建立了一种基于非标记金纳米粒子快速比色检测L-半胱氨酸的方法。采用废弃葡萄皮的提取物制备金纳米粒子，并对其表观形貌、稳定性和催化特性进行表征。再利用所制备的金纳米粒子比色检测不同浓度的L-半胱氨酸，并构建工作曲线。结果表明，葡萄皮提取物所制备金纳米粒子粒径均匀，且具有良好的稳定性和催化活性；在0.01~1 μmol/L和5~100 μmol/L范围内半胱氨酸浓度与吸光度比值（A₅₃₉/A₈₆₃）具有较为明显的线性关系，检出限为0.837 μg/L（S/N）。该类型金纳米粒子比色检测体系对半胱氨酸具有良好的选择性和灵敏度。

A colorimetric detection method for L-cysteine method is established based on the label-free gold nanoparticles (AuNPs) that are prepared from waste grape peel extract.The apparent morphology,stability and catalytic properties of the gold nanoparticles are characterized.AuNPs are used to detect L-cysteine at different concentrations to construct the working curve.The results show that AuNPs prepared by grape peel extract have even particle size,good stability and catalytic activity.The absorbance ratio (A₅₃₉/A₈₆₃) shows linear with L-cysteine concentration in the ranges of 0.01-1 μmol·L^-1 and 5-100 μmol·L^-1,with a detection limit of 0.837 μg·L^-1 (S/N).This type of AuNPs colorimetric detection method has a good selective and sensitive to L-cysteine.