کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
866954 | 1470984 | 2013 | 8 صفحه PDF | دانلود رایگان |

• We introduced a new impedimetric immunoassay for the detection of low-abundance proteins.
• Enzymatic biocatalytic precipitation of insoluble products was formed.
• Graphene oxide nanosheets were used as labels.
A new sandwich-type impedimetric immunosensor based on functionalized graphene oxide nanosheets with a high ratio of horseradish peroxidase (HRP) and detection antibody was developed for the detection of carcinoembryonic antigen (CEA) by coupling with enzymatic biocatalytic precipitation of 4-chloro-1-naphthol (4-CN) on the captured antibody-modified glassy carbon electrode. Two molecular tags (with and without the graphene oxide nanosheets) were investigated for the detection of CEA and improved analytical features were acquired with the graphene-based labeling. With the labeling method, the performance and factors influencing the properties of the impedimetric immunosensors were also studied and evaluated. Under the optimal conditions, the dynamic concentration range of the impedimetric immunosensors spanned from 1.0 pg mL−1 to 80 ng mL−1 CEA with a detection limit (LOD) of 0.64 pg mL−1. Intra- and inter-assay coefficients of variation were less than 7.5% and 11%, respectively. Additionally, the methodology was evaluated for CEA analysis of 10 clinical serum samples and 5 diluted serum samples, receiving in a good accordance with the results obtained by the impedimetric immunoassay and the commercialized electrochemiluminescent method.
Journal: Biosensors and Bioelectronics - Volume 47, 15 September 2013, Pages 149–156