Ultrasensitive visual and colorimetric determination of dopamine based on the prevention of etching of silver nanoprisms by chloride
Ultrasensitive visual and colorimetric determination of dopamine based on the prevention of etching of silver nanoprisms by chloride
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DOI：
10.1007/s00604-016-2024-z
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发表时间：
2017-02-01
影响因子：
5.7
通讯作者：
Li, Zengxi
中科院分区：
文献类型：
--
作者：
Fang, Xian;Ren, Hongxuan;Li, Zengxi
本文报道了一种灵敏、选择性好的血清多巴胺（DA）比色测定法。它是基于在DA存在下，银纳米棱镜（AgNPRs）不被氯离子腐蚀的保护作用。在DA不存在的情况下，由于氯离子的腐蚀，AgNPRs的形状由三角形纳米片变为圆形纳米盘。这伴随着从蓝色到紫色和红色到黄色的逐步颜色变化。结果发现，DA强烈吸附在表面的AgNPRs，从而作为一种保护剂。结果，防止了氯化物的蚀刻，并且不会发生颜色变化。这一发现易于利用设计一种方法，无论是裸眼或紫外-可见分光光度法的DA的光学定量。的AgNPRs的面内偶极表面等离子体激元带的波长偏移是线性相关的DA浓度范围从0.5到100 nM。检测限为0.16 nM（S/N比为3），低于大多数现有方法。尿酸、抗坏血酸和其他共存物质不干扰。该传感器是可重复的和稳定的，并应用于测定DA在加标血清样品中，它给出了回收率范围从97.4%至104.3%。
The authors describe a selective and sensitive colorimetric method for determination of dopamine (DA) in serum. It is based on the protection of silver nanoprisms (AgNPRs) from being etched by chloride ion in the presence of DA. In the absence of DA, the shape of the AgNPRs is changed from triangle nanoplates to round nanodisk due to etching by chloride. This is accompanied by a stepwise color change from blue via purple and red to yellow. It is found that DA is strongly adsorbed on the surface of AgNPRs and thereby acts as a protective agent. As a result, etching by chloride is prevented and the color changes do not occur. This finding ease exploited to design a method for optical quantification of DA with either bare eyes or UV-vis spectrophotometry. The wavelength shift of the in-plane dipole surface plasmon band of the AgNPRs is linearly related to the DA concentration in the range from 0.5 to 100 nM. The detection limit is 0.16 nM (at an S/N ratio of 3) which is lower than that of most existing methods. Uric acid, ascorbic acid and other coexisting species do not interfere. The sensor is reproducible and stable and was applied to the determination of DA in spiked serum samples where it gave recoveries that ranged from 97.4 to 104.3%.