College of Food Science and Technology, Yunnan Agricultural University, Kunming 650500, Yunnan, PR China.
Key Laboratory of Natural Products Synthetic Biology of Ethnic Medicinal Endophytes, Yunnan Minzu University, Kunming 650500, Yunnan, PR China.
Food Chem. 2024 Oct 30;456:139955. doi: 10.1016/j.foodchem.2024.139955. Epub 2024 Jun 3.
The nanozyme-linked aptamer-sorbent assay (NLASA) is a rapid way to screen and characterize aptamer binding to targets. In this paper, a MnO@AuNPs@aptamer (Apt) based NLASA coupled with colorimetric-SERS dual-mode for Staphylococcus aureus (S. aureus) detection is presented. Cu,Fe-CDs were used as the reducing agent to synthesize MnO and gold nanoparticles (AuNPs). Then, they were fabricated to obtain MnO@AuNPs with oxidase (OXD)-like and SERS activities. The S. aureus aptamer was conjugated to MnO@AuNPs and enhanced the OXD-like activity, which realized the specific capture of S. aureus in food matrices. In addition, S. aureus improves the oxidation of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid (ABTS) but inhibits 3,3',5,5'-tetramethylbenzidine (TMB) to generate Raman-active oxTMB with MnO@AuNPs@Apt. This sensor was used for detections of S. aureus in a concentration ranged from 10 to 10 CFU/mL with a detection limit of 0.926 CFU/mL (colorimetric) and 1.561 CFU/mL (SERS), and the recovery is 85%-105% in real samples.
纳米酶连接适体吸附分析（NLASA）是一种快速筛选和表征适体与靶标结合的方法。本文提出了一种基于 MnO@AuNPs@aptamer（Apt）的 NLASA 与比色-SERS 双模结合，用于金黄色葡萄球菌（S. aureus）检测。Cu，Fe-CDs 被用作还原剂来合成 MnO 和金纳米粒子（AuNPs）。然后，它们被制备以获得具有氧化酶（OXD）样和 SERS 活性的 MnO@AuNPs。S. aureus 适体与 MnO@AuNPs 偶联，增强了 OXD 样活性，实现了食品基质中 S. aureus 的特异性捕获。此外，S. aureus 提高了 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）的氧化，但抑制了 3,3',5,5'-四甲基联苯胺（TMB），用 MnO@AuNPs@Apt 生成拉曼活性的 oxTMB。该传感器用于检测浓度范围为 10 至 10 CFU/mL 的 S. aureus，检测限为 0.926 CFU/mL（比色法）和 1.561 CFU/mL（SERS），在实际样品中的回收率为 85%-105%。
