Dual‐spectroscopic real‐time monitoring of the reduction reaction between aristolochic acid I and Fe2+ and its bio‐application

Abstract Aristolochic acid (AA) is widely present in herbal medicine. Aristolochic acid I (AAI) and aristolochic acid lactam (AAT), as the main active ingredients in AAs, have serious nephrotoxicity, strong carcinogenicity, and mutagenicity. AAT is a metabolite of AAI in the human body. AAI can be reduced by Fe 2+ both in the human body and soil. A new dual spectrum is proposed to monitor the reaction directly from the human protein serum (HAS) and A549 cells through surface‐enhanced Raman spectroscopy (SERS) and its biological product AAT through fluorescence detection (FLD) spectra based on its unique spectral response. In order to better monitor the reduction reaction, the AAI detection conditions are optimized, including concentration, pH, reducing agent, and reaction time. During the experiment, Ag@Au is selected as the SERS substrate. Moreover, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the prepared SERS support substrate. CCK‐8 assays showed that the viability of cells decline after adding AAI. Fe 2+ was found to detect AAI in endogenous A 549 cells.