Glucose Oxidase-Catalyzed Growth of Gold Nanoparticles Enables Quantitative Detection of Attomolar Cancer Biomarkers

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• 作者：Dingbin Liu ; Jie Yang ; He-Fang Wang ; Zhongliang Wang ; Xinglu Huang ; Zhantong Wang ; Gang Niu ; A. R. Hight Walker ; Xiaoyuan Chen
• 刊名：Analytical Chemistry
• 出版年：2014
• 出版时间：June 17, 2014
• 年：2014
• 卷：86
• 期：12
• 页码：5800-5806
• 全文大小：356K
• 年卷期：v.86,no.12(June 17, 2014)
• ISSN：1520-6882

文摘

Ultrasensitive and quantitative detection of cancer biomarkers is an unmet challenge because of their ultralow concentrations in clinical samples. Although gold nanoparticle (AuNP)-based immunoassays offer high sensitivity, they were unable to quantitatively detect targets of interest most likely due to their very narrow linear ranges. This article describes a quantitative colorimetric immunoassay based on glucose oxidase (GOx)-catalyzed growth of 5 nm AuNPs that can detect cancer biomarkers from attomolar to picomolar levels. In addition, the limit of detection (LOD) of prostate-specific antigen (PSA) of this approach (93 aM) exceeds that of commercial enzyme-linked immunosorbent assay (ELISA) (6.3 pM) by more than 4 orders of magnitude. The emergence of red or purple color based on enzyme-catalyzed growth of 5 nm AuNPs in the presence of target antigen is particularly suitable for point-of-care (POC) diagnostics in both resource-rich and resource-limited settings.