A Label-Free Colorimetric Assay Based on Gold Nanoparticles for the Detection of H2O2 and Glucose

Cong Zheng,Da Wu,Tao Wang,Jianhong Xiao,Li Yu

doi:10.3390/chemosensors10030100

Abstract

The significance of sensing hydrogen peroxide (H2O2) is due to its ubiquity, being a potential biomarker as well as an end-product of several oxidation reactions. Herein, based on gold nanoparticles (AuNPs) and coupled with single-stranded DNA (ssDNA) and ceria nanoparticles (CeO2), we developed a novel colorimetric method to detect H2O2 and glucose in NaCl solutions. In the presence of H2O2, ssDNA adsorbed on the surface of CeO2 could be released and subsequently decorated AuNPs, resulting in a distinct color change of the aqueous solution from purple to red, which could be observed by the naked eye. Since H2O2 can be produced in the process of glucose oxidation by glucose oxidase (GOx), this approach can also be employed to detect glucose. By employing this sensing system, the detection limits for H2O2 and glucose are about 0.21 μM and 3.01 µM, respectively. Additionally, monitoring the content of glucose in blood serum samples was successfully achieved by the proposed strategy. This work opens a potential avenue for the quantitative detection of H2O2 and glucose in clinical diagnostics.

Highlights

The significance of sensing hydrogen peroxide (H2 O2 ) is due to its ubiquity, being a potential biomarker as well as an end-product of several oxidation reactions
H2 O2 is the final product in oxidation reactions and is catalyzed by glucose oxidase (GOx), cholesterol oxidase, and lactate oxidase, etc. [4,5]
These results suggest that AuNPs aggregation could occur in system as CeO2 was modified by single-stranded DNA (ssDNA) due to the coordination interaction between the ssDNA backbone and CeO2 [48]

Summary

Introduction

The significance of sensing hydrogen peroxide (H2 O2 ) is due to its ubiquity, being a potential biomarker as well as an end-product of several oxidation reactions. Based on gold nanoparticles (AuNPs) and coupled with single-stranded DNA (ssDNA) and ceria nanoparticles (CeO2 ), we developed a novel colorimetric method to detect H2 O2 and glucose in NaCl solutions. Since H2 O2 can be produced in the process of glucose oxidation by glucose oxidase (GOx), this approach can be employed to detect glucose. Nanomaterials have gained much attention in colorimetric biosensing and diagnostics on account of their unique physical or chemical properties [10–17]. Some nanomaterials such as graphene quantum dots (GQDs)/AgNPs hybrids and Pt nanoclusters [5,18] have been synthesized for the colorimetric detection of H2 O2 , but they generally require complex synthesis procedures or time-consuming operations. It possesses the ability to absorb ssDNA [10,19–22]

Methods

Results

Conclusion