In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core-shell nanoparticles （Ag@AuNPs） and the Ag/Au hollow nanocages （Ag/AuNCs） with Ag nanoparticles （AgNPs） as se...In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core-shell nanoparticles （Ag@AuNPs） and the Ag/Au hollow nanocages （Ag/AuNCs） with Ag nanoparticles （AgNPs） as seeds by adjusting pH, and the preparation of hybrid Ag@AuNPs- or Ag/AuNCs-graphene oxide nanocomposites （Ag@AuNPs-GO or Ag/AuNCs-GO） based on the self-assembly. It was noticed from the elec- trostatic assembly experiment that the loading amount of Ag/AuNCs on GO nanosheet was more than that of Ag@AuNPs. The as-synthesized hybrid materials were characterized by transmission electron microscopy, atomic force microscopy, ξ-potential, high-angle annular dark- field scanning transmission electron microscopy, thermo- gravimetric analyzer and X-ray diffraction. Catalytic activities of Ag@AuNPs, Ag/AuNCs and Ag/AuNCs-GO nanostructures were investigated in the reduction of 4-, 3-or 2-nitrophenol to 4-, 3- or 2-aminophenol, and on the basis of comparative kinetic studies the following trend was obtained for the related catalytic activity： Ag/AuNCs- GO 〉 Ag/AuNCs 〉 Ag@AuNPs. These observations were attributed to the simultaneous effects of surface area available for catalytic reaction and composition of the hybrid nanostructures.展开更多
A major goal of environmental agencies today is to conduct point-of-collection monitoring of excess inorganic phosphate(Pi)in environmental water samples for tracking aquatic“dead zones”caused by algae blooms.Howeve...A major goal of environmental agencies today is to conduct point-of-collection monitoring of excess inorganic phosphate(Pi)in environmental water samples for tracking aquatic“dead zones”caused by algae blooms.However,there are no existing commercial devices which have been miniaturized and are suitable for the point-of-need-testing(“PONT”)that is required to fully map a large region,such as the Florida Everglades.To solve this challenge,a reflection-mode fluorescence-sensing apparatus was developed,leveraging an environmentally sensitive fluorophore(MDCC)bound to a bacterial phosphate-binding protein to generate a fluorescent optical signal proportional to the concentration of(Pi)present.The combined end-to-end integrated sensor system had a response time of only 4 s,with minimal effects of common interfering agents and a linear range spanning from 1.1 to 64 ppb.To support easeof-use during PONT,the platform incorporated disposable wax-printed paper strip sample pads and a smartphone camera detection system.Since the EPA threshold is currently 30 ppb to prevent eutrophication,this system serves as a rapid test of whether a region is compliant.展开更多
Alzheimer’s disease(AD)is a neurodegenerative disease.It is a type of dementia and it mainly deals with thinking,memory and behavioral aspects.It is a progressive disease,which in course of time damages most sections...Alzheimer’s disease(AD)is a neurodegenerative disease.It is a type of dementia and it mainly deals with thinking,memory and behavioral aspects.It is a progressive disease,which in course of time damages most sections of the brain.Beta amyloid peptides(Aβ)have been recognized as potential biomarkers to monitor AD.The Ab protein is made up of 39–42 amino acids,which are the main components of the plaques found in the AD brain.This beta amyloid is toxic to the neurons and causes degeneration.In order to measure these biomarkers,nanobiosensing techniques are used.Timely monitoring of Ab levels helps in the detection of the irreversible disease called AD.These techniques fall in two categories,viz.,in vitro and in vivo.Several techniques like electrochemical techniques,cantilever-based liposome biosensor,ELISA,PET scan,microdialysis,etc.,are discussed further in the article.These techniques can prove to be effective methods for quantifying amyloid deposition within specific brain regions.展开更多
Cancer is a serious threat to human health.Survival rates of cancer patients are highly dependent on the early diagnosis and treatment.Carbon nanodots(CDs),a rising star of carbon nanomaterial family,can be developed ...Cancer is a serious threat to human health.Survival rates of cancer patients are highly dependent on the early diagnosis and treatment.Carbon nanodots(CDs),a rising star of carbon nanomaterial family,can be developed as a promising terrace for cell labeling,bioimaging,drug delivery,diagnosis,and therapy by virtue of many superior properties including unique photo-luminescence properties,low toxicity,excellent biocompatibility,and easy functionalization.In this mini review,we present the recent progress in fundamental properties of CDs,and highlight their bioapplications in cancer diagnosis and treatment.展开更多
A label-free colorimetric protocol based on peptide nucleic acid/silver nanoparticles(PNA/Ag NPs) has been initially proposed for specific recognition of m RNA.Making use of the controlled silver nanoparticles aggrega...A label-free colorimetric protocol based on peptide nucleic acid/silver nanoparticles(PNA/Ag NPs) has been initially proposed for specific recognition of m RNA.Making use of the controlled silver nanoparticles aggregation/dispersion by PNA/PNA–RNA complex, proto-oncogene c-Myc m RNA detection can be achieved. Moreover, the PNA/Ag NPs platform can undergo color change in response to target c-Myc m RNA with single-base-mismatch sensitivity, which could further help in visually identify single nucleotide differences in target genes.展开更多
In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core–shell nanoparticles(Ag@Au NPs) and the Ag/Au hollow nanocages(Ag/Au NCs) with Ag nanoparticles(Ag NPs) as seeds b...In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core–shell nanoparticles(Ag@Au NPs) and the Ag/Au hollow nanocages(Ag/Au NCs) with Ag nanoparticles(Ag NPs) as seeds by adjusting p H, and the preparation of hybrid Ag@Au NPs- or Ag/Au NCs-graphene oxide nanocomposites(Ag@Au NPs-GO or Ag/Au NCs-GO)based on the self-assembly. It was noticed from the electrostatic assembly experiment that the loading amount of Ag/Au NCs on GO nanosheet was more than that of Ag@Au NPs. The as-synthesized hybrid materials were characterized by transmission electron microscopy, atomic force microscopy, f-potential, high-angle annular darkfield scanning transmission electron microscopy, thermogravimetric analyzer and X-ray diffraction. Catalytic activities of Ag@Au NPs, Ag/Au NCs and Ag/Au NCs-GO nanostructures were investigated in the reduction of 4-, 3-or 2-nitrophenol to 4-, 3- or 2-aminophenol, and on the basis of comparative kinetic studies the following trend was obtained for the related catalytic activity: Ag/Au NCsGO [ Ag/Au NCs [ Ag@Au NPs. These observations were attributed to the simultaneous effects of surface area available for catalytic reaction and composition of the hybrid nanostructures.展开更多
Sweat-based diagnostics offer an exciting avenue to noninvasively monitor analytes which had previously only been avail-able through painful blood draws.Sweat is enriched with physiologically valuable information,and ...Sweat-based diagnostics offer an exciting avenue to noninvasively monitor analytes which had previously only been avail-able through painful blood draws.Sweat is enriched with physiologically valuable information,and recent proteomic studies have identified numerous critical analytes which have highly correlated levels in blood,interstitial fluid and sweat.How-ever,usage of sweat for health monitoring has not been studied extensively due to the substantial challenge of assembling a composite clinic-ready device.Recent advances in soft electronics have made this goal realizable,as these devices can perform electronic or optical monitoring on a flexible substrate using small volumes of liquid.While this field is still in its infancy,this review examines the physiological composition of sweat,various improvements in material science that improve sensor design,existing FDA approvals,methods of extracting sweat and comparisons to blood-based tests.Furthermore,this review assesses the critical challenges which must be overcome for this type of technology to make it out of research laboratories and into continuous clinical use.We believe that once properly harnessed,sweat-based diagnostics can provide patients a painless monitoring tool which can be customized to track a wide variety of medical conditions from the comfort of a patient’s own home.展开更多
In this research, we explored a rapid assessment of silver nanoparticles(Ag-NPs) neurotoxicity at a single-cell level. Traditional nanotoxicity assays on large cell-populations may hide the important heterogeneity of ...In this research, we explored a rapid assessment of silver nanoparticles(Ag-NPs) neurotoxicity at a single-cell level. Traditional nanotoxicity assays on large cell-populations may hide the important heterogeneity of individual cells often found in neuronal cells. The development in the area of new nanomaterial discoveries is far ahead of the development of advanced tools to measure these materials' toxicity. Development of alternative approaches to assess nanomaterials toxicity rapidly, reliably, and accurately is desirable. Here, we present a chip-based, cell-integrated microwell-array device for rapid assessment of neurotoxicity of Ag-NPs by monitoring the exocytosis function of a PC12 cell. Results presented here confirm the dose-dependent toxicity of Ag-NPs and the immediate alteration of their exocytosis function when exposed to NPs.展开更多
基金Acknowledgments This work was supported by the National Nalural Science Foundation of China （21 105042）, the Science Foundation of China Postdoctor （2014M560572）, the Natural Science Foundation of Shandong Province IZR2015BM024）, and Tai-Shan Scholar Research Fund of Shandong Province. The sludy was partially supported by grant NIH IR01DA037838 to Drs. Li and Nair.
文摘In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core-shell nanoparticles （Ag@AuNPs） and the Ag/Au hollow nanocages （Ag/AuNCs） with Ag nanoparticles （AgNPs） as seeds by adjusting pH, and the preparation of hybrid Ag@AuNPs- or Ag/AuNCs-graphene oxide nanocomposites （Ag@AuNPs-GO or Ag/AuNCs-GO） based on the self-assembly. It was noticed from the elec- trostatic assembly experiment that the loading amount of Ag/AuNCs on GO nanosheet was more than that of Ag@AuNPs. The as-synthesized hybrid materials were characterized by transmission electron microscopy, atomic force microscopy, ξ-potential, high-angle annular dark- field scanning transmission electron microscopy, thermo- gravimetric analyzer and X-ray diffraction. Catalytic activities of Ag@AuNPs, Ag/AuNCs and Ag/AuNCs-GO nanostructures were investigated in the reduction of 4-, 3-or 2-nitrophenol to 4-, 3- or 2-aminophenol, and on the basis of comparative kinetic studies the following trend was obtained for the related catalytic activity： Ag/AuNCs- GO 〉 Ag/AuNCs 〉 Ag@AuNPs. These observations were attributed to the simultaneous effects of surface area available for catalytic reaction and composition of the hybrid nanostructures.
基金The authors would like to acknowledge the financial support by the National Science Foundation under NSF Cooperative Agreement(No.EEC-1648451 and No.EEC-1647837)。
文摘A major goal of environmental agencies today is to conduct point-of-collection monitoring of excess inorganic phosphate(Pi)in environmental water samples for tracking aquatic“dead zones”caused by algae blooms.However,there are no existing commercial devices which have been miniaturized and are suitable for the point-of-need-testing(“PONT”)that is required to fully map a large region,such as the Florida Everglades.To solve this challenge,a reflection-mode fluorescence-sensing apparatus was developed,leveraging an environmentally sensitive fluorophore(MDCC)bound to a bacterial phosphate-binding protein to generate a fluorescent optical signal proportional to the concentration of(Pi)present.The combined end-to-end integrated sensor system had a response time of only 4 s,with minimal effects of common interfering agents and a linear range spanning from 1.1 to 64 ppb.To support easeof-use during PONT,the platform incorporated disposable wax-printed paper strip sample pads and a smartphone camera detection system.Since the EPA threshold is currently 30 ppb to prevent eutrophication,this system serves as a rapid test of whether a region is compliant.
基金This research work is partially supported by the grants NIH 1R01DA037838-01partially by Hundred Talent Project of Shanxi Province.
文摘Alzheimer’s disease(AD)is a neurodegenerative disease.It is a type of dementia and it mainly deals with thinking,memory and behavioral aspects.It is a progressive disease,which in course of time damages most sections of the brain.Beta amyloid peptides(Aβ)have been recognized as potential biomarkers to monitor AD.The Ab protein is made up of 39–42 amino acids,which are the main components of the plaques found in the AD brain.This beta amyloid is toxic to the neurons and causes degeneration.In order to measure these biomarkers,nanobiosensing techniques are used.Timely monitoring of Ab levels helps in the detection of the irreversible disease called AD.These techniques fall in two categories,viz.,in vitro and in vivo.Several techniques like electrochemical techniques,cantilever-based liposome biosensor,ELISA,PET scan,microdialysis,etc.,are discussed further in the article.These techniques can prove to be effective methods for quantifying amyloid deposition within specific brain regions.
基金the National Natural Science Foundation of China(21575084)the Natural Science Foundation of Shanxi Province(201701D121019).
文摘Cancer is a serious threat to human health.Survival rates of cancer patients are highly dependent on the early diagnosis and treatment.Carbon nanodots(CDs),a rising star of carbon nanomaterial family,can be developed as a promising terrace for cell labeling,bioimaging,drug delivery,diagnosis,and therapy by virtue of many superior properties including unique photo-luminescence properties,low toxicity,excellent biocompatibility,and easy functionalization.In this mini review,we present the recent progress in fundamental properties of CDs,and highlight their bioapplications in cancer diagnosis and treatment.
基金the National Natural Science Foundation of China (21305058, 21205056, 21075058 and 21503104)Tai-Shan Scholar Research Fund of Shandong Province
文摘A label-free colorimetric protocol based on peptide nucleic acid/silver nanoparticles(PNA/Ag NPs) has been initially proposed for specific recognition of m RNA.Making use of the controlled silver nanoparticles aggregation/dispersion by PNA/PNA–RNA complex, proto-oncogene c-Myc m RNA detection can be achieved. Moreover, the PNA/Ag NPs platform can undergo color change in response to target c-Myc m RNA with single-base-mismatch sensitivity, which could further help in visually identify single nucleotide differences in target genes.
基金supported by the National Natural Science Foundation of China(21105042)the Science Foundation of China Postdoctor(2014M560572)+2 种基金the Natural Science Foundation of Shandong Province(ZR2015BM024)Tai-Shan Scholar Research Fund of Shandong Provincesupported by grant NIH 1R01DA037838 to Drs.Li and Nair
文摘In this work, we demonstrated a simple and efficacious two-step method for the synthesis of Ag@Au core–shell nanoparticles(Ag@Au NPs) and the Ag/Au hollow nanocages(Ag/Au NCs) with Ag nanoparticles(Ag NPs) as seeds by adjusting p H, and the preparation of hybrid Ag@Au NPs- or Ag/Au NCs-graphene oxide nanocomposites(Ag@Au NPs-GO or Ag/Au NCs-GO)based on the self-assembly. It was noticed from the electrostatic assembly experiment that the loading amount of Ag/Au NCs on GO nanosheet was more than that of Ag@Au NPs. The as-synthesized hybrid materials were characterized by transmission electron microscopy, atomic force microscopy, f-potential, high-angle annular darkfield scanning transmission electron microscopy, thermogravimetric analyzer and X-ray diffraction. Catalytic activities of Ag@Au NPs, Ag/Au NCs and Ag/Au NCs-GO nanostructures were investigated in the reduction of 4-, 3-or 2-nitrophenol to 4-, 3- or 2-aminophenol, and on the basis of comparative kinetic studies the following trend was obtained for the related catalytic activity: Ag/Au NCsGO [ Ag/Au NCs [ Ag@Au NPs. These observations were attributed to the simultaneous effects of surface area available for catalytic reaction and composition of the hybrid nanostructures.
基金the National Science Foundation under NSF Cooperative Agreement(Nos.EEC-1648451 and EEC-1647837)Dr.Li also thanks the support sponsored by NSF Independent Research/Development(IRD)Program.
文摘Sweat-based diagnostics offer an exciting avenue to noninvasively monitor analytes which had previously only been avail-able through painful blood draws.Sweat is enriched with physiologically valuable information,and recent proteomic studies have identified numerous critical analytes which have highly correlated levels in blood,interstitial fluid and sweat.How-ever,usage of sweat for health monitoring has not been studied extensively due to the substantial challenge of assembling a composite clinic-ready device.Recent advances in soft electronics have made this goal realizable,as these devices can perform electronic or optical monitoring on a flexible substrate using small volumes of liquid.While this field is still in its infancy,this review examines the physiological composition of sweat,various improvements in material science that improve sensor design,existing FDA approvals,methods of extracting sweat and comparisons to blood-based tests.Furthermore,this review assesses the critical challenges which must be overcome for this type of technology to make it out of research laboratories and into continuous clinical use.We believe that once properly harnessed,sweat-based diagnostics can provide patients a painless monitoring tool which can be customized to track a wide variety of medical conditions from the comfort of a patient’s own home.
基金supported by the National Natural Science Foundation of China(21273181,21328501)the Tai-Shan Scholar Research Fund of Shandong Province+1 种基金the China Ocean Mineral Resources R&D Association project(DY125-15-T-08)the China Scholarship Council for their support
文摘In this research, we explored a rapid assessment of silver nanoparticles(Ag-NPs) neurotoxicity at a single-cell level. Traditional nanotoxicity assays on large cell-populations may hide the important heterogeneity of individual cells often found in neuronal cells. The development in the area of new nanomaterial discoveries is far ahead of the development of advanced tools to measure these materials' toxicity. Development of alternative approaches to assess nanomaterials toxicity rapidly, reliably, and accurately is desirable. Here, we present a chip-based, cell-integrated microwell-array device for rapid assessment of neurotoxicity of Ag-NPs by monitoring the exocytosis function of a PC12 cell. Results presented here confirm the dose-dependent toxicity of Ag-NPs and the immediate alteration of their exocytosis function when exposed to NPs.
