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Heinrich Hofmann - One of the best experts on this subject based on the ideXlab platform.

  • significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle spion based core shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Margarethe Hofmannamtenbrink, Marcel De Vries, M M Motazacker, Farhad Rezaee, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in Nanomedicine have been concerned. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, the in vitro an d in vivo NPs' behaviors.. SuperParamagnetic Iron Oxide Nanoparticles (SPIONs) is one of the most prominent agents because of their superparamagnetic properties, useful for separation applications. To mimic surface properties of different type NPs, core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold.. The different surface SPION were incubated at a fixed serum:nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica surfaces where proteins preferred binding the neutral and positively charged. The importance of surface material on protein adsorption was also revealed by the preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials science, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Protein Corona Composition of Superparamagnetic Iron Oxide Nanoparticles with Various Physico-Chemical Properties and Coatings
    Scientific Reports, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Jatuporn Salaklang, Heinrich Hofmann
    Abstract:

    Because of their biocompatibility and unique magnetic properties, superparamagnetic iron oxide nanoparticles NPs (SPIONs) are recognized as some of the most prominent agents for theranostic applications. Thus, understanding the interaction of SPIONs with biological systems is important for their safe design and efficient applications. In this study, SPIONs were coated with 2 different Polymers: Polyvinyl Alcohol Polymer (PVA) and dextran. The obtained NPs with different surface charges (positive, neutral and negative) were used as a model study of the effect of surface charges and surface Polymer materials on protein adsorption using a magnetic separator. We found that the PVA-coated SPIONs with negative and neutral surface charge adsorbed more serum proteins than the dextran-coated SPIONs, which resulted in higher blood circulation time for PVA-coated NPs than the dextran-coated ones. Highly abundant proteins such as serum albumin, serotransferrin, prothrombin, alpha-fetoprotein and kininogen-1 were commonly found on both PVA- and dextran-coated SPIONs. By increasing the ionic strength, soft- and hard-corona proteins were observed on 3 types of PVA-SPIONs. However, the tightly bound proteins were observed only on negatively charged PVA-coated SPIONs after the strong protein elution.

Usawadee Sakulkhu - One of the best experts on this subject based on the ideXlab platform.

  • significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle spion based core shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Margarethe Hofmannamtenbrink, Marcel De Vries, M M Motazacker, Farhad Rezaee, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in Nanomedicine have been concerned. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, the in vitro an d in vivo NPs' behaviors.. SuperParamagnetic Iron Oxide Nanoparticles (SPIONs) is one of the most prominent agents because of their superparamagnetic properties, useful for separation applications. To mimic surface properties of different type NPs, core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold.. The different surface SPION were incubated at a fixed serum:nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica surfaces where proteins preferred binding the neutral and positively charged. The importance of surface material on protein adsorption was also revealed by the preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials science, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Protein Corona Composition of Superparamagnetic Iron Oxide Nanoparticles with Various Physico-Chemical Properties and Coatings
    Scientific Reports, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Jatuporn Salaklang, Heinrich Hofmann
    Abstract:

    Because of their biocompatibility and unique magnetic properties, superparamagnetic iron oxide nanoparticles NPs (SPIONs) are recognized as some of the most prominent agents for theranostic applications. Thus, understanding the interaction of SPIONs with biological systems is important for their safe design and efficient applications. In this study, SPIONs were coated with 2 different Polymers: Polyvinyl Alcohol Polymer (PVA) and dextran. The obtained NPs with different surface charges (positive, neutral and negative) were used as a model study of the effect of surface charges and surface Polymer materials on protein adsorption using a magnetic separator. We found that the PVA-coated SPIONs with negative and neutral surface charge adsorbed more serum proteins than the dextran-coated SPIONs, which resulted in higher blood circulation time for PVA-coated NPs than the dextran-coated ones. Highly abundant proteins such as serum albumin, serotransferrin, prothrombin, alpha-fetoprotein and kininogen-1 were commonly found on both PVA- and dextran-coated SPIONs. By increasing the ionic strength, soft- and hard-corona proteins were observed on 3 types of PVA-SPIONs. However, the tightly bound proteins were observed only on negatively charged PVA-coated SPIONs after the strong protein elution.

S Ram - One of the best experts on this subject based on the ideXlab platform.

  • formation of cr3 stabilized zro2 nanocrystals in a single cubic metastable phase by a novel chemical route with a sucrose Polyvinyl Alcohol Polymer matrix
    Materials Letters, 2001
    Co-Authors: Jagadish C. Ray, Panchanan Pramanik, S Ram
    Abstract:

    Abstract Cr 3+ -stabilized ZrO 2 nanocrystals in a single metastable cubic (c) phase are prepared by a novel chemical method using a Polymer matrix-based precursor with sucrose and Polyvinyl Alcohol. A pyrolysis of precursor over a hot plate at 250°C followed by calcination at temperatures between 400°C and 1000°C yields ZrO 2 nanocrystals in form of a powder. X-ray diffraction determines formation of a single c-ZrO 2 phase at 2–15 mol% Cr 3+ at 900°C or lower temperatures. Crystallites are in a near-spherical shape, 5–10-nm diameter, in electron micrograph as per the calcination temperature. A fast decomposition/combustion of Cr 3+ modified precursor over a narrow 250–500°C range during calcination controls formation of c-ZrO 2 nanocrystals in the confined size. It occurs with a vigorous exothermic signal with 70–80% loss in initial precursor mass. Average position of the exothermic peak shifts from 460°C to 442°C to 385°C at 1, 5 and 15 mol% Cr 3+ , respectively, in the precursor.

  • Formation of Cr3+ stabilized ZrO2 nanocrystals in a single cubic metastable phase by a novel chemical route with a sucrose–Polyvinyl Alcohol Polymer matrix
    Materials Letters, 2001
    Co-Authors: Jagadish C. Ray, Panchanan Pramanik, S Ram
    Abstract:

    Abstract Cr 3+ -stabilized ZrO 2 nanocrystals in a single metastable cubic (c) phase are prepared by a novel chemical method using a Polymer matrix-based precursor with sucrose and Polyvinyl Alcohol. A pyrolysis of precursor over a hot plate at 250°C followed by calcination at temperatures between 400°C and 1000°C yields ZrO 2 nanocrystals in form of a powder. X-ray diffraction determines formation of a single c-ZrO 2 phase at 2–15 mol% Cr 3+ at 900°C or lower temperatures. Crystallites are in a near-spherical shape, 5–10-nm diameter, in electron micrograph as per the calcination temperature. A fast decomposition/combustion of Cr 3+ modified precursor over a narrow 250–500°C range during calcination controls formation of c-ZrO 2 nanocrystals in the confined size. It occurs with a vigorous exothermic signal with 70–80% loss in initial precursor mass. Average position of the exothermic peak shifts from 460°C to 442°C to 385°C at 1, 5 and 15 mol% Cr 3+ , respectively, in the precursor.

Morteza Mahmoudi - One of the best experts on this subject based on the ideXlab platform.

  • significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle spion based core shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Margarethe Hofmannamtenbrink, Marcel De Vries, M M Motazacker, Farhad Rezaee, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials Science, 2015
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in Nanomedicine have been concerned. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, the in vitro an d in vivo NPs' behaviors.. SuperParamagnetic Iron Oxide Nanoparticles (SPIONs) is one of the most prominent agents because of their superparamagnetic properties, useful for separation applications. To mimic surface properties of different type NPs, core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold.. The different surface SPION were incubated at a fixed serum:nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica surfaces where proteins preferred binding the neutral and positively charged. The importance of surface material on protein adsorption was also revealed by the preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Significance of surface charge and shell material of superparamagnetic iron oxide nanoparticle (SPION) based core/shell nanoparticles on the composition of the protein corona
    Biomaterials science, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Geraldine Coullerez, Marcel De Vries, M M Motazacker, Farhad Rezaee, Margarethe Hofmann-amtenbrink, Heinrich Hofmann
    Abstract:

    As nanoparticles (NPs) are increasingly used in many applications their safety and efficient applications in nanomedicine have become concerns. Protein coronas on nanomaterials' surfaces can influence how the cell "recognizes" nanoparticles, as well as the in vitro and in vivo NPs' behaviors. The SuperParamagnetic Iron Oxide Nanoparticle (SPION) is one of the most prominent agents because of its superparamagnetic properties, which is useful for separation applications. To mimic surface properties of different types of NPs, a core-shell SPION library was prepared by coating with different surfaces: Polyvinyl Alcohol Polymer (PVA) (positive, neutral and negative), SiO2 (positive and negative), titanium dioxide and metal gold. The SPIONs with different surfaces were incubated at a fixed serum : nanoparticle surface ratio, magnetically trapped and washed. The tightly bound proteins were quantified and identified. The surface charge has a great impact on protein adsorption, especially on PVA and silica where proteins preferred binding to the neutral and positively charged surfaces. The importance of surface material on protein adsorption was also revealed by preferential binding on TiO2 and gold coated SPION, even negatively charged. There is no correlation between the protein net charge and the nanoparticle surface charge on protein binding, nor direct correlation between the serum proteins' concentration and the proteins detected in the coronas.

  • Protein Corona Composition of Superparamagnetic Iron Oxide Nanoparticles with Various Physico-Chemical Properties and Coatings
    Scientific Reports, 2014
    Co-Authors: Usawadee Sakulkhu, Morteza Mahmoudi, Lionel Maurizi, Jatuporn Salaklang, Heinrich Hofmann
    Abstract:

    Because of their biocompatibility and unique magnetic properties, superparamagnetic iron oxide nanoparticles NPs (SPIONs) are recognized as some of the most prominent agents for theranostic applications. Thus, understanding the interaction of SPIONs with biological systems is important for their safe design and efficient applications. In this study, SPIONs were coated with 2 different Polymers: Polyvinyl Alcohol Polymer (PVA) and dextran. The obtained NPs with different surface charges (positive, neutral and negative) were used as a model study of the effect of surface charges and surface Polymer materials on protein adsorption using a magnetic separator. We found that the PVA-coated SPIONs with negative and neutral surface charge adsorbed more serum proteins than the dextran-coated SPIONs, which resulted in higher blood circulation time for PVA-coated NPs than the dextran-coated ones. Highly abundant proteins such as serum albumin, serotransferrin, prothrombin, alpha-fetoprotein and kininogen-1 were commonly found on both PVA- and dextran-coated SPIONs. By increasing the ionic strength, soft- and hard-corona proteins were observed on 3 types of PVA-SPIONs. However, the tightly bound proteins were observed only on negatively charged PVA-coated SPIONs after the strong protein elution.

Misook Kang - One of the best experts on this subject based on the ideXlab platform.

  • bright green emission from f mwcnt embedded co doped bi3 tb3 Polyvinyl Alcohol Polymer nanocomposites for photonic applications
    RSC Advances, 2017
    Co-Authors: Naveen K Kumar, R. Padma, Y.c. Ratnakaram, Misook Kang
    Abstract:

    A bright, dazzling green emission has been obtained from functionalized multi walled carbon nanotube (f-MWCNTs)-embedded Bi3+ + Tb3+:PVA Polymer nanocomposites under UV excitation. We successfully synthesized Tb3+:PVA, Bi3+ + Tb3+:PVA and Bi3+ + Tb3+ + f-MWCNTs:PVA Polymer films by a solution casting method. For these Polymer films, their XRD and FTIR spectral profiles were analyzed for structural details and ion–Polymer interaction mechanism. Tb3+ doped at different concentrations in PVA Polymer films displayed a green emission at 546 nm (5D4 → 7F5) under 370 nm (7F6 → 5L10) excitation. Upon co-doping with Bi3+ in the Tb3+:PVA Polymer film, the film exhibits enriched green emission compared to single Tb3+:PVA under 320 nm excitation due to the energy transfer from Bi3+ to Tb3+. Surprisingly, a common excitation band was found at 320 nm for Tb3+, Bi3+ and f-MWCNTs. After dispersion of the f-MWCNTs in the co-doped Bi3++Tb3+:PVA Polymer films, the photoluminescence properties were remarkably enhanced, and a prominent green emission was observed at 546 nm. The green emission of Tb3+ is significantly enhanced though an efficient energy transfer process from Bi3+ to Tb3+ and f-MWCNTs to Tb3+. The possible energy transfer mechanism was clearly demonstrated via several fluorescent methods. The energy transfer mechanism was substantiated with fluorescence lifetime decay dynamics. From these results, these f-MWCNTs-embedded Bi3++Tb3+:PVA Polymer films could be suggested as promising candidates for green luminescent materials for photonic devices.

  • Bright green emission from f-MWCNT embedded co-doped Bi3+ + Tb3+:Polyvinyl Alcohol Polymer nanocomposites for photonic applications
    RSC Advances, 2017
    Co-Authors: K. Naveen Kumar, R. Padma, Y.c. Ratnakaram, Misook Kang
    Abstract:

    A bright, dazzling green emission has been obtained from functionalized multi walled carbon nanotube (f-MWCNTs)-embedded Bi3+ + Tb3+:PVA Polymer nanocomposites under UV excitation. We successfully synthesized Tb3+:PVA, Bi3+ + Tb3+:PVA and Bi3+ + Tb3+ + f-MWCNTs:PVA Polymer films by a solution casting method. For these Polymer films, their XRD and FTIR spectral profiles were analyzed for structural details and ion–Polymer interaction mechanism. Tb3+ doped at different concentrations in PVA Polymer films displayed a green emission at 546 nm (5D4 → 7F5) under 370 nm (7F6 → 5L10) excitation. Upon co-doping with Bi3+ in the Tb3+:PVA Polymer film, the film exhibits enriched green emission compared to single Tb3+:PVA under 320 nm excitation due to the energy transfer from Bi3+ to Tb3+. Surprisingly, a common excitation band was found at 320 nm for Tb3+, Bi3+ and f-MWCNTs. After dispersion of the f-MWCNTs in the co-doped Bi3++Tb3+:PVA Polymer films, the photoluminescence properties were remarkably enhanced, and a prominent green emission was observed at 546 nm. The green emission of Tb3+ is significantly enhanced though an efficient energy transfer process from Bi3+ to Tb3+ and f-MWCNTs to Tb3+. The possible energy transfer mechanism was clearly demonstrated via several fluorescent methods. The energy transfer mechanism was substantiated with fluorescence lifetime decay dynamics. From these results, these f-MWCNTs-embedded Bi3++Tb3+:PVA Polymer films could be suggested as promising candidates for green luminescent materials for photonic devices.

  • Energy transfer (In3+ → Eu3+) based Polyvinyl Alcohol Polymer composites for bright red luminescence
    Optical Materials, 2017
    Co-Authors: K. Naveen Kumar, Misook Kang, L. Vijayalakshmi, Jong Su Kim, Jaesool Shim, Migyung Cho, Bipin Kumar Gupta
    Abstract:

    Abstract A prominent sensitization effect of In 3+ ions is observed in In 3+ +Eu 3+ : PVA Polymer composites under UV excitation. Consequently, it enhances the red emission performance of Eu 3+ ions in PVA system. We have successfully synthesized Eu 3+ : PVA, In 3+ : PVA and In 3+ +Eu 3+ : PVA Polymer films by traditional solution casting method. The structural and ion-Polymer interaction studies have been analyzed from XRD and FTIR spectral profiles. Eu 3+ doped PVA Polymer composites are exhibited a red emission at 619 nm ( 5 D 0 → 7 F 2 ) under 396 nm ( 7 F 0 → 5 L 6 ) of excitation. Upon co-doping with In 3+ ions in different concentrations to the Eu 3+ : PVA Polymer film, it exhibits predominant red emission than singly doped Eu 3+ : PVA under 396 nm of excitation due to energy migration from In 3+ to Eu 3+ . Successful emission photons of In 3+ ions are collectively absorbed by the Eu 3+ ions which lead the improvement of red emission. Optimized sensitization concentration of the In 3+ ions has been found to be 0.01 wt%. Possible energy migration phenomenon is elucidated by several fluorescent dynamics. The energy transfer process is substantiated by lifetime decay analysis and overlapped spectral studies. The Commission International de I-Eclairage chromaticity coordinates were calculated. The quantum efficiencies of the Eu 3+ ions and In 3+ ions in singly doped and co-doped Polymer systems have been evaluated. From these results, these co-doped In 3+ +Eu 3+ : PVA composite Polymer films might be proposed as encouraging candidates for bright red fluorescent materials for several photonic applications.