Poliraju Kalluru - Academia.edu (original) (raw)
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Papers by Poliraju Kalluru
Mxenes and their Composites, 2022
Angewandte Chemie International Edition, 2013
Biomaterials, 2014
Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, l... more Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorodin-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O 2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (w150 mW/cm 2 ), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging þ NmPDT þ NmPTT) upon single photon NIR light excitation under ultra-low laser doses.
Angewandte Chemie International Edition, 2013
Advanced Functional Materials, 2016
Biomaterials, 2016
Cancer is one of the major life-threatening diseases among human beings. Developing a simple, cos... more Cancer is one of the major life-threatening diseases among human beings. Developing a simple, cost-effective and biocompatible approach to treat cancers using ultra-low doses of light is a grand challenge in clinical cancer treatments. In this study, we report for the first time that nano-sized graphene oxide (GO) exhibits single-photon excitation wavelength dependent photoluminescence in the visible and short near-infrared (NIR) region, suitable for in vivo multi-color fluorescence imaging. We also demonstrate in both in vitro and in vivo experiments to show that nano GO can sensitize the formation of singlet oxygen to exert combined nanomaterial-mediated photodynamic therapeutic (NmPDT) and photothermal therapy (NmPTT) effects on the destruction of B16F0 melanoma tumors in mice using ultra-low doses (∼0.36 W/cm(2)) of NIR (980 nm) light. The average half-life span of the mice treated by the GO-PEG-folate-mediated NmPDT effects is beyond 30 days, which is ∼1.8 times longer than the mice treated with doxorubicin (17 days). Overall, the current study points out a successful example of using GO-PEG-folate nanocomposite as a theranostic nanomedicine to exert simultaneously in vivo fluorescent imaging as well as combined NmPDT and NmPTT effects for clinical cancer treatments.
Nanomaterials have been widely used in the biomedical field as gene/drug carriers, magnetic reson... more Nanomaterials have been widely used in the biomedical field as gene/drug carriers, magnetic resonance imaging (MRI) contrast reagents, photothermal therapy reagents, fluorescent cellular markers, etc. The origins and working mechanisms of cytotoxicities of nanomaterials, however, are not well understood. It is often stated in the literature that a nanomaterial is non-toxic and biocompatible. In this study, we show that the short term cytotoxicity of a nanomaterial is determined by the surface functionality, rather than the core nanomaterial. A so-called "non-toxic and biocompatible" nanomaterial, such as core/shell iron-filled carbon nanoparticles (Fe@CNPs) and nanodiamonds (NDs), can become cytotoxic when a cationic surface functionality, such as imidazolium (IM) and tertiary methyl ammonium ethyl methacrylate (TMAEA) moieties, was grafted onto the surface. To investigate the contributions of surface functionalities and the core nanomaterials on cytotoxicity, two "non-toxic and biocompatible" Fe@CNPs and NDs were surface-modified with different surface functionalities, including anionic COOH, zwitterionic PVP, neutral OH, cationic IM and TMAEA, and investigated for their cytotoxicities in both in vitro cancer cells (HeLa and U-87MG cells) and in vivo embryo development of zebrafish. Among these surface functionalities, cationic IM and TMAEA functionalities of both Fe@CNPs and NDs cause acute cytotoxicity to a similar extent in the in vitro cancer cell experiments, as well as affect severely the embryonic development and survival rates of zebrafish. Other surface functionalities do not show particularly strong cytotoxicities. To obtain information regarding the origins of cytotoxicities, the effects of surface functionalities were also examined on the lactate dehydrogenase (LDH) levels, cellular ROS generation, apoptosis, and changes in lysosomal membrane integrity, mitochondrial membrane potential, the intracellular pH (pH i ), and cell cycles. Our results clearly point out that surface functionality, rather than the core nanomaterials, plays a critical role in dictating the short-term cytotoxicities. † Electronic supplementary information (ESI) available: Schematic for the surface functionalization process, FT-IR, DLS, zeta-potential, PL spectra, cell viability in U-87MG cells and zebrash survival rates. See
This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its... more This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its stabilization using naturally occurring milk protein, casein. The synthesis of casein reduced graphene oxide (CRGO) was completed within 7 h under reflux at 90C with the formation of few layered fine graphene nanosheets. UV–Vis, XRD, XPS analysis data revealed the reduction process of the graphene oxide. Results of FT-IR, HPLC and TEM analysis have shown that the ensuing material consists of graphene decorated with casein molecules. Aspartic acid and glutamic acid residue present in casein molecules are responsible for the reduction of graphene oxide
Biomaterials, 2014
Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, l... more Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorodin-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O 2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (w150 mW/cm 2 ), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging þ NmPDT þ NmPTT) upon single photon NIR light excitation under ultra-low laser doses.
Angewandte Chemie International Edition, 2013
Angewandte Chemie International Edition, 2013
A green one step facile synthesis of graphene nanosheets byTerminalia chebula(T. chebula) extract... more A green one step facile synthesis of graphene nanosheets byTerminalia chebula(T. chebula) extract
mediated reduction of graphite oxide (GO) is reported in this work. This method avoids the use of harmful
toxic reducing agents. The comparative results of various characterizations of GO andT. chebulareduced
graphene oxide (TCG) provide a strong indication of the exclusion of oxygen containing groups from
graphene oxide and successive stabilization of the formed reduced graphene oxide (RGO). The
functionalization of reduced graphene oxide with the oxidized polyphenols causes their stability by
preventing the aggregation. We also have proposed how the oxidized polyphenols are accountable for
the stabilization of the formed graphene sheets.
Mxenes and their Composites, 2022
Angewandte Chemie International Edition, 2013
Biomaterials, 2014
Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, l... more Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorodin-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O 2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (w150 mW/cm 2 ), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging þ NmPDT þ NmPTT) upon single photon NIR light excitation under ultra-low laser doses.
Angewandte Chemie International Edition, 2013
Advanced Functional Materials, 2016
Biomaterials, 2016
Cancer is one of the major life-threatening diseases among human beings. Developing a simple, cos... more Cancer is one of the major life-threatening diseases among human beings. Developing a simple, cost-effective and biocompatible approach to treat cancers using ultra-low doses of light is a grand challenge in clinical cancer treatments. In this study, we report for the first time that nano-sized graphene oxide (GO) exhibits single-photon excitation wavelength dependent photoluminescence in the visible and short near-infrared (NIR) region, suitable for in vivo multi-color fluorescence imaging. We also demonstrate in both in vitro and in vivo experiments to show that nano GO can sensitize the formation of singlet oxygen to exert combined nanomaterial-mediated photodynamic therapeutic (NmPDT) and photothermal therapy (NmPTT) effects on the destruction of B16F0 melanoma tumors in mice using ultra-low doses (∼0.36 W/cm(2)) of NIR (980 nm) light. The average half-life span of the mice treated by the GO-PEG-folate-mediated NmPDT effects is beyond 30 days, which is ∼1.8 times longer than the mice treated with doxorubicin (17 days). Overall, the current study points out a successful example of using GO-PEG-folate nanocomposite as a theranostic nanomedicine to exert simultaneously in vivo fluorescent imaging as well as combined NmPDT and NmPTT effects for clinical cancer treatments.
Nanomaterials have been widely used in the biomedical field as gene/drug carriers, magnetic reson... more Nanomaterials have been widely used in the biomedical field as gene/drug carriers, magnetic resonance imaging (MRI) contrast reagents, photothermal therapy reagents, fluorescent cellular markers, etc. The origins and working mechanisms of cytotoxicities of nanomaterials, however, are not well understood. It is often stated in the literature that a nanomaterial is non-toxic and biocompatible. In this study, we show that the short term cytotoxicity of a nanomaterial is determined by the surface functionality, rather than the core nanomaterial. A so-called "non-toxic and biocompatible" nanomaterial, such as core/shell iron-filled carbon nanoparticles (Fe@CNPs) and nanodiamonds (NDs), can become cytotoxic when a cationic surface functionality, such as imidazolium (IM) and tertiary methyl ammonium ethyl methacrylate (TMAEA) moieties, was grafted onto the surface. To investigate the contributions of surface functionalities and the core nanomaterials on cytotoxicity, two "non-toxic and biocompatible" Fe@CNPs and NDs were surface-modified with different surface functionalities, including anionic COOH, zwitterionic PVP, neutral OH, cationic IM and TMAEA, and investigated for their cytotoxicities in both in vitro cancer cells (HeLa and U-87MG cells) and in vivo embryo development of zebrafish. Among these surface functionalities, cationic IM and TMAEA functionalities of both Fe@CNPs and NDs cause acute cytotoxicity to a similar extent in the in vitro cancer cell experiments, as well as affect severely the embryonic development and survival rates of zebrafish. Other surface functionalities do not show particularly strong cytotoxicities. To obtain information regarding the origins of cytotoxicities, the effects of surface functionalities were also examined on the lactate dehydrogenase (LDH) levels, cellular ROS generation, apoptosis, and changes in lysosomal membrane integrity, mitochondrial membrane potential, the intracellular pH (pH i ), and cell cycles. Our results clearly point out that surface functionality, rather than the core nanomaterials, plays a critical role in dictating the short-term cytotoxicities. † Electronic supplementary information (ESI) available: Schematic for the surface functionalization process, FT-IR, DLS, zeta-potential, PL spectra, cell viability in U-87MG cells and zebrash survival rates. See
This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its... more This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its stabilization using naturally occurring milk protein, casein. The synthesis of casein reduced graphene oxide (CRGO) was completed within 7 h under reflux at 90C with the formation of few layered fine graphene nanosheets. UV–Vis, XRD, XPS analysis data revealed the reduction process of the graphene oxide. Results of FT-IR, HPLC and TEM analysis have shown that the ensuing material consists of graphene decorated with casein molecules. Aspartic acid and glutamic acid residue present in casein molecules are responsible for the reduction of graphene oxide
Biomaterials, 2014
Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, l... more Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorodin-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O 2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (w150 mW/cm 2 ), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging þ NmPDT þ NmPTT) upon single photon NIR light excitation under ultra-low laser doses.
Angewandte Chemie International Edition, 2013
Angewandte Chemie International Edition, 2013
A green one step facile synthesis of graphene nanosheets byTerminalia chebula(T. chebula) extract... more A green one step facile synthesis of graphene nanosheets byTerminalia chebula(T. chebula) extract
mediated reduction of graphite oxide (GO) is reported in this work. This method avoids the use of harmful
toxic reducing agents. The comparative results of various characterizations of GO andT. chebulareduced
graphene oxide (TCG) provide a strong indication of the exclusion of oxygen containing groups from
graphene oxide and successive stabilization of the formed reduced graphene oxide (RGO). The
functionalization of reduced graphene oxide with the oxidized polyphenols causes their stability by
preventing the aggregation. We also have proposed how the oxidized polyphenols are accountable for
the stabilization of the formed graphene sheets.