Enantiomeric discrimination plays a crucial role in various scientific domains,including analytical chemistry,chemical biology,pharmaceuticals,and pesticide research.A variety of theoretical frameworks and chiroptical...Enantiomeric discrimination plays a crucial role in various scientific domains,including analytical chemistry,chemical biology,pharmaceuticals,and pesticide research.A variety of theoretical frameworks and chiroptical spectroscopic methods,including optical rotation and circular dichroism,have been devised to identify and quantify enantiomers.Generally,circularly polarized light is utilized to determine the absolute configuration and composition of enantiomers.However,these techniques are not suitable for racemic mixtures or substances with minimal optical activity.Herein,we propose that ultraviolet-visible-absorption chiral anisotropy(UV-Vis-ChA)of chiral nanostructured Au particles(CNAPs)can be utilized for enantiomeric discrimination,using amino acids as a model system.The CNAPs,synthesized via a seed-mediated method using chiral glutathione as the symmetry-breaking agent,exhibit a helical nanocubic structure.Upon the addition of amino acid enantiomers to the CNAPs solution,the decrease in the UV-Vis absorbance of CNAPs solution,with varying rates,was induced by enantiomers with different enantiomeric excess(ee)values.The rate constant of absorbance decrease(k_(Δ))was proportional to the ee values,regardless of polarity,size,or chromophore type.It is speculated that the UV-Vis-ChA results from the selective aggregation of CNAPs due to the formation of coordination bonds with enantiomers which is driven by their spin polarizations.This work provides a cost-effective,broad-spectrum,and quantitative approach to enantiomeric discrimination.展开更多
Objective： To establish a method of genomic DNA extraction from whole blood using Fe3O4/Au composite particles as a carrier. Methods： Two crucial conditions （sodium chloride concentration and amount of the magnetic...Objective： To establish a method of genomic DNA extraction from whole blood using Fe3O4/Au composite particles as a carrier. Methods： Two crucial conditions （sodium chloride concentration and amount of the magnetic particles） were optimized and 8 different human whole blood samples were used to purify genomic DNA under the optimal condition. Then agarose gel electrophoresis and polymerase cbain reaction （PCR） were performed. Results： The optimal binding condition was 1.5 mol/L NaC1/10% PEG, and the optimal amount of Fe3O4/Au composite particles was 600μg. The yields of the genomic DNA from 100μl of different whole blood samples were 2-5 μg, and the ratio of A260/A280 was in the range of 1.70-1.90. The size of genomic DNA was about 23 kb and the PCR was valid. Conclusion： The purification system using Fe3O4/Au composite microparticles has advantages in high yield, high purity, ease of operating, time saving and avoiding centrifugation. The purified sample was found to function satisfactorily in PCR amplification.展开更多
The elliptic flow v2, for π±, K±, p and p in Au＋Au collisions at center-of-mass energies √sNN=7.7, 11.5, 14.5 and 19.6 GeV, is analyzed using a multiphase transport model. A significant difference in the ...The elliptic flow v2, for π±, K±, p and p in Au＋Au collisions at center-of-mass energies √sNN=7.7, 11.5, 14.5 and 19.6 GeV, is analyzed using a multiphase transport model. A significant difference in the v2 values for p and p is observed, and the values of v2 splitting are larger compared with π＋ and π-, K＋ and K-. The difference increases with decreasing the center-of-mass energy. The effect of the quark coalescence mechanism in a multi-phase transport model to the value of elliptic difference △v2 between p and p- has been discussed. The simulation of Au＋Au collisions at 14.5 GeV shows that the effect of hadron cascade to △v2 is not obvious, and a larger patton-scattering cross section can lead to a larger △v2.展开更多
Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a kn...Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a known plasmonic material. Semiconductor-metal nanocomposites in isolated, embedded, or encapsulated form, when irradiated with proper light frequency can exhibit localized surface plasmon resonance （LSPR） effect. This effect can result in improved light adsorption and electrical properties of a material. In this study, we report the enhanced visible light photo-response of LSPR induced volatile organic biomarker vapor sensing at room temperature using a Au-embedded TNA electrochemical sensor. Two mechanisms are proposed. One based on classical physics （band theory）, which explains operation under non-irradiated conditions. The second mechanism is based on the coupling of classical and quantum physics （molecular orbitals）, and explains sensor operation under irradiated conditions.展开更多
Oxidative stress is associated with various diseases.Therapeutic strategies targeting redox balance regulations have been tested.However,the lack of knowledge about the heterogeneous metabolism and redox balance withi...Oxidative stress is associated with various diseases.Therapeutic strategies targeting redox balance regulations have been tested.However,the lack of knowledge about the heterogeneous metabolism and redox balance within different regions of tissues limits the development of redox-targeted therapies.In this study,mass spectrometry imagingwas used to profile the redox and metabolic heterogeneity in response to oxidative stress induced by in situ synthesis of Au particles.Our findings showed that the kidney cortex exhibited better glutathione(GSH)-related reducibility than medulla to maintain redox homeostasis.The isocitrate dehydrogenase 1 and glucose-6-phosphate dehydrogenase pathways were primary contributors to the reduced state of nicotinamide adenine dinucleotide phosphate regeneration,assisting in the conversion of oxidized GSH to GSH.In solid tumors,oxidative stress induced infiltration of tumor-associated macrophages and suppressed the proliferation of polymorphonuclear cells,which played a crucial role in maintaining tumor redox homeostasis.Our study provided a new strategy to investigate the spatial metabolomic rewiring in tissues during oxidative challenge.展开更多
基金supported by the National Key R&D Program of China(No.2021YFA1200301,S.A.C.)the National Natural Science Foundation of China(No.21931008,S.A.C.)the Shanghai Pilot Program for Basic Research-Shanghai Jiao Tong University(No.21TQ1400219).
文摘Enantiomeric discrimination plays a crucial role in various scientific domains,including analytical chemistry,chemical biology,pharmaceuticals,and pesticide research.A variety of theoretical frameworks and chiroptical spectroscopic methods,including optical rotation and circular dichroism,have been devised to identify and quantify enantiomers.Generally,circularly polarized light is utilized to determine the absolute configuration and composition of enantiomers.However,these techniques are not suitable for racemic mixtures or substances with minimal optical activity.Herein,we propose that ultraviolet-visible-absorption chiral anisotropy(UV-Vis-ChA)of chiral nanostructured Au particles(CNAPs)can be utilized for enantiomeric discrimination,using amino acids as a model system.The CNAPs,synthesized via a seed-mediated method using chiral glutathione as the symmetry-breaking agent,exhibit a helical nanocubic structure.Upon the addition of amino acid enantiomers to the CNAPs solution,the decrease in the UV-Vis absorbance of CNAPs solution,with varying rates,was induced by enantiomers with different enantiomeric excess(ee)values.The rate constant of absorbance decrease(k_(Δ))was proportional to the ee values,regardless of polarity,size,or chromophore type.It is speculated that the UV-Vis-ChA results from the selective aggregation of CNAPs due to the formation of coordination bonds with enantiomers which is driven by their spin polarizations.This work provides a cost-effective,broad-spectrum,and quantitative approach to enantiomeric discrimination.
基金Supported by the National High Technology Research and Development Program of China (2006AA020705)
文摘Objective： To establish a method of genomic DNA extraction from whole blood using Fe3O4/Au composite particles as a carrier. Methods： Two crucial conditions （sodium chloride concentration and amount of the magnetic particles） were optimized and 8 different human whole blood samples were used to purify genomic DNA under the optimal condition. Then agarose gel electrophoresis and polymerase cbain reaction （PCR） were performed. Results： The optimal binding condition was 1.5 mol/L NaC1/10% PEG, and the optimal amount of Fe3O4/Au composite particles was 600μg. The yields of the genomic DNA from 100μl of different whole blood samples were 2-5 μg, and the ratio of A260/A280 was in the range of 1.70-1.90. The size of genomic DNA was about 23 kb and the PCR was valid. Conclusion： The purification system using Fe3O4/Au composite microparticles has advantages in high yield, high purity, ease of operating, time saving and avoiding centrifugation. The purified sample was found to function satisfactorily in PCR amplification.
基金Supported by the National Natural Science Foundation of China under Grant No U1332125the Program for Innovation Research of Science in Harbin Institute of Technology under Grant No B201408
文摘The elliptic flow v2, for π±, K±, p and p in Au＋Au collisions at center-of-mass energies √sNN=7.7, 11.5, 14.5 and 19.6 GeV, is analyzed using a multiphase transport model. A significant difference in the v2 values for p and p is observed, and the values of v2 splitting are larger compared with π＋ and π-, K＋ and K-. The difference increases with decreasing the center-of-mass energy. The effect of the quark coalescence mechanism in a multi-phase transport model to the value of elliptic difference △v2 between p and p- has been discussed. The simulation of Au＋Au collisions at 14.5 GeV shows that the effect of hadron cascade to △v2 is not obvious, and a larger patton-scattering cross section can lead to a larger △v2.
基金supported in part by NSF-STTR Award#IIP-13211530 subcontracted from Nano Synth Materials and Sensors LLC and Utah Government of Economic Development fundsSupport and facilities provided by the Dawn and Roger Crus Renewable Energy Center
文摘Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a known plasmonic material. Semiconductor-metal nanocomposites in isolated, embedded, or encapsulated form, when irradiated with proper light frequency can exhibit localized surface plasmon resonance （LSPR） effect. This effect can result in improved light adsorption and electrical properties of a material. In this study, we report the enhanced visible light photo-response of LSPR induced volatile organic biomarker vapor sensing at room temperature using a Au-embedded TNA electrochemical sensor. Two mechanisms are proposed. One based on classical physics （band theory）, which explains operation under non-irradiated conditions. The second mechanism is based on the coupling of classical and quantum physics （molecular orbitals）, and explains sensor operation under irradiated conditions.
基金supported by grants from the National Natural Sciences Foundation of China(grant nos.22334007,22304175,21827807,and 22274160)and Chinese Academy of Sciences.
文摘Oxidative stress is associated with various diseases.Therapeutic strategies targeting redox balance regulations have been tested.However,the lack of knowledge about the heterogeneous metabolism and redox balance within different regions of tissues limits the development of redox-targeted therapies.In this study,mass spectrometry imagingwas used to profile the redox and metabolic heterogeneity in response to oxidative stress induced by in situ synthesis of Au particles.Our findings showed that the kidney cortex exhibited better glutathione(GSH)-related reducibility than medulla to maintain redox homeostasis.The isocitrate dehydrogenase 1 and glucose-6-phosphate dehydrogenase pathways were primary contributors to the reduced state of nicotinamide adenine dinucleotide phosphate regeneration,assisting in the conversion of oxidized GSH to GSH.In solid tumors,oxidative stress induced infiltration of tumor-associated macrophages and suppressed the proliferation of polymorphonuclear cells,which played a crucial role in maintaining tumor redox homeostasis.Our study provided a new strategy to investigate the spatial metabolomic rewiring in tissues during oxidative challenge.
