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Glucose oxidase-catalyzed growth of gold nanoparticles enables quantitative detection of attomolar cancer biomarkers.

Liu D, Yang J, Wang HF, Wang Z, Huang X, Wang Z, Niu G, Hight Walker AR, Chen X - Anal. Chem. (2014)

Bottom Line: 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.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.

View Article: PubMed Central - PubMed

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.

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.

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Schematic Diagramof the Quantitative Immunoassay Based on GlucoseOxidase (GOx)-Catalyzed Growth of Gold Nanoparticles (AuNPs, 5 nmin Diameter)Prostate-specific antigen(PSA) is first immobilized by the capture antibody (Ab1) and thenrecognized by the detection antibody (Ab2) conjugated with GOx onthe surfaces of magnetic beads (MBs). The immobilized GOx catalyzesthe oxidation of β-d-glucose to generate H2O2, which induces the growth of the 5 nm AuNPs in thepresence of AuCl4–. With the enlargementof AuNPs, the solution turns red from colorless.
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sch1: Schematic Diagramof the Quantitative Immunoassay Based on GlucoseOxidase (GOx)-Catalyzed Growth of Gold Nanoparticles (AuNPs, 5 nmin Diameter)Prostate-specific antigen(PSA) is first immobilized by the capture antibody (Ab1) and thenrecognized by the detection antibody (Ab2) conjugated with GOx onthe surfaces of magnetic beads (MBs). The immobilized GOx catalyzesthe oxidation of β-d-glucose to generate H2O2, which induces the growth of the 5 nm AuNPs in thepresence of AuCl4–. With the enlargementof AuNPs, the solution turns red from colorless.


Glucose oxidase-catalyzed growth of gold nanoparticles enables quantitative detection of attomolar cancer biomarkers.

Liu D, Yang J, Wang HF, Wang Z, Huang X, Wang Z, Niu G, Hight Walker AR, Chen X - Anal. Chem. (2014)

Schematic Diagramof the Quantitative Immunoassay Based on GlucoseOxidase (GOx)-Catalyzed Growth of Gold Nanoparticles (AuNPs, 5 nmin Diameter)Prostate-specific antigen(PSA) is first immobilized by the capture antibody (Ab1) and thenrecognized by the detection antibody (Ab2) conjugated with GOx onthe surfaces of magnetic beads (MBs). The immobilized GOx catalyzesthe oxidation of β-d-glucose to generate H2O2, which induces the growth of the 5 nm AuNPs in thepresence of AuCl4–. With the enlargementof AuNPs, the solution turns red from colorless.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4066917&req=5

sch1: Schematic Diagramof the Quantitative Immunoassay Based on GlucoseOxidase (GOx)-Catalyzed Growth of Gold Nanoparticles (AuNPs, 5 nmin Diameter)Prostate-specific antigen(PSA) is first immobilized by the capture antibody (Ab1) and thenrecognized by the detection antibody (Ab2) conjugated with GOx onthe surfaces of magnetic beads (MBs). The immobilized GOx catalyzesthe oxidation of β-d-glucose to generate H2O2, which induces the growth of the 5 nm AuNPs in thepresence of AuCl4–. With the enlargementof AuNPs, the solution turns red from colorless.
Bottom Line: 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.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.

View Article: PubMed Central - PubMed

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.

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.

Show MeSH
Related in: MedlinePlus