采用β-环糊精作为还原剂和稳定剂对金纳米粒子进行功能化，当溶液中有铅离子存在时，会导致功能化金纳米粒子的聚集，体系颜色发生变化，从而实现对铅离子残留的比色检测。研究结果表明，伴随Pb²⁺浓度的提高，体系颜色由淡红色转变为蓝色或紫色；紫外-可见光光谱分析结果表明，当铅离子浓度处于0.01~2 000 μmol/L时，R²值为0.983 2，工作曲线方程为y=-31.457 3x+6.398 4，最低检测限为8.98 μmol/L；该检测体系稳定且有优异的重复性，并对4种常见氨基酸和3种常见金属离子具有明显的抗干扰性能。

β-Cyclodextrin is used as reductant and stabilizer to functionalize gold nanoparticles.If lead ions exist in a solution,which can lead to the aggregation of β-CD-AuNPs and therefore the color of the system changes,and the targeted detection of lead ions can be realized.It is demonstrated that a red-to-blue color change can be observed in the solution with the increasing Pb²⁺ concentration.The results by UV-Vis spectrum indicate that R² value is 0.983 2 and the working curve equation is y=-31.457 3x+6.398 4 when Pb²⁺ concentration is in the range of 0.01-2 000 μmol·L^-1.The detection limit is 8.98 μmol·L^-1.Additionally,the proposed colorimetric method exhibits excellent repeatability and shows significant anti-interference performance against 4 kinds of common amino acids and 3 kinds of common metal ions.