Development of Nanoparticle Probes for Molecular Imaging

金和银纳米颗粒在生物和化学纳米传感器中的应用越来越受到关注。制备了酰胺功能化的金纳米粒子（Amide Au-NP）。用紫外-可见滴定法研究了酰胺金纳米粒子的阴离子传感性能。在20℃下，在0-1%DMSO/CH_2Cl_2的酰胺金-NP溶液中加入阴离子，引起等离子体激元带的显著变化。消光的显著降低是由于酰胺Au-NP的阴离子诱导的聚集。Δl_<max>=（l_<min>- l_0）/（l_0）与阴离子在气相中的水合自由能ΔG_<0.1>（kcal mol）<-1>作图，作为客体阴离子氢键受体强度的量度。阴离子的Δl_<max>与ΔG^o_<0.1>之间有很好的相关性。对HSO_4^-和H_2PO_4^-的选择性较其它阴离子强，表明NHCO与H_2PO_4的氢键作用较强。HOX（X=S或P）显著地有助于阴离子识别，导致纳米颗粒聚集。据指出， ...更多信息 酰胺Au-NP能够在10 μ M的水平上光学感测阴离子浓度的变化<-6>。以1-硫代-β-D-葡萄糖（1-TG）为还原剂和封端剂，通过化学还原HAuCl 4制备了硫代葡萄糖封端的金纳米粒子（1-TG Au-NP）。1-TG Au-NP在生理pH的缓冲溶液中能很好地分散，在20℃下，在10 mM HEPES缓冲溶液（pH 7.4）中，用紫外可见分光光度法研究了卤素阴离子和含氧阴离子的比色检测。在1-TG Au-NP溶液中加入F^-会导致表面等离子体带的红移。在高于600 nm的波长处的消光对应于紧密间隔的金纳米颗粒的集体等离子体共振，表明阴离子诱导的纳米颗粒聚集。DLS测量还表明，在添加阴离子后，1-TG Au-NP的尺寸分布从30 nm变化到100 nm。1-TG Au-NP显示出对F^-的选择性聚集超过其他阴离子。F ^-的强碱性可以解释F^-优于其他阴离子的原因。少

Gold and silver nanoparticles have been of increasing interest in applications to biological and chemical nanosensors. Amide-functionalized gold nanoparticles (Amide Au-NP) have been prepared. The anion sensing properties of Amide Au-NP were investigated by UV-vis titrations. The addition of anions to a solution of Amide Au-NP in 0-1%DMSO/CH_2Cl_2 at 20℃ caused dramatic changes in the plasmon band. The marked decrease in extinction is due to anion-induced aggregation of Amide Au-NP. Δl_<max>=(l_<min> - l_0)/ (l_0 is plotted against the free energy of hydration ΔG^o_<0.1>(kcal mol^<-1>) in the gas phase for the anions as a measure of hydrogen-bond acceptor strength of the guest anions. There is a good correlation between Δl_<max> and ΔG^o_<0.1> for the anions. The preference for HSO_4^- and H_2PO_4^- over other anions indicates that the hydrogen-bond interaction of NHCO...HOX (X=S or P) significantly contributes to the anion recognition leading to nanoparticle aggregation. It is noted t … More hat the Amide Au-NP are capable of optically sensing changes in anion concentration at a level of 10^<-6>M. The detection limit is increased about three orders of magnitude higher than originally expected.Thioglucose-capped gold nanoparticles (1-TG Au-NP) have been prepared by the chemical reduction of HAuCl4 using 1-thio-β-D-glucose (1-TG) as the reducing and capping agent. The 1-TG Au-NP could be well dispersed in the buffer solution at physiological pH. The colorimetric detection of halide anions and oxoanions was investigated using UV-vis spectroscopy in an aqueous solution of 10 mM HEPES buffer (pH 7.4) at 20℃. Addition of F^- to a solution of the 1-TG Au-NP causes a red shift in the surface plasmon band. Extinction at wavelengths above 600 nm corresponds to the collective plasmon resonance of closely spaced gold nanoparticles, indicating the anion-induced nanoparticle aggregation. DLS measurements also indicate the size distribution of the 1-TG Au-NP change from 30 nm to 100 nm upon the addition of anions. The 1-TG Au-NP shows selective aggregation for F^- over other anions. The preference for F^- over other anions can be explained by the strong basicity of F^-. Less