中文摘要：

目的采用金纳米棒作为探针,构建一套灵敏简单的用于检测维生素C的比色方法。方法采用壳聚糖-三聚磷酸钠复合物作为还原剂和稳定剂制备金纳米棒;采用紫外-可见光分光光度计和透射电子显微镜对其进行表征;根据金汞齐的形成原理,通过金纳米棒的长短径比值下降所造成的溶液颜色的明显变化,快速检测体系中不同浓度的维生素C。结果当检测体系中出现维生素C时,颜色由蓝色变为橙色;在维生素C浓度为1~100μmol/L和250—2000μmol/L范围内时,其浓度与体系吸光度比值（A_（530）/A_（640））呈现明显的线性关系,相关系数分别为0.9894和0.9843,检出限为0.067μmol/L。结论该体系下制备的金纳米比色探针可以实时快速检测维生素C的含量。

英文摘要：

Objective To establish a sensitive and simple colorimetric method for determination of vitamin C（Vc） based on the gold nanorods（AuNRs）.Methods AuNRs were prepared by reducing gold salt with chitosan,in the presence of tripolyphosphate（TPP）.Chitosan-TPP was acted as a reducing/stabilizing agent.The obtained AuNRs were characterized with UV-Vis spectroscopy and transmission electron microscopy.The decreased of the aspect ratio（length/width） of AuNRs led to a color change in the presence of vitamin C at different concentrations based on forming goldmalgam.Results The color of detection system changed from blue to red in the presence of vitamin C.The absorbance ratio（A_（530）/A_（640）） was linear with the Vc concentration in the range of 1~100 umol/L and 250~2000umol/L,with the correlation coefficients of 0.9894 and 0.9843,respectively.The limit of detection was 0.067 μmol/L.Conclusion The reported gold nanoparticles colorimetric probe is suitable for real-time detection of Vc.