Enhanced Nanozymatic Activity on Rough Surfaces for H2O2 and Tetracycline Detection

Abstract

The needless use of tetracyclines (TCs) in foodstuffs is a huge health concern in low- and middle-income and Arab countries. Herein, a sensitive and faster monitoring system for H2O2 and TCs is proposed, utilizing the large surface-to-volume ratio of a non-spherical gold nanoparticle/black phosphorus nanocomposite (BP-nsAu NPs) for the first time. BP-nsAu NPs were synthesized through a single-step method that presented nanozymatic activity through 3,3′,5,5′-Tetramethylbenzidine (TMB) oxidation while H2O2 was present and obeyed the Michaelis–Menten equation. The nanozymatic activity of the BP-nsAu NPs was enhanced 12-fold and their detection time was decreased 83-fold compared to conventional nanozymatic reactions. The proposed method enabled us to quantify H2O2 with a limit of detection (LOD) value of 60 nM. Moreover, target-specific aptamer-conjugated BP-nsAu NPs helped us detect TCs with an LOD value of 90 nM. The present strategy provides a proficient route for low-level TC monitoring in real samples.

Synthesis of β-Cyclodextrin@gold Nanoparticles and Its Application on Colorimetric Assays for Ascorbic Acid and Salmonella Based on Peroxidase-like Activities

“…The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/bios14040169/s1, Figure S1: Optimization of CD@AuNPs synthesis; Figure S2: Optimization of β-CD@AuNPs on peroxidase-like activity performances; Figure S3: Influences on the peroxidase-like performances of β-CD@AuNPs; S1: 1 H NMR Chemical shifts of β-CD and β-CD@AuNPs; Table S2: Kinetic parameters of peroxidase-like activity of β-CD@AuNPs.…”

“…Gold nanoparticle (AuNPs)-based colorimetric assays are of great interest for the identification of chemical compounds and biological contamination in the fields of food and environmental monitoring and biomedical applications [1]. AuNPs, normally with a diameter of 1~100 nm, possess localized surface plasmon resonance (LSPR) character, excellent conductivity and specific molecular recognition via their surface electrostatic adsorption or labeled with desirable antibodies or aptamers [2,3].…”