Artem Pliss | SUNY: University at Buffalo (original) (raw)

Papers by Artem Pliss

Research paper thumbnail of Fluorescence lifetime imaging and its applications in cellular microenvironment measurement and auxiliary diagnosis

We present our recent work on the applications of fluorescence lifetime imaging microscopy(FLIM),... more We present our recent work on the applications of fluorescence lifetime imaging microscopy(FLIM), including the monitoring of macromolecule dynamic changes in the nucleolar compartments and the auxiliary diagnosis of H and E-stained sections. We demonstrated the capability of FLIM to measure protein concentration in the specific cellular compartments in live cells. We proposed to use FLIM to monitor changes in intracellular protein concentration caused by various factors e.g. cell cycle progression, drug treatment etc. In the future, FLIM technology is expected to be combined with super-resolution optical imaging. FLIM with molecular resolution will have the potential to serve as a powerful tool for discovering new phenomena and revealing new mechanisms in biomedical research, which will effectively promote the development of life science.

Research paper thumbnail of A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction

CNS Neuroscience & Therapeutics, Jul 11, 2019

A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacun... more A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction. CNS

Research paper thumbnail of Mitochondrial Dysfunction and Apoptosis in Brain Microvascular Endothelial Cells Following Blast Traumatic Brain Injury

Cellular and Molecular Neurobiology

Research paper thumbnail of Convergent Science with Laser Raman Spectroscopy for Biophotonics

Advances in Optics and Photonics, Feb 16, 2023

Research paper thumbnail of Decoupled Rare-Earth Nanoparticles for On-Demand Upconversion Photodynamic Therapy and High-Contrast Near Infrared Imaging in NIR IIb

ACS Applied Bio Materials

Research paper thumbnail of A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction

CNS Neuroscience & Therapeutics, 2019

A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacun... more A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction. CNS

Research paper thumbnail of Near-Infrared Irradiation Affects Lipid Metabolism in Neuronal Cells, Inducing Lipid Droplets Formation

ACS Chemical Neuroscience, 2018

It is known that lipids play an outstanding role in cellular regulation and their dysfunction has... more It is known that lipids play an outstanding role in cellular regulation and their dysfunction has been linked to many diseases. Thus, modulation of lipid metabolism may provide new pathways for disease treatment or prevention. In this work, near infrared (NIR) light was applied to modulate lipid metabolism, and increase intracellular lipid content in rat cortical neurons (RCN). Using label-free CARS microscopy, we have monitored the intracellular lipid content in RCN at a single cell level. A major increase in average level of lipid per cell after treatment with laser diode at 808 nm was found, nonlinearly dependent on the irradiation dose. Moreover, a striking formation of lipid droplets (LDs) in the irradiated RCN was discovered. Further experiments and analysis reveal a strong correlation between NIR light induced generation of reactive oxygen species (ROS), lipids level and LDs formation in RCN. Our findings can contribute to a development of therapeutic approaches for neurological disorders via NIR light control of lipid metabolism in neuronal cells.

Research paper thumbnail of Onset of triplet-state spectral diffusion in the presence of both orientational and substitutional disorders: binary solid solutions of 1-bromo-4-chloronaphthalene and 1,4-dibromonaphthalene

The Journal of Physical Chemistry, 1985

The spectral diffusion in the presence of both orientational and substitutional disorders is inve... more The spectral diffusion in the presence of both orientational and substitutional disorders is investigated at 4.2 and 1.8 K. Our systems of study are different compmitions of solid solutions of 1-bromd-chloronaphthalene (BCN) and 1 &dibromonaphthalene (DBN). BCN is known to form an orientationally disordered solid. We used a wide range of concentrations within which the DBN crystal structure prevails. The phosphorescence of BCN was monitored as a function of the concentration of BCN. The analysis of our results shows that (i) the spectral diffusion is concentration dependent and, at very low concentration, the excitation is completely localized; (ii) as the concentration of BCN is increased, the onset of spectral diffusion is observed; (iii) above a critical concentration, the spectral diffusion rate increases rapidly; (iv) the process of spectral diffusion is highly temperature dependent. The concentration dependence behavior is found to be consistent with both the diffusion and the percolation models. From the analysis of the results, we conclude that the spectral diffusion in this system is phonon assisted and it involves cascading down in steps from higher to lower energy sites. Also, the theoretical analysis suggests that the excitation transport topology involves 2-dimensional exchange interactions.

Research paper thumbnail of Electrooptic effect in Langmuir-Blodgett films of 2-(docosylamino)-5-nitropyridine probed by surface plasmon waves

Langmuir, 1992

Measurements of electrooptic modulation of surface plasmon resonance have been carried out on hor... more Measurements of electrooptic modulation of surface plasmon resonance have been carried out on horizontally transferred Langmuir-Blodgett films of 2-(docosylamino)-5-nitropyridine. The observed Pockels response is approximately constant for different numbers of layers in multilayered films and is proportional to the strength of the modulating field. The calculated second-order susceptibility values are-2 x 10-13 m V 1 , 2 orders of magnitude lower than those derived from second harmonic generation studies. The presence of the Pockels effect is attributed to off-diagonal terms in the second-order susceptibility.

Research paper thumbnail of Research on nonlinear optical materials: an assessment

Research paper thumbnail of A Single-Organelle Optical Omics Platform for Cell Science and Biomarker Discovery

Research in fundamental cell biology and pathology could be revolutionized by developing the capa... more Research in fundamental cell biology and pathology could be revolutionized by developing the capacity for quantitative molecular analysis of subcellular structures. To that end, we introduce the Ramanomics platform, based on confocal Raman microspectrometry coupled to a biomolecular component analysis algorithm, which together enable us to molecularly profile single organelles in a live-cell environment. This emerging omics approach categorizes the entire molecular makeup of a sample into about a dozen of general classes and subclasses of biomolecules and quantifies their amounts in submicrometer volumes. A major contribution of our study is an attempt to bridge Raman spectrometry with big-data analysis in order to identify complex patterns of biomolecules in a single cellular organelle and leverage discovery of disease biomarkers. Our data reveal significant variations in organellar composition between different cell lines. We also demonstrate the merits of Ramanomics for identifying diseased cells by using prostate cancer as an example. We report large-scale molecular transformations in the mitochondria, Golgi apparatus, and endoplasmic reticulum that accompany the development of prostate cancer. Based on these findings, we propose that Ramanomics datasets in distinct organelles constitute signatures of cellular metabolism in healthy and diseased states.

Research paper thumbnail of Fluorescence lifetime imaging and its applications in cellular microenvironment measurement and auxiliary diagnosis

International Conference on Photonics and Imaging in Biology and Medicine, 2017

Research paper thumbnail of Small molecule based EGFR targeting of biodegradable nanoparticles containing temozolomide and Cy5 dye for greatly enhanced image-guided glioblastoma therapy

Nanomedicine: Nanotechnology, Biology and Medicine, 2021

Current glioblastoma multiform (GBM) treatment is insufficient, facing obstacles like poor tumor ... more Current glioblastoma multiform (GBM) treatment is insufficient, facing obstacles like poor tumor accumulation and dose limiting side effects of chemotherapeutic agents. Targeted nanomaterials offer breakthrough potential in GBM treatment; however, traditional antibody-based targeting poses challenges for live brain application. To overcome current obstacles, we introduce here the development of a small molecule targeting agent, CFMQ, coupled to biocompatible chitosan coated poly(lactic-co-glycolic) acid nanoparticles. These targeted nanoparticles enhance cellular uptake and show rapid blood-brain barrier (BBB) permeability in-vitro, demonstrating the ability to effectively deliver their load to tumor cells. Encapsulation of the chemotherapeutic agent, temozolomide (TMZ), decreases the IC50~34-fold compared to free-drug. Also, CFMQ synergistically suppresses tumor cell progression, reducing colony formation (98%), cell migration (84%), and cell invasion (77%). Co-encapsulation of Cy5 enables optical image guided therapy. This biocompatible theranostic nanoformulation shows early promise in significantly enhancing the efficacy of TMZ, while providing potential for image-guided therapy for GBM.

Research paper thumbnail of Laser-ablative synthesis of aggregation-induced enhanced emission luminophore dyes in aqueous solutions

Synthesis and Photonics of Nanoscale Materials XVI, 2019

Methods of femtosecond laser ablation in deionized water were used to fabricate ultrasmall (< ... more Methods of femtosecond laser ablation in deionized water were used to fabricate ultrasmall (< 2 nm), bare (ligand-free) organic luminophore DCEtDCS nanoparticles, which exhibit aggregation enhanced emission in the green range (533 nm) with the quantum yield exceeding 58% and provide no concentration quenching. In contrast to chemically synthesized counterparts, laser-synthesized DCEtDCS nanoparticles do not contain any organic impurities due to their preparation in aqueous medium and do not require surfactants to stabilize colloidal solutions, which makes them highly suitable for intracellular uptake and bioimaging. The highly negative surface charge of these nanoparticles impeded their cellular uptake, but when the surface was coated with chitosan, a cationic polymer, intracellular uptake in microglia was achieved. Using in vitro model, we finally demonstrate the efficient employment of ultrasmall and surfactant free fluorescent organic nanoparticles prepared by laser ablation as markers in bioimaging.

Research paper thumbnail of Organic Solvent and Surfactant Free Fluorescent Organic Nanoparticles by Laser Ablation of Aggregation‐Induced Enhanced Emission Dyes

Advanced Optical Materials, 2018

Less toxic and highly fluorescent nanoparticles are in high demand to image biological events and... more Less toxic and highly fluorescent nanoparticles are in high demand to image biological events and early-stage disease. We present a strategy to fabricate highly fluorescent organic nanoparticles by laser ablation of aggregation induced enhanced emission (AIE) luminophores, which are free of any organic solvent and surfactant. As these dyes

Research paper thumbnail of Synergic treatment of Alzheimer’s disease with brain targeted nanoparticles incorporating NgR-siRNA and brain derived neurotrophic factor

Smart Materials in Medicine, 2020

treatment of Alzheimer's disease with brain targeted nanoparticles incorporating NgR-siRNA and br... more treatment of Alzheimer's disease with brain targeted nanoparticles incorporating NgR-siRNA and brain derived neurotrophic factor, Smart Materials in Medicine,

Research paper thumbnail of Inside Cover: Cellular transformations in near‐infrared light‐induced apoptosis in cancer cells revealed by label‐free CARS imaging (J. Biophotonics 12/2019)

Journal of Biophotonics, 2019

Research paper thumbnail of ICG‐Sensitized NaYF 4 :Er Nanostructure for Theranostics

Advanced Optical Materials, 2018

played a substantial role in biomedical imaging. [1-3] These dielectric nanocrystals, doped with ... more played a substantial role in biomedical imaging. [1-3] These dielectric nanocrystals, doped with rare-earth ions, have generated significant interest as "nanovectors" with multiple capabilities such as biosensing, luminescent imaging, drug delivery, and theranostics. [4-14] Multimodal functionality is especially important in applications of nanoagents for therapeutic purposes, when the monitoring of a therapeutic process in real time is necessary for the treatment evaluation. Fluoride nanocrystals, doped with trivalent Erbium ions, are one of the most basic nanomaterials used in optical bioimaging. [1,2,15] This nanophosphor produces upconverted emission in the visible (≈540 and ≈650 nm) and Stokes-shift emission in the NIR wavelength range (≈1520 and ≈2800 nm) under NIR excitation at ≈808 nm. Emission centered at 1520 nm is in the second optical transparency window in the NIR range (NIR-II) and, therefore, can be used for bioimaging due to lower absorption and scattering by bioconstituents, compared to the visible light. [16] Despite the considerable capability of this nanomaterial for applications to bioscience, relatively low absorption by Er 3+ ions at ≈800 nm and low luminescence yield compared to the bulk materials require an optimization of nanoparticle optical parameters. Not always, this task could be performed by an increase in Er 3+ concentration. An optimal concentration of this component is within 1-2 mol% and further increasing Er 3+ concentration results in quenching of luminescence. There are other several strategies to improve the luminescence of nanoparticles. The use of core/shell architecture in the nanoparticles protects the luminescent ions in the core from nonradiative decay caused by surface defects as well as from vibrational deactivation by the environment in colloidal dispersions. [17-19] Employment of a photosensitizer such as Yb 3+ , which efficiently transfers the excitation to Er 3+ , [20-22] can significantly improve the emission intensity of nanomaterial. Surface plasmon enhancement using a coupled metallic nanostructure has also been used. [23-25] In this work, addressing the problem of low absorption of Er 3+-doped LNPs, we report the design and synthesis of indocyanine green (ICG) dye sensitized NaYF 4 :Er LNPs. ICG has strong absorption at 808 nm with large Stokes shifted emission band [6,26,27] that overlaps with the Er 3+ absorption band (Scheme 1), enabling efficient energy transfer from ICG to Er 3+ ions. Our group has recently demonstrated the application of

Research paper thumbnail of Applications of fluorescence lifetime imaging in clinical medicine

Journal of Innovative Optical Health Sciences, 2017

Fluorescence lifetime is not only associated with the molecular structure of fluorophores, but al... more Fluorescence lifetime is not only associated with the molecular structure of fluorophores, but also strongly depends on the environment around them, which allows fluorescence lifetime imaging microscopy (FLIM) to be used as a tool for precise measurement of the cell or tissue microenvironment. This review introduces the basic principle of fluorescence lifetime imaging technology and its application in clinical medicine, including research and diagnosis of diseases in skin, brain, eyes, mouth, bone, blood vessels and cavity organs, and drug evaluation. As a noninvasive, nontoxic and nonionizing radiation technique, FLIM demonstrates excellent performance with high sensitivity and specificity, which allows to determine precise position of the lesion and, thus, has good potential for application in biomedical research and clinical diagnosis.

Research paper thumbnail of Corrigendum: Resonance Raman Probes for Organelle-Specific Labeling in Live Cells

Scientific reports, Sep 2, 2016

Research paper thumbnail of Fluorescence lifetime imaging and its applications in cellular microenvironment measurement and auxiliary diagnosis

We present our recent work on the applications of fluorescence lifetime imaging microscopy(FLIM),... more We present our recent work on the applications of fluorescence lifetime imaging microscopy(FLIM), including the monitoring of macromolecule dynamic changes in the nucleolar compartments and the auxiliary diagnosis of H and E-stained sections. We demonstrated the capability of FLIM to measure protein concentration in the specific cellular compartments in live cells. We proposed to use FLIM to monitor changes in intracellular protein concentration caused by various factors e.g. cell cycle progression, drug treatment etc. In the future, FLIM technology is expected to be combined with super-resolution optical imaging. FLIM with molecular resolution will have the potential to serve as a powerful tool for discovering new phenomena and revealing new mechanisms in biomedical research, which will effectively promote the development of life science.

Research paper thumbnail of A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction

CNS Neuroscience & Therapeutics, Jul 11, 2019

A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacun... more A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction. CNS

Research paper thumbnail of Mitochondrial Dysfunction and Apoptosis in Brain Microvascular Endothelial Cells Following Blast Traumatic Brain Injury

Cellular and Molecular Neurobiology

Research paper thumbnail of Convergent Science with Laser Raman Spectroscopy for Biophotonics

Advances in Optics and Photonics, Feb 16, 2023

Research paper thumbnail of Decoupled Rare-Earth Nanoparticles for On-Demand Upconversion Photodynamic Therapy and High-Contrast Near Infrared Imaging in NIR IIb

ACS Applied Bio Materials

Research paper thumbnail of A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction

CNS Neuroscience & Therapeutics, 2019

A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacun... more A DTI study of leukoaraiosis and the differential diagnosis between leukoaraiosis and acute lacunar infarction. CNS

Research paper thumbnail of Near-Infrared Irradiation Affects Lipid Metabolism in Neuronal Cells, Inducing Lipid Droplets Formation

ACS Chemical Neuroscience, 2018

It is known that lipids play an outstanding role in cellular regulation and their dysfunction has... more It is known that lipids play an outstanding role in cellular regulation and their dysfunction has been linked to many diseases. Thus, modulation of lipid metabolism may provide new pathways for disease treatment or prevention. In this work, near infrared (NIR) light was applied to modulate lipid metabolism, and increase intracellular lipid content in rat cortical neurons (RCN). Using label-free CARS microscopy, we have monitored the intracellular lipid content in RCN at a single cell level. A major increase in average level of lipid per cell after treatment with laser diode at 808 nm was found, nonlinearly dependent on the irradiation dose. Moreover, a striking formation of lipid droplets (LDs) in the irradiated RCN was discovered. Further experiments and analysis reveal a strong correlation between NIR light induced generation of reactive oxygen species (ROS), lipids level and LDs formation in RCN. Our findings can contribute to a development of therapeutic approaches for neurological disorders via NIR light control of lipid metabolism in neuronal cells.

Research paper thumbnail of Onset of triplet-state spectral diffusion in the presence of both orientational and substitutional disorders: binary solid solutions of 1-bromo-4-chloronaphthalene and 1,4-dibromonaphthalene

The Journal of Physical Chemistry, 1985

The spectral diffusion in the presence of both orientational and substitutional disorders is inve... more The spectral diffusion in the presence of both orientational and substitutional disorders is investigated at 4.2 and 1.8 K. Our systems of study are different compmitions of solid solutions of 1-bromd-chloronaphthalene (BCN) and 1 &dibromonaphthalene (DBN). BCN is known to form an orientationally disordered solid. We used a wide range of concentrations within which the DBN crystal structure prevails. The phosphorescence of BCN was monitored as a function of the concentration of BCN. The analysis of our results shows that (i) the spectral diffusion is concentration dependent and, at very low concentration, the excitation is completely localized; (ii) as the concentration of BCN is increased, the onset of spectral diffusion is observed; (iii) above a critical concentration, the spectral diffusion rate increases rapidly; (iv) the process of spectral diffusion is highly temperature dependent. The concentration dependence behavior is found to be consistent with both the diffusion and the percolation models. From the analysis of the results, we conclude that the spectral diffusion in this system is phonon assisted and it involves cascading down in steps from higher to lower energy sites. Also, the theoretical analysis suggests that the excitation transport topology involves 2-dimensional exchange interactions.

Research paper thumbnail of Electrooptic effect in Langmuir-Blodgett films of 2-(docosylamino)-5-nitropyridine probed by surface plasmon waves

Langmuir, 1992

Measurements of electrooptic modulation of surface plasmon resonance have been carried out on hor... more Measurements of electrooptic modulation of surface plasmon resonance have been carried out on horizontally transferred Langmuir-Blodgett films of 2-(docosylamino)-5-nitropyridine. The observed Pockels response is approximately constant for different numbers of layers in multilayered films and is proportional to the strength of the modulating field. The calculated second-order susceptibility values are-2 x 10-13 m V 1 , 2 orders of magnitude lower than those derived from second harmonic generation studies. The presence of the Pockels effect is attributed to off-diagonal terms in the second-order susceptibility.

Research paper thumbnail of Research on nonlinear optical materials: an assessment

Research paper thumbnail of A Single-Organelle Optical Omics Platform for Cell Science and Biomarker Discovery

Research in fundamental cell biology and pathology could be revolutionized by developing the capa... more Research in fundamental cell biology and pathology could be revolutionized by developing the capacity for quantitative molecular analysis of subcellular structures. To that end, we introduce the Ramanomics platform, based on confocal Raman microspectrometry coupled to a biomolecular component analysis algorithm, which together enable us to molecularly profile single organelles in a live-cell environment. This emerging omics approach categorizes the entire molecular makeup of a sample into about a dozen of general classes and subclasses of biomolecules and quantifies their amounts in submicrometer volumes. A major contribution of our study is an attempt to bridge Raman spectrometry with big-data analysis in order to identify complex patterns of biomolecules in a single cellular organelle and leverage discovery of disease biomarkers. Our data reveal significant variations in organellar composition between different cell lines. We also demonstrate the merits of Ramanomics for identifying diseased cells by using prostate cancer as an example. We report large-scale molecular transformations in the mitochondria, Golgi apparatus, and endoplasmic reticulum that accompany the development of prostate cancer. Based on these findings, we propose that Ramanomics datasets in distinct organelles constitute signatures of cellular metabolism in healthy and diseased states.

Research paper thumbnail of Fluorescence lifetime imaging and its applications in cellular microenvironment measurement and auxiliary diagnosis

International Conference on Photonics and Imaging in Biology and Medicine, 2017

Research paper thumbnail of Small molecule based EGFR targeting of biodegradable nanoparticles containing temozolomide and Cy5 dye for greatly enhanced image-guided glioblastoma therapy

Nanomedicine: Nanotechnology, Biology and Medicine, 2021

Current glioblastoma multiform (GBM) treatment is insufficient, facing obstacles like poor tumor ... more Current glioblastoma multiform (GBM) treatment is insufficient, facing obstacles like poor tumor accumulation and dose limiting side effects of chemotherapeutic agents. Targeted nanomaterials offer breakthrough potential in GBM treatment; however, traditional antibody-based targeting poses challenges for live brain application. To overcome current obstacles, we introduce here the development of a small molecule targeting agent, CFMQ, coupled to biocompatible chitosan coated poly(lactic-co-glycolic) acid nanoparticles. These targeted nanoparticles enhance cellular uptake and show rapid blood-brain barrier (BBB) permeability in-vitro, demonstrating the ability to effectively deliver their load to tumor cells. Encapsulation of the chemotherapeutic agent, temozolomide (TMZ), decreases the IC50~34-fold compared to free-drug. Also, CFMQ synergistically suppresses tumor cell progression, reducing colony formation (98%), cell migration (84%), and cell invasion (77%). Co-encapsulation of Cy5 enables optical image guided therapy. This biocompatible theranostic nanoformulation shows early promise in significantly enhancing the efficacy of TMZ, while providing potential for image-guided therapy for GBM.

Research paper thumbnail of Laser-ablative synthesis of aggregation-induced enhanced emission luminophore dyes in aqueous solutions

Synthesis and Photonics of Nanoscale Materials XVI, 2019

Methods of femtosecond laser ablation in deionized water were used to fabricate ultrasmall (< ... more Methods of femtosecond laser ablation in deionized water were used to fabricate ultrasmall (< 2 nm), bare (ligand-free) organic luminophore DCEtDCS nanoparticles, which exhibit aggregation enhanced emission in the green range (533 nm) with the quantum yield exceeding 58% and provide no concentration quenching. In contrast to chemically synthesized counterparts, laser-synthesized DCEtDCS nanoparticles do not contain any organic impurities due to their preparation in aqueous medium and do not require surfactants to stabilize colloidal solutions, which makes them highly suitable for intracellular uptake and bioimaging. The highly negative surface charge of these nanoparticles impeded their cellular uptake, but when the surface was coated with chitosan, a cationic polymer, intracellular uptake in microglia was achieved. Using in vitro model, we finally demonstrate the efficient employment of ultrasmall and surfactant free fluorescent organic nanoparticles prepared by laser ablation as markers in bioimaging.

Research paper thumbnail of Organic Solvent and Surfactant Free Fluorescent Organic Nanoparticles by Laser Ablation of Aggregation‐Induced Enhanced Emission Dyes

Advanced Optical Materials, 2018

Less toxic and highly fluorescent nanoparticles are in high demand to image biological events and... more Less toxic and highly fluorescent nanoparticles are in high demand to image biological events and early-stage disease. We present a strategy to fabricate highly fluorescent organic nanoparticles by laser ablation of aggregation induced enhanced emission (AIE) luminophores, which are free of any organic solvent and surfactant. As these dyes

Research paper thumbnail of Synergic treatment of Alzheimer’s disease with brain targeted nanoparticles incorporating NgR-siRNA and brain derived neurotrophic factor

Smart Materials in Medicine, 2020

treatment of Alzheimer's disease with brain targeted nanoparticles incorporating NgR-siRNA and br... more treatment of Alzheimer's disease with brain targeted nanoparticles incorporating NgR-siRNA and brain derived neurotrophic factor, Smart Materials in Medicine,

Research paper thumbnail of Inside Cover: Cellular transformations in near‐infrared light‐induced apoptosis in cancer cells revealed by label‐free CARS imaging (J. Biophotonics 12/2019)

Journal of Biophotonics, 2019

Research paper thumbnail of ICG‐Sensitized NaYF 4 :Er Nanostructure for Theranostics

Advanced Optical Materials, 2018

played a substantial role in biomedical imaging. [1-3] These dielectric nanocrystals, doped with ... more played a substantial role in biomedical imaging. [1-3] These dielectric nanocrystals, doped with rare-earth ions, have generated significant interest as "nanovectors" with multiple capabilities such as biosensing, luminescent imaging, drug delivery, and theranostics. [4-14] Multimodal functionality is especially important in applications of nanoagents for therapeutic purposes, when the monitoring of a therapeutic process in real time is necessary for the treatment evaluation. Fluoride nanocrystals, doped with trivalent Erbium ions, are one of the most basic nanomaterials used in optical bioimaging. [1,2,15] This nanophosphor produces upconverted emission in the visible (≈540 and ≈650 nm) and Stokes-shift emission in the NIR wavelength range (≈1520 and ≈2800 nm) under NIR excitation at ≈808 nm. Emission centered at 1520 nm is in the second optical transparency window in the NIR range (NIR-II) and, therefore, can be used for bioimaging due to lower absorption and scattering by bioconstituents, compared to the visible light. [16] Despite the considerable capability of this nanomaterial for applications to bioscience, relatively low absorption by Er 3+ ions at ≈800 nm and low luminescence yield compared to the bulk materials require an optimization of nanoparticle optical parameters. Not always, this task could be performed by an increase in Er 3+ concentration. An optimal concentration of this component is within 1-2 mol% and further increasing Er 3+ concentration results in quenching of luminescence. There are other several strategies to improve the luminescence of nanoparticles. The use of core/shell architecture in the nanoparticles protects the luminescent ions in the core from nonradiative decay caused by surface defects as well as from vibrational deactivation by the environment in colloidal dispersions. [17-19] Employment of a photosensitizer such as Yb 3+ , which efficiently transfers the excitation to Er 3+ , [20-22] can significantly improve the emission intensity of nanomaterial. Surface plasmon enhancement using a coupled metallic nanostructure has also been used. [23-25] In this work, addressing the problem of low absorption of Er 3+-doped LNPs, we report the design and synthesis of indocyanine green (ICG) dye sensitized NaYF 4 :Er LNPs. ICG has strong absorption at 808 nm with large Stokes shifted emission band [6,26,27] that overlaps with the Er 3+ absorption band (Scheme 1), enabling efficient energy transfer from ICG to Er 3+ ions. Our group has recently demonstrated the application of

Research paper thumbnail of Applications of fluorescence lifetime imaging in clinical medicine

Journal of Innovative Optical Health Sciences, 2017

Fluorescence lifetime is not only associated with the molecular structure of fluorophores, but al... more Fluorescence lifetime is not only associated with the molecular structure of fluorophores, but also strongly depends on the environment around them, which allows fluorescence lifetime imaging microscopy (FLIM) to be used as a tool for precise measurement of the cell or tissue microenvironment. This review introduces the basic principle of fluorescence lifetime imaging technology and its application in clinical medicine, including research and diagnosis of diseases in skin, brain, eyes, mouth, bone, blood vessels and cavity organs, and drug evaluation. As a noninvasive, nontoxic and nonionizing radiation technique, FLIM demonstrates excellent performance with high sensitivity and specificity, which allows to determine precise position of the lesion and, thus, has good potential for application in biomedical research and clinical diagnosis.

Research paper thumbnail of Corrigendum: Resonance Raman Probes for Organelle-Specific Labeling in Live Cells

Scientific reports, Sep 2, 2016