A Label-free Immunosensor for Microcystins-LR Based on Graphene and Gold Nanocage
10.3724/SP.J.1096.2014.30666
- VernacularTitle:基于石墨烯和金纳米笼修饰的无标记型微囊藻毒素免疫传感器的研制
- Author:
Huali DU
;
Xuewen FU
;
Yongping WEN
;
Zejun QIU
;
Limei XIONG
;
Nianzhang HONG
;
Yunhui YANG
- Publication Type:Journal Article
- Keywords:
Microcystin;
Graphene;
Gold nanocage;
Label-free immunosensor
- From:
Chinese Journal of Analytical Chemistry
2014;(5):660-665
- CountryChina
- Language:Chinese
-
Abstract:
A label-free electrochemical immunosensor using hollow structure nanomaterials based on its ordered porous and big surface area was designed. Au nanocage, with good conductivity, catalysis, and biocompatibility, was prepared and modified on the surface of glassy carbon electrode with graphene to immobilize antibody of microcystin directly. In the absence of microcystin, biosensor can obtain high current response signal of electrochemical probe ( [ Fe( CN) 6 ] 3-/4-. When microcystin was combined with its antibody specifically, the charge density and mass transfer resistance on the surface of electrode increased, resulting in a decrease of the corresponding peak current of [ Fe ( CN ) 6 ] 3-/4-. This change was in proportion to the concentration of microcystin indirectly. Experiment conditions such as cultivation time of antigen and concentration of antibody were optimized. The results showed wide linear range of 0. 05 μg/L-1. 0 mg/L and the detection limit of 0. 017 ng/mL. This sensor has good stability and simple production procedure. This sensor provides a new and simple means for the ultrasensitive determination of microcystins in real water samples.
