain carbon and to permit some differentiation between similar black inks to be made. However, the identification of an unknown ink is not feasible at present. Spectra of the ink printed on two stamps, and of the black print of a dollar bill, were also recorded. IR/PBDS studies of manuscript and print are totally nondestructive, and may prove to be useful in the fields of forensics and art history.

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17

Varlashkin, P. G., M. J. D. Low, G. A. Parodi, and C. Morterra. "A Comparison of FT-IR/PA and FT-IR/PBD Spectra of Powders." Applied Spectroscopy 40, no. 5 (July 1986): 636–41. http://dx.doi.org/10.1366/0003702864508539.

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FT-IR photoacoustic (PA) and also photothermal beam deflection (PBD) spectra were recorded with the same particulate samples (graphite, charcoal, aspirin, and silica) under the same conditions in order to compare the quality of the spectra obtainable with the two techniques. A PA cell fitted with windows for the PBD laser probe beam was used, and PA and PBD spectra of each sample were recorded at 8 cm−1 resolution at each of the four different interferometer scan velocities. Although the overall aspects of FT-IR/PA and FT-IR/PBD spectra are the same, the signal-to-noise ratios of PA spectra are appreciably better than those of PBD spectra because PBD detection is more prone to disturbance by vibration than is PA detection. Absorption bands appear at the same wavenumbers in PA and PBD spectra. However, the relative intensities of bands of PBD spectra depend on the absorptive properties of the powdered solids; with weak absorbers, some bands may not be detected at all. PAS can be used with all powders. PBDS is of little or no use for the examination of weakly absorbing powders unless they scatter IR radiation extensively.

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18

B R, Venugopal. "Immobilization of Metal Sulfide Nanocrystals on Multiwalled Carbon Nanotubes Facilitated by Infrared Irradiation." Mapana - Journal of Sciences 13, no. 2 (July 7, 2017): 17–32. http://dx.doi.org/10.12723/mjs.29.2.

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Uniformly distributed metal sulfide nanocrystals are immobilized on the surface of oxygenated multiwalled carbon nanotubes (MWCNTs) by reacting metal ions (Cu 2+ / Zn 2+ /Cd 2+ ) anchored to MWCNTs with hydrogen sulfide while irradiating with infrared (IR) radiation. The IR irradiation is the key step in the effective immobilization of metal sulfide nanocrystals on MWCNTs. The photoabsorption and photothermal properties of MWCNTs in the presence of IR irradiation raises the temperature of the CNTs in solution, facilitating the interaction between the acidic groups on CNTs and the metal ions, which results in effective immobilization of the nanocrystals. The metal sulfide-MWCNT hybrids are characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, scanning and transmission electron microscopy.

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19

Hammiche, A., H. M. Pollock, M. Reading, M. Claybourn, P. H. Turner, and K. Jewkes. "Photothermal FT-IR Spectroscopy: A Step towards FT-IR Microscopy at a Resolution Better Than the Diffraction Limit." Applied Spectroscopy 53, no. 7 (July 1999): 810–15. http://dx.doi.org/10.1366/0003702991947379.

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20

Mankar, Rupali, Chalapathi C. Gajjela, Carlos E. Bueso-Ramos, C. Cameron Yin, David Mayerich, and Rohith K. Reddy. "Polarization Sensitive Photothermal Mid-Infrared Spectroscopic Imaging of Human Bone Marrow Tissue." Applied Spectroscopy 76, no. 4 (March 2, 2022): 508–18. http://dx.doi.org/10.1177/00037028211063513.

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Collagen quantity and integrity play an important role in understanding diseases such as myelofibrosis (MF). Label-free mid-infrared spectroscopic imaging (MIRSI) has the potential to quantify collagen while minimizing the subjective variance observed with conventional histopathology. Infrared (IR) spectroscopy with polarization sensitivity provides chemical information while also estimating tissue dichroism. This can potentially aid MF grading by revealing the structure and orientation of collagen fibers. Simultaneous measurement of collagen structure and biochemical properties can translate clinically into improved diagnosis and enhance our understanding of disease progression. In this paper, we present the first report of polarization-dependent spectroscopic variations in collagen from human bone marrow samples. We build on prior work with animal models and extend it to human clinical biopsies with a practical method for high-resolution chemical and structural imaging of bone marrow on clinical glass slides. This is done using a new polarization-sensitive photothermal mid-infrared spectroscopic imaging scheme that enables sample and source independent polarization control. This technology provides 0.5 µm spatial resolution, enabling the identification of thin (≈1 µm) collagen fibers that were not separable using Fourier Transform Infrared (FT-IR) imaging in the fingerprint region at diffraction-limited resolution ( ≈ 5 µm). Finally, we propose quantitative metrics to identify fiber orientation from discrete band images (amide I and amide II) measured under three polarizations. Previous studies have used a pair of orthogonal polarization measurements, which is insufficient for clinical samples since human bone biopsies contain collagen fibers with multiple orientations. Here, we address this challenge and demonstrate that three polarization measurements are necessary to resolve orientation ambiguity in clinical bone marrow samples. This is also the first study to demonstrate the ability to spectroscopically identify thin collagen fibers (≈1 µm diameter) and their orientations, which is critical for accurate grading of human bone marrow fibrosis.

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21

Tai, Fangfang, Kota Koike, Hiroyuki Kawagoe, Jun Ando, Yasuaki Kumamoto, Nicholas I. Smith, Mikiko Sodeoka, and Katsumasa Fujita. "Detecting nitrile-containing small molecules by infrared photothermal microscopy." Analyst 146, no. 7 (2021): 2307–12. http://dx.doi.org/10.1039/d0an02198a.

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We demonstrated IR photothermal imaging of trifluoromethoxy carbonyl cyanide phenylhydrazone (FCCP) in cells. The result indicates that a nitrile group can be used as a vibrational tag to image target molecules.

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22

Low, M. J. D., and C. Morterra. "Some Practical Aspects of FT-IR/PBDS. Part II: Sample Handling Procedures." Applied Spectroscopy 41, no. 2 (February 1987): 280–87. http://dx.doi.org/10.1366/000370287774986813.

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FT-IR photothermal beam deflection spectroscopy (PBDS) is truly nondestructive in that none of the sample preparation methods needed for the IR examination of solids are mandated. Such nondestructive examination is, however, inefficient—in that long scanning times are frequently needed—and is not really required with many samples. If it is permissible to subject the sample to a simple hand grinding, efficiency can be greatly improved. Sample preparation and handling are discussed, and the peculiarities of certain samples are described. Particular emphasis is placed on the necessity of proper sample handling for surface studies, data of the vacuum pyrolysis of polyvinyledene being used as example.

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23

Peoples, Margie E., Matthew J. Smith, and Richard A. Palmer. "FT-IR Photothermal Beam Deflection Spectroscopy (PBDS) Studies of Polymer-Modified Graphite Electrodes." Applied Spectroscopy 41, no. 7 (September 1987): 1257–59. http://dx.doi.org/10.1366/0003702874447608.

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24

Bhattarai, Deval Prasad, and Beom Su Kim. "NIR-Triggered Hyperthermal Effect of Polythiophene Nanoparticles Synthesized by Surfactant-Free Oxidative Polymerization Method on Colorectal Carcinoma Cells." Cells 9, no. 9 (September 18, 2020): 2122. http://dx.doi.org/10.3390/cells9092122.

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In this work, polythiophene nanoparticles (PTh–NPs) were synthesized by a surfactant-free oxidative chemical polymerization method at 60 °C, using ammonium persulphate as an oxidant. Various physicochemical properties were studied in terms of field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier transform infra-red (FT-IR) spectroscopy, and differential scanning calorimetry (DSC)/thermogravimetric analysis (TGA). Photothermal performance of the as-synthesized PTh–NPs was studied by irradiating near infra-red of 808 nm under different concentration of the substrate and power supply. The photothermal stability of PTh–NPs was also studied. Photothermal effects of the as-synthesized PTh–NPs on colorectal cancer cells (CT-26) were studied at 100 µg/mL concentration and 808 nm NIR irradiation of 2.0 W/cm2 power. Our in vitro results showed remarkable NIR laser-triggered photothermal apoptotic cell death by PTh–NPs. Based on the experimental findings, it is revealed that PTh–NPs can act as a heat mediator and can be an alternative material for photothermal therapy in cancer treatment.

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25

Einsiedel, Heiko, Maximilian Kreiter, Mario Leclerc, and Silvia Mittler-Neher. "Photothermal beam deflection spectroscopy in the near IR on poly[3-alkylthiophene]s." Optical Materials 10, no. 1 (March 1998): 61–68. http://dx.doi.org/10.1016/s0925-3467(97)00141-9.

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26

Low, M. J. D. "Some Practical Aspects of FT-IR/PBDS Part I: Vibrational Noise." Applied Spectroscopy 40, no. 7 (September 1986): 1011–19. http://dx.doi.org/10.1366/0003702864508052.

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FT-IR photothermal beam deflection (PBD) signals are several orders of magnitude smaller than PBD signals generated in other spectral regions and by other means, so that vibrational rather than electronic noise is important to the production of FT-IR/PBD spectra at present. The interferometer of the PBD spectrometer produces mechanical vibrations, but the most serious disturbances arise in the environment and are of unknown origin and uncontrollable. The mechanical vibrations imposed on the optics lead to random, broad-band noise which can be decreased by multiple scanning, as well as to noise at discrete frequencies which can be nonrandom and consequently not be diminished by multiple scanning. Some types of such noise and their effects are described and discussed.

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27

Sowa, Michael G., and Henry H. Mantsch. "FT-IR Step-Scan Photoacoustic Phase Analysis and Depth Profiling of Calcified Tissue." Applied Spectroscopy 48, no. 3 (March 1994): 316–19. http://dx.doi.org/10.1366/0003702944028182.

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Rapid-scan- and step-scan-based Fourier transform infrared photoacoustic depth profiling results of an extracted but intact human tooth are compared. The effects of various data processing methods are examined. Analysis of the phase dispersion of the photothermal signal along with spectral linearization is used to access the extent of photoacoustic saturation in the photoacoustic spectra. Phase-modulated/phase-resolved depth profiling methods are less prone to photoacoustic saturation and provide superior localization of the surface and subsurface absorbers distributed in the tooth enamel. Mid-infrared depth profiling studies of calcified tissues can aid in the understanding of degenerative bone diseases, bone growth, and modeling, as well as tissue mineralization.

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28

Zhu, Wenhui, Caiyun Zhang, Yali Chen, and Qiliang Deng. "Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue." Polymers 13, no. 4 (February 13, 2021): 558. http://dx.doi.org/10.3390/polym13040558.

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Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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29

Amatya, Reeju, Seungmi Hwang, Taehoon Park, Kyoung Ah Min, and Meong Cheol Shin. "In Vitro and In Vivo Evaluation of PEGylated Starch-Coated Iron Oxide Nanoparticles for Enhanced Photothermal Cancer Therapy." Pharmaceutics 13, no. 6 (June 12, 2021): 871. http://dx.doi.org/10.3390/pharmaceutics13060871.

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Iron oxide nanoparticles (IONPs) possess versatile utility in cancer theranostics, thus, they have drawn enormous interest in the cancer research field. Herein, we prepared polyethylene glycol (PEG)-conjugated and starch-coated IONPs (“PEG–starch–IONPs”), and assessed their applicability for photothermal treatment (PTT) of cancer. The prepared PEG–starch–IONPs were investigated for their physical properties by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and dynamic light scattering (DLS). The pharmacokinetic study results showed a significant extension in the plasma half-life by PEGylation, which led to a markedly increased (5.7-fold) tumor accumulation. When PEG–starch–IONPs were evaluated for their photothermal activity, notably, they displayed marked and reproducible heating effects selectively on the tumor site with laser irradiation. Lastly, efficacy studies demonstrated that PEG–starch–IONPs-based PTT may be a promising mode of cancer therapy.

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30

Hinrichs, Karsten, and Timur Shaykhutdinov. "Polarization-Dependent Atomic Force Microscopy–Infrared Spectroscopy (AFM-IR): Infrared Nanopolarimetric Analysis of Structure and Anisotropy of Thin Films and Surfaces." Applied Spectroscopy 72, no. 6 (April 13, 2018): 817–32. http://dx.doi.org/10.1177/0003702818763604.

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Infrared techniques enable nondestructive and label-free studies of thin films with high chemical and structural contrast. In this work, we review recent progress and perspectives in the nanoscale analysis of anisotropic materials using an extended version of the atomic force microscopy–infrared (AFM-IR) technique. This advanced photothermal technique, includes polarization control of the incoming light and bridges the gap in IR spectroscopic analysis of local anisotropic material properties. Such local anisotropy occurs in a wide range of materials during molecular nucleation, aggregation, and crystallization processes. However, analysis of the anisotropy in morphology and structure can be experimentally and theoretically demanding as it is related to order and disorder processes in ranges from nanoscopic to macroscopic length scales, depending on preparation and environmental conditions. In this context IR techniques can significantly assist as IR spectra can be interpreted in the framework of optical models and numerical calculations with respect to both, the present chemical conditions as well as the micro- and nanostructure. With these extraordinary analytic possibilities, the advanced AFM-IR approach is an essential puzzle piece in direction to connect nanoscale and macroscale anisotropic thin film properties experimentally. In this review, we highlight the analytic possibilities of AFM-IR for studies on nanoscale anisotropy with a set of examples for polymer, plasmonic, and polaritonic films, as well as aggregates of large molecules and proteins.

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31

Aleshire, Kyle, Ilia M. Pavlovetc, Robyn Collette, Xiang-Tian Kong, Philip D. Rack, Shubin Zhang, David J. Masiello, Jon P. Camden, Gregory V. Hartland, and Masaru Kuno. "Far-field midinfrared superresolution imaging and spectroscopy of single high aspect ratio gold nanowires." Proceedings of the National Academy of Sciences 117, no. 5 (January 21, 2020): 2288–93. http://dx.doi.org/10.1073/pnas.1916433117.

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Limited approaches exist for imaging and recording spectra of individual nanostructures in the midinfrared region. Here we use infrared photothermal heterodyne imaging (IR-PHI) to interrogate single, high aspect ratio Au nanowires (NWs). Spectra recorded between 2,800 and 4,000 cm−1 for 2.5–3.9-μm-long NWs reveal a series of resonances due to the Fabry–Pérot modes of the NWs. Crucially, IR-PHI images show structure that reflects the spatial distribution of the NW absorption, and allow the resonances to be assigned to the m = 3 and m = 4 Fabry–Pérot modes. This far-field optical measurement has been used to image the mode structure of plasmon resonances in metal nanostructures, and is made possible by the superresolution capabilities of IR-PHI. The linewidths in the NW spectra range from 35 to 75 meV and, in several cases, are significantly below the limiting values predicted by the bulk Au Drude damping parameter. These linewidths imply long dephasing times, and are attributed to reduction in both radiation damping and resistive heating effects in the NWs. Compared to previous imaging studies of NW Fabry–Pérot modes using electron microscopy or near-field optical scanning techniques, IR-PHI experiments are performed under ambient conditions, enabling detailed studies of how the environment affects mid-IR plasmons.

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32

Smith, Matthew J., and Richard A. Palmer. "The Reverse Mirage Effect: Catching the Thermal Wave at the Solid/Liquid Interface." Applied Spectroscopy 41, no. 7 (September 1987): 1106–13. http://dx.doi.org/10.1366/0003702874447437.

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Detection of species at the solid/liquid interface using infrared spectroscopy is severely limited by the opacity of most liquids to the infrared beam. In this work we use a variant of the photothermal beam deflection (“mirage effect”) method to avoid this problem. With this variant of the method (the “reverse mirage effect”), the IR beam passes through a transparent solid first, and then is absorbed by a liquid medium or by chromophoric species at the solid/liquid interface. The probe laser beam grazes the nonilluminated (back) surface of the solid and is deflected by the thermal gradient in the liquid. Results are presented that were obtained with the use of the reverse mirage technique with single-crystal silicon as the transparent solid and the use of pure acetonitrile as the absorbing sample and beam deflection medium. Studies of the position of the laser probe beam center with respect to the Si/CH3CN interface reveal interesting qualities about photothermal detection within the absorbing medium. The resulting spectra are analyzed in terms of the Rosencwaig-Gersho model.

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33

Lekkas, Ioannis, Mark D. Frogley, Timon Achtnich, and Gianfelice Cinque. "Rapidly frequency-tuneable, in-vacuum, and magnetic levitation chopper for fast modulation of infrared light." Review of Scientific Instruments 93, no. 8 (August 1, 2022): 085105. http://dx.doi.org/10.1063/5.0097279.

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We present an in-vacuum mechanical chopper running at high speed and integrated into a magnetic levitating motor for modulating optical beams up to 200 kHz. The compact chopper rotor allows fast acceleration (10 kHz s−1 as standard) for rapid tuning of the modulation frequency, while 1 mm diameter slots provide high optical throughput for larger infrared beams. The modulation performances are assessed using a reference visible laser and the high brightness, broadband, infrared (IR) beam of synchrotron radiation at the MIRIAM beamline B22 at Diamond Light Source, UK. For our application of IR nanospectroscopy, minimizing the temporal jitter on the modulated beam due to chopper manufacturing and control tolerances is essential to limit the noise level in measurements via lock-in detection, while high modulation frequencies are needed to achieve high spatial resolution in photothermal nanospectroscopy. When reaching the maximum chopping frequency of 200 kHz, the jitter was found to be 0.9% peak-to-peak. The described chopper now replaces the standard ball-bearing chopper in our synchrotron-based FTIR photothermal nanospectroscopy system, and we demonstrate improved spectroscopy results on a 200 nm thickness polymer film.

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Calvagna, Chiara, Andrea Azelio Mencaglia, Iacopo Osticioli, Daniele Ciofini, and Salvatore Siano. "Novel Probe for Thermally Controlled Raman Spectroscopy Using Online IR Sensing and Emissivity Measurements." Sensors 22, no. 7 (March 31, 2022): 2680. http://dx.doi.org/10.3390/s22072680.

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Temperature rise during Raman spectroscopy can induce chemical alterations of the material under analysis and seriously affect its characterization. Thus, such photothermal side effects can represent a serious problem to be carefully controlled in order to safeguard the integrity of the material and its spectral features. In this work, an innovative probe for thermally controlled portable Raman spectroscopy (exc. 785 nm) equipped with infrared sensing lines was developed. It included an infrared source and two thermopile sensors, which allowed to perform real-time measurements of the local emissivity of the material surface under laser excitation. The emissivity, which is needed in order to monitor the temperature of the irradiated surface through infrared radiation measurements, represents the complementary component of the reflectance in the radiative energy balance. Thus, total reflectance, temperature measurements and Raman spectroscopy were integrated in the present probe. After independently assessing the reliability of the former in order to derive the emissivity of variety of materials, the probe was successfully applied on pigments, paint layers, and a painting on canvas. The results achieved evidence the significant exploitation potential of the novel tool.

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Bakir, Gorkem, Benoit E. Girouard, Richard Wiens, Stefan Mastel, Eoghan Dillon, Mustafa Kansiz, and Kathleen M. Gough. "Orientation Matters: Polarization Dependent IR Spectroscopy of Collagen from Intact Tendon Down to the Single Fibril Level." Molecules 25, no. 18 (September 19, 2020): 4295. http://dx.doi.org/10.3390/molecules25184295.

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Infrared (IR) spectroscopy has been used for decades to study collagen in mammalian tissues. While many changes in the spectral profiles appear under polarized IR light, the absorption bands are naturally broad because of tissue heterogeneity. A better understanding of the spectra of ordered collagen will aid in the evaluation of disorder in damaged collagen and in scar tissue. To that end, collagen spectra have been acquired with polarized far-field (FF) Fourier Transform Infrared (FTIR) imaging with a Focal Plane Array detector, with the relatively new method of FF optical photothermal IR (O-PTIR), and with nano-FTIR spectroscopy based on scattering-type scanning near-field optical microscopy (s-SNOM). The FF methods were applied to sections of intact tendon with fibers aligned parallel and perpendicular to the polarized light. The O-PTIR and nano-FTIR methods were applied to individual fibrils of 100–500 nm diameter, yielding the first confirmatory and complementary results on a biopolymer. We observed that the Amide I and II bands from the fibrils were narrower than those from the intact tendon, and that both relative intensities and band shapes were altered. These spectra represent reliable profiles for normal collagen type I fibrils of this dimension, under polarized IR light, and can serve as a benchmark for the study of collagenous tissues.

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Khan, Ziaul Raza, Anver Aziz, Mohd Shahid Khan, and M. U. Khandaker. "Influence of zinc concentration on band gap and sub-band gap absorption on ZnO nanocrystalline thin films sol-gel grown." Materials Science-Poland 35, no. 1 (February 24, 2017): 246–53. http://dx.doi.org/10.1515/msp-2017-0039.

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AbstractZnO thin films were fabricated on quartz substrates at different zinc acetate molar concentrations using sol-gel spin coating method. The samples were characterized using X-ray diffraction, field emission scanning electron microscope, UV-Vis spectroscopy, FT-IR spectroscopy and photoluminescence spectroscopy. Sub-band gap absorption of ZnO thin films in the forbidden energy region was carried out using highly sensitive photothermal deflection spectroscopy (PDS). The absorption coefficients of ZnO thin films increased in the range of 1.5 eV to 3.0 eV, upon increasing zinc concentration. The optical band gaps were evaluated using Tauc’s plots and found to be in the range of 3.31 eV to 3.18 eV. They showed the red shift in the band edge on increase in zinc concentration. The PL spectra of ZnO thin films revealed the characteristic band edge emission centered at the 396 nm along with green emission centered at the 521 nm.

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37

dos Santos, A. Catarina V. D., Bernhard Lendl, and Georg Ramer. "Systematic analysis and nanoscale chemical imaging of polymers using photothermal-induced resonance (AFM-IR) infrared spectroscopy." Polymer Testing 106 (February 2022): 107443. http://dx.doi.org/10.1016/j.polymertesting.2021.107443.

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38

Salazar Sandoval, Sebastián, Elizabeth Cortés-Adasme, Eduardo Gallardo-Toledo, Ingrid Araya, Freddy Celis, Nicolás Yutronic, Paul Jara та Marcelo J. Kogan. "β-Cyclodextrin-Based Nanosponges Inclusion Compounds Associated with Gold Nanorods for Potential NIR-II Drug Delivery". Pharmaceutics 14, № 10 (17 жовтня 2022): 2206. http://dx.doi.org/10.3390/pharmaceutics14102206.

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This article describes the synthesis and characterization of two nanocarriers consisting of β-cyclodextrin-based nanosponges (NSs) inclusion compounds (ICs) and gold nanorods (AuNRs) for potential near-infrared II (NIR-II) drug-delivery systems. These nanosystems sought to improve the stability of two drugs, namely melphalan (MPH) and curcumin (CUR), and to trigger their photothermal release after a laser irradiation stimulus (1064 nm). The inclusion of MPH and CUR inside each NS was confirmed by field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, Fourier transform infrared spectroscopy, (FT-IR) differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and proton nuclear magnetic resonance (1H-NMR). Furthermore, the association of AuNRs with both ICs was confirmed by FE-SEM, energy-dispersive spectroscopy (EDS), TEM, dynamic light scattering (DLS), ζ-potential, and UV–Vis. Moreover, the irradiation assays demonstrated the feasibility of the controlled-photothermal drug release of both MPH and CUR in the second biological window (1000–1300 nm). Finally, MTS assays depicted that the inclusion of MPH and CUR inside the cavities of NSs reduces the effects on mitochondrial activity, as compared to that observed in the free drugs. Overall, these results suggest the use of NSs associated with AuNRs as a potential technology of controlled drug delivery in tumor therapy, since they are efficient and non-toxic materials.

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Shen, Jun, Andreas Mandelis, Andreas Othonos, and Joseph Vanniasinkam. "High-Resolution Quadrature Photopyroelectric Spectroscopy of a-Si:H Thin Films Deposited on Silicon Wafers." Applied Spectroscopy 49, no. 6 (June 1995): 819–24. http://dx.doi.org/10.1366/0003702953964624.

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The recently developed photothermal technique of quadrature photopyroelectric spectroscopy (Q-PPES) has been applied to measurements of amorphous Si thin films deposited on crystalline Si substrates. Direct, meaningful comparisons have been made between purely optical transmission in-phase (IP-PPES) spectra, and purely thermal-wave sub-gap spectra with the use of a novel noncontacting PPES instrument to record lock-in in-phase and quadrature spectra, respectively. FT-IR transmission spectra have also been obtained for a comparison with this IP-PPES optical method. The results of the present work showed that the FT-IR method performs the worst in terms of spectral resolution of thin films and sub-bandgap defect/impurity absorptions inherent in the Si wafer substrate. The optical IP-PPES channel, however, albeit more sensitive than the FT-IR technique, fails to resolve spectra from surface films thinner than 2100 Å, but is sensitive to sub-bandgap absorptions. The thermal-wave Q-PPES channel is capable of resolving thin-film spectra well below 500 Å thick and exhibits strong signal levels from the crystalline Si sub-bandgap absorptions. Depending on the surface thin-film orientation toward, or away from, the direction of the incident radiation, the estimated minimum mean film thickness resolvable spectroscopically by Q-PPES is either 40 Å or 100 Å, respectively.

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40

Bauer, Alexander, Otto Hertzberg, Arne Küderle, Dominik Strobel, Miguel A. Pleitez, and Werner Mäntele. "IR-spectroscopy of skin in vivo : Optimal skin sites and properties for non-invasive glucose measurement by photoacoustic and photothermal spectroscopy." Journal of Biophotonics 11, no. 1 (April 18, 2017): e201600261. http://dx.doi.org/10.1002/jbio.201600261.

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41

Kim, Dasom, Reeju Amatya, Seungmi Hwang, Sumi Lee, Kyoung Ah Min, and Meong Cheol Shin. "BSA-Silver Nanoparticles: A Potential Multimodal Therapeutics for Conventional and Photothermal Treatment of Skin Cancer." Pharmaceutics 13, no. 4 (April 17, 2021): 575. http://dx.doi.org/10.3390/pharmaceutics13040575.

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Silver nanoparticles (NPs) have attracted a considerable interest in the field of cancer research due to their potential utility in cancer therapy. In the present study, we developed bovine serum albumin (BSA)-coated silver NPs (BSA-Silver NPs) and characterized in vitro multimodal therapeutic activities of NPs for the treatment of skin cancer. BSA-Silver NPs were synthesized by a single-step reduction process, and the successful preparation was verified through a list of physical characterizations, including transmission electron microscopy (TEM), ultraviolet-visible (UV–VIS) light spectroscopy, dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy. The synthesized BSA-Silver NPs showed marked cytocidal effects on B16F10 melanoma cells, which was likely caused by oxidative stress. BSA-Silver NPs also elicited significant anti-angiogenic effects on HUVEC (human umbilical vein endothelial cell) by inhibiting their proliferation, migration, and tube formation. Moreover, BSA-Silver NPs showed a considerable light-to-heat conversion ability, suggesting their utility as photothermal agents. Overall, our findings suggest that BSA-Silver NPs may be promising candidates for the multimodal therapy of skin cancer.

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Quaroni, Luca. "Characterization of Intact Eukaryotic Cells with Subcellular Spatial Resolution by Photothermal-Induced Resonance Infrared Spectroscopy and Imaging." Molecules 24, no. 24 (December 9, 2019): 4504. http://dx.doi.org/10.3390/molecules24244504.

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Photothermal-induced resonance (PTIR) spectroscopy and imaging with infrared light has seen increasing application in the molecular spectroscopy of biological samples. The appeal of the technique lies in its capability to provide information about IR light absorption at a spatial resolution better than that allowed by light diffraction, typically below 100 nm. In the present work, we tested the capability of the technique to perform measurements with subcellular resolution on intact eukaryotic cells, without drying or fixing. We demonstrate the possibility of obtaining PTIR images and spectra from the nucleus and multiple organelles with high resolution, better than that allowed by diffraction with infrared light. We obtain particularly strong signal from bands typically assigned to acyl lipids and proteins. We also show that while a stronger signal is obtained from some subcellular structures, other large subcellular components provide a weaker or undetectable PTIR response. The mechanism that underlies such variability in response is presently unclear. We propose and discuss different possibilities, addressing thermomechanical, geometrical, and electrical properties of the sample and the presence of cellular water, from which the difference in response may arise.

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43

Jo, Gayoung, Eun Jeong Kim, and Hoon Hyun. "Enhanced Tumor Uptake and Retention of Cyanine Dye–Albumin Complex for Tumor-Targeted Imaging and Phototherapy." International Journal of Molecular Sciences 24, no. 1 (January 3, 2023): 862. http://dx.doi.org/10.3390/ijms24010862.

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Heptamethine cyanine dyes are widely used for in vivo near-infrared (NIR) fluorescence imaging and NIR laser-induced cancer phototherapy due to their good optical properties. Since most of heptamethine cyanine dyes available commercially are highly hydrophobic, they can usually be used for in vivo applications after formation of complexes with blood plasma proteins, especially serum albumin, to increase aqueous solubility. The complex formation between cyanine dyes and albumin improves the chemical stability and optical property of the hydrophobic cyanine dyes, which is the bottom of their practical use. In this study, the complexes between three different heptamethine cyanine dyes, namely clinically available indocyanine green (ICG), commercially available IR-786 and zwitterionic ZW800-Cl, and bovine serum albumin (BSA), were prepared to explore the effect of cyanine dyes on their tumor uptake and retention. Among the three complexes, IR-786©BSA exhibited increased tumor accumulation with prolonged tumor retention, compared to other complexes. Moreover, IR-786 bound to BSA played an important role in tumor growth suppression due to its cytotoxicity. To achieve complete tumor ablation, the tumor targeted by IR-786©BSA was further exposed to 808 nm laser irradiation for effective photothermal cancer treatment.

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Bulmahn, Julia C., Gleb Tikhonowski, Anton A. Popov, Andrey Kuzmin, Sergey M. Klimentov, Andrei V. Kabashin, and Paras N. Prasad. "Laser-Ablative Synthesis of Stable Aqueous Solutions of Elemental Bismuth Nanoparticles for Multimodal Theranostic Applications." Nanomaterials 10, no. 8 (July 26, 2020): 1463. http://dx.doi.org/10.3390/nano10081463.

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Elemental bismuth (Bi) nanoparticles (NPs), with the high atomic density of the Bi nuclei, could serve as efficient targeted agents for cancer treatment, with applications such as contrast agents for computed tomography (CT) imaging, sensitizers for image-guided X-ray radiotherapy, and photothermal therapy. However, the synthesis of elemental Bi NPs suitable for biological applications is difficult using conventional chemical routes. Here, we explore the fabrication of ultrapure Bi-based nanomaterials by femtosecond laser ablation from a solid Bi target in ambient liquids and characterize them by a variety of techniques, including TEM, SEM, XRD, FTIR, Raman, and optical spectroscopy. We found that laser-ablative synthesis using an elemental Bi solid target leads to the formation of spherical Bi NPs having the mean size of 20–50 nm and a low size-dispersion. The NPs prepared in water experience a fast (within a few minutes) conversion into 400–500 nm flake-like nanosheets, composed of bismuth subcarbonates, (BiO)2CO3 and (BiO)4CO3(OH)2, while the NPs prepared in acetone demonstrate high elemental stability. We introduce a procedure to obtain a stable aqueous solution of elemental Bi NPs suitable for biological applications, based on the coating of Bi NPs prepared in acetone with Pluronic® F68 and their subsequent transfer to water. We also show that the laser-synthesized elemental Bi NPs, due to their vanishing band gap, exhibit remarkable absorption in the infrared range, which can be used for the activation of photothermal therapy in the near IR-to-IR window with maximum optical transparency in biological media. Exempt of any toxic synthetic by-products, laser-ablated elemental Bi NPs present a novel appealing nanoplatform for combination image-guided photoradiotherapies.

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45

Bazin, Dominique, Elise Bouderlique, Ellie Tang, Michel Daudon, Jean-Philippe Haymann, Vincent Frochot, Emmanuel Letavernier, et al. "Using mid infrared to perform investigations beyond the diffraction limits of microcristalline pathologies: advantages and limitation of Optical PhotoThermal IR spectroscopy." Comptes Rendus. Chimie 25, S1 (July 27, 2022): 1–27. http://dx.doi.org/10.5802/crchim.196.

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46

Bouderlique, Elise, Ellie Tang, Jeremy Zaworski, Amélie Coudert, Dominique Bazin, Ferenc Borondics, Jean-Philippe Haymann, et al. "Vitamin D and Calcium Supplementation Accelerate Vascular Calcification in a Model of Pseudoxanthoma Elasticum." International Journal of Molecular Sciences 23, no. 4 (February 19, 2022): 2302. http://dx.doi.org/10.3390/ijms23042302.

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Arterial calcification is a common feature of pseudoxanthoma elasticum (PXE), a disease characterized by ABCC6 mutations, inducing a deficiency in pyrophosphate, a key inhibitor of calcium phosphate crystallization in arteries. Methods: we analyzed whether long-term exposure of Abcc6−/− mice (a murine model of PXE) to a mild vitamin D supplementation, with or without calcium, would impact the development of vascular calcification. Eight groups of mice (including Abcc6−/− and wild-type) received vitamin D supplementation every 2 weeks, a calcium-enriched diet alone (calcium in drinking water), both vitamin D supplementation and calcium-enriched diet, or a standard diet (controls) for 6 months. Aorta and kidney artery calcification was assessed by 3D-micro-computed tomography, Optical PhotoThermal IR (OPTIR) spectroscopy, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) and Yasue staining. Results: at 6 months, although vitamin D and/or calcium did not significantly increase serum calcium levels, vitamin D and calcium supplementation significantly worsened aorta and renal artery calcification in Abcc6−/− mice. Conclusions: vitamin D and/or calcium supplementation accelerate vascular calcification in a murine model of PXE. These results sound a warning regarding the use of these supplementations in PXE patients and, to a larger extent, patients with low systemic pyrophosphate levels.

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Zhao, Yaoli, Patatri Chakraborty, Vaishali Maheshkar, Karthik Dantu, Nicholas Stavinski, Luis Velarde, and Thomas Thundat. "Multi-Modal Stand-Off Detection of Plastics for Sorting Application." ECS Meeting Abstracts MA2022-02, no. 61 (October 9, 2022): 2254. http://dx.doi.org/10.1149/ma2022-02612254mtgabs.

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Plastics are extremely valuable to our society and are widely used in many industries such as food, beverage, textile, healthcare, automotive, aerospace, construction, agriculture, oil, etc. Since plastics do not degrade easily with time, the discarded plastics pose a grave environmental problem. Only less than 10% of plastics is recycled in the US. Therefore, there is an urgent need to increase the recycling of plastic products. At present, sorting of plastic waste is carried out manually which is time consuming, costly and manual labor intensive. To address this problem, a novel multi-modal sensor platform capable of improving the accuracy of automated sorting of various plastics by using molecular identification has been developed. This multimodal technique of standoff photothermal-photoacoustic detection is a combination of mid-infrared (MIR) photo-thermal spectroscopy and photoacoustic spectroscopy for characterizing surfaces. Since MIR is free of overtones, this region is known as the molecular fingerprint region. In this technique, the plastic surface is illuminated with a pulsed laser beam from a tunable quantum cascade laser (QCL). The photothermal detection is accomplished by collecting the scattered light from the plastic surface which contains the molecular vibration spectrum of the sample. A silicon bi-material microcantilever, fabricated by depositing a thin metal film on one of its sides is used as a sensitive uncooled infrared detector. Monitoring the bi-material cantilever bending as a function of illumination wavelength provides the IR absorption spectrum of the plastic material. Simultaneously, the photoacoustic signal generated by the absorption of light is monitored by a sensitive microphone. A highly sensitive microfabricated acoustic resonator is used for collecting the photoacoustic signal. Monitoring the microphone response as a function of wavelength produces photoacoustic spectrum (PAS) of the sample. This non-destructive characterization technique will help in enhancing the quality of plastic sorting process at materials recovery facilities and other industries by making the process inexpensive and time efficient.

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Saikova, Svetlana, Alexander Pavlikov, Tatyana Trofimova, Yuri Mikhlin, Denis Karpov, Anastasiya Asanova, Yuri Grigoriev, et al. "Hybrid Nanoparticles Based on Cobalt Ferrite and Gold: Preparation and Characterization." Metals 11, no. 5 (April 25, 2021): 705. http://dx.doi.org/10.3390/met11050705.

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During the past few decades, hybrid nanoparticles (HNPs) based on a magnetic material and gold have attracted interest for applications in catalysis, diagnostics and nanomedicine. In this paper, magnetic CoFe2O4/Au HNPs with an average particle size of 20 nm, decorated with 2 nm gold clusters, were prepared using methionine as a reducer and an anchor between CoFe2O4 and gold. The methionine was used to grow the Au clusters to a solid gold shell (up to 10 gold deposition cycles). The obtained nanoparticles (NPs) were studied by X-Ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, X-Ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy techniques. The TEM images of the obtained HNPs showed that the surface of cobalt ferrite was covered with gold nanoclusters, the size of which slightly increased with an increase in the number of gold deposition cycles (from 2.12 ± 0.15 nm after 1 cycle to 2.46 ± 0.13 nm after 10 cycles). The density of the Au clusters on the cobalt ferrite surface insignificantly decreased during repeated stages of gold deposition: 21.4 ± 2.7 Au NPs/CoFe2O4 NP after 1 cycle, 19.0 ± 1.2 after 6 cycles and 18.0 ± 1.4 after 10 cycles. The magnetic measurements showed that the obtained HNPs possessed typical ferrimagnetic behavior, which corresponds to that of CoFe2O4 nanoparticles. The toxicity evaluation of the synthesized HNPs on Chlorella vulgaris indicated that they can be applied to biomedical applications such as magnetic hyperthermia, photothermal therapy, drug delivery, bioimaging and biosensing.

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Lin, Yen-Ting, Hongtu He, Huseyin Kaya, Hongshen Liu, Dien Ngo, Nicholas J. Smith, Joy Banerjee, Ali Borhan, and Seong H. Kim. "Photothermal Atomic Force Microscopy Coupled with Infrared Spectroscopy (AFM-IR) Analysis of High Extinction Coefficient Materials: A Case Study with Silica and Silicate Glasses." Analytical Chemistry 94, no. 13 (March 21, 2022): 5231–39. http://dx.doi.org/10.1021/acs.analchem.1c04398.

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Marcott, Curtis, Mustafa Kansiz, Eoghan Dillon, Debra Cook, Michael N. Mang, and Isao Noda. "Two-dimensional correlation analysis of highly spatially resolved simultaneous IR and Raman spectral imaging of bioplastics composite using optical photothermal Infrared and Raman spectroscopy." Journal of Molecular Structure 1210 (June 2020): 128045. http://dx.doi.org/10.1016/j.molstruc.2020.128045.

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