Herein, a fast and visible colorimetric method for bisphenol A (BPA) detection was developed using hemin-functionalized reduced graphene oxide (H–rGO) composites and aptamer. The aptamer can be stably adsorbed on the surface of H–rGO, preventing H–rGO from salt-induced aggregation. However, in the presence of BPA, the aptamer can bind with BPA; this results in the aggregation of H–rGO. Consequently, the supernatant contains a little H–rGO and shows light blue color after the chromogenic reaction. The color difference can be used for the quantitative detection of BPA. The designed aptasensor displayed a linear response for BPA in the range from 5 nM to 100 nM with a detection limit of 2 nM. This colorimetric aptasensing platform offered great advantages, including label-free conditions and visible result readout platform, for quick screening of BPA for on-site analysis and in-house diagnosis.

中文翻译：

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基于血红素-石墨烯复合物和适体的过氧化物酶样活性，目测双酚A †

在此，使用血红素功能化的还原氧化石墨烯（H–rGO）复合材料和适体开发了一种快速，可见比色法检测双酚A（BPA）的方法。适体可以稳定地吸附在H–rG​​O的表面上，从而防止H–rGO受到盐诱导的聚集。但是，在存在BPA的情况下，适体可以与BPA结合。这导致了H–rGO的聚集。因此，上色液中含有少量的H–rGO，在显色反应后显示淡蓝色。色差可用于BPA的定量检测。设计的适体传感器对BPA的线性响应范围为5 nM至100 nM，检测极限为2 nM。该比色适体平台具有很大的优势，包括无标签条件和可见结果读出平台，