The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2?] self-assem...The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2?] self-assembles on the surface of positively-charged gold nanopar-ticle, which results in the [(Au)n(H2L)m]x? complex. In other words, one of carboxylate oxygens in (H2L)2? moves inward and combines with gold nanoparticle. The other carboxylate oxygens moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with ST cation to form a new ion-association complex. Here (H2L)2? acts as a bridge. The forma-tion of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasma absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for safranine T. In this work, the inter-action between gold nanoparticle and ST on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectra can not only be used to study nanopar-ticle and reaction product, but also are a sensitive means to characterize and detect nanoparti-cles.展开更多
通过紫外吸收光谱法、紫外二阶导数光谱法和荧光光谱法研究了生理pH值条件、紫外照射(UV C 253.7nm)下Pb(Ⅱ)与牛血清白蛋白(BSA)的相互作用。紫外光谱和紫外二阶导数光谱显示紫外光照射改变了蛋白质中氨基酸残基的微环境。Stern-Volme...通过紫外吸收光谱法、紫外二阶导数光谱法和荧光光谱法研究了生理pH值条件、紫外照射(UV C 253.7nm)下Pb(Ⅱ)与牛血清白蛋白(BSA)的相互作用。紫外光谱和紫外二阶导数光谱显示紫外光照射改变了蛋白质中氨基酸残基的微环境。Stern-Volmer方程和Lineweaver-Burk方程分析表明,经紫外光照射后,Pb(Ⅱ)对BSA的荧光猝灭作用依然为静态猝灭作用,且没有改变其强结合位点的位置。受紫外照射过的BSA加入Pb(Ⅱ)后,BSA与Pb(Ⅱ)的结合常数(KS)随着照射时间的延长而逐渐降低;而BSA与Pb(Ⅱ)先混合后照射时,结合常数(KS)随着照射时间的延长却逐渐升高。展开更多
The interaction of silver? ion with lysine has been investigated by UV?鄄Vis, fluorescent spectra and electrophoresis method. The effect of pH medium and multicomponent concentration on interaction of lysine-silver ha...The interaction of silver? ion with lysine has been investigated by UV?鄄Vis, fluorescent spectra and electrophoresis method. The effect of pH medium and multicomponent concentration on interaction of lysine-silver has also been studied. Lysine-silver system showed maximum absorbance at 239 nm and 448 nm. Lysine showed fluorescence. The fluorescence excitation wavelength was about 356.6 nm (fluorescence emission wavelength was about 438.6 nm). When the reaction of silver? ion with lysine happened, fluorescence was quenching. Lysine-silver system carried negative charge, and the electrokinetic potential of double electrode layer was -2.35×10-4 V.展开更多
基金the National Natural Science Foundation of China(Grant No.20175018).
文摘The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2?] self-assembles on the surface of positively-charged gold nanopar-ticle, which results in the [(Au)n(H2L)m]x? complex. In other words, one of carboxylate oxygens in (H2L)2? moves inward and combines with gold nanoparticle. The other carboxylate oxygens moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with ST cation to form a new ion-association complex. Here (H2L)2? acts as a bridge. The forma-tion of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasma absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for safranine T. In this work, the inter-action between gold nanoparticle and ST on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectra can not only be used to study nanopar-ticle and reaction product, but also are a sensitive means to characterize and detect nanoparti-cles.
文摘通过紫外吸收光谱法、紫外二阶导数光谱法和荧光光谱法研究了生理pH值条件、紫外照射(UV C 253.7nm)下Pb(Ⅱ)与牛血清白蛋白(BSA)的相互作用。紫外光谱和紫外二阶导数光谱显示紫外光照射改变了蛋白质中氨基酸残基的微环境。Stern-Volmer方程和Lineweaver-Burk方程分析表明,经紫外光照射后,Pb(Ⅱ)对BSA的荧光猝灭作用依然为静态猝灭作用,且没有改变其强结合位点的位置。受紫外照射过的BSA加入Pb(Ⅱ)后,BSA与Pb(Ⅱ)的结合常数(KS)随着照射时间的延长而逐渐降低;而BSA与Pb(Ⅱ)先混合后照射时,结合常数(KS)随着照射时间的延长却逐渐升高。
文摘The interaction of silver? ion with lysine has been investigated by UV?鄄Vis, fluorescent spectra and electrophoresis method. The effect of pH medium and multicomponent concentration on interaction of lysine-silver has also been studied. Lysine-silver system showed maximum absorbance at 239 nm and 448 nm. Lysine showed fluorescence. The fluorescence excitation wavelength was about 356.6 nm (fluorescence emission wavelength was about 438.6 nm). When the reaction of silver? ion with lysine happened, fluorescence was quenching. Lysine-silver system carried negative charge, and the electrokinetic potential of double electrode layer was -2.35×10-4 V.
