摘要
金纳米颗粒(AuNPs)具有独特的等离子体共振吸收性质.半胱氨酸与金纳米颗粒之间的Au-S共价键作用导致金纳米颗粒等离子体共振吸收红移,本文据此建立了一种通用性的氧化性小分子的可视化分析方法.当氧化性小分子如H2O2或者单线态氧(1O2)存在时,半胱氨酸的巯基被氧化成-S-S-键,使半胱氨酸诱导金纳米颗粒聚集的能力降低,从而金纳米颗粒的等离子体共振吸收峰由740nm蓝移到531nm,溶液颜色逐渐由蓝变红,据此实现了氧化性小分子的可视化检测.研究发现,740和531nm处的吸收度比值(A740/A531)与H2O2或者1O2的浓度呈现良好的线性关系.将所建立的方法用于老鼠脑浆中H2O2的检测,检测结果与流动注射-化学发光法一致.
Gold nanoparticles (AuNPs) have the unique property of plasmon resonance absorption (PRA). In this contribution, universal colorimetric detection of oxidants was achieved using cysteine induced AuNPs aggregation, which leads to a red-shift of in the PRA. The SH group of a cysteine molecule can be oxidized into a -S-S- bond in the presence of oxidants such as H202 or 1^O2, which leads to reduced aggregation in the AuNPs. These blue-shifts of the PRA from 740 nm to 531 rim, and results in a blue-to-red color change. It was found that the ratio of absorbance at 740 nm to that at 531 nm (A74dA53D was in proportion to the concentrations of H202 and Io2. Also, this colorimetric method can be successfully applied to detecting H202 in rat brains, which offers performance similar to flow injection-chemiluminescence.
出处
《科学通报》
EI
CAS
CSCD
北大核心
2011年第15期1196-1203,共8页
Chinese Science Bulletin
基金
国家自然科学基金重大研究计划资助项目(90813019)