title: Glucose oxidase-catalyzed growth of gold nanoparticles enables quantitative detection of attomolar cancer biomarkers.
abstract: 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.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Collaborative Innovation Center of Chemical Science and Engineering, and Research Center for Analytical Sciences, College of Chemistry, Nankai University , Tianjin, China.
authors.forename: Dingbin
authors.initials: D
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: He-Fang
authors.initials: HF
authors.lastname: Wang
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Wang
authors.forename: Xinglu
authors.initials: X
authors.lastname: Huang
authors.forename: Zhantong
authors.initials: Z
authors.lastname: Wang
authors.forename: Gang
authors.initials: G
authors.lastname: Niu
authors.forename: A R
authors.initials: AR
authors.lastname: Hight Walker
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Chen
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002384:Catalysis; D004797:Enzyme-Linked Immunosorbent Assay; D005949:Glucose Oxidase / Q000378:metabolism*; D006046:Gold / Q000737:chemistry*; D007118:Immunoassay; D057230:Limit of Detection; D053768:Metal Nanoparticles; D046529:Microscopy, Electron, Transmission
chemical_list: D014408:Biomarkers, Tumor; D006046:Gold; D005949:Glucose Oxidase