Dual-signal histamine aptasensor design based on SERS and electrochemical effects of gold nanomaterials

A dual signal (Raman/electrochemical) and selective assay for determination of histamine (HA) was developed by leveraging the surface-enhanced Raman and electrochemical enhancement effects of gold nanomaterials and the high specificity of aptamers. Gold nanorods probes co-modified with the Raman reporter molecule 4-MBA and HA aptamers were prepared. Simultaneously, gold nanoparticles were electrodeposited onto ITO, and complementary DNA strands were immobilized to form an electrochemical signal substrate. The two parts assembled based on complementary base pairing. With the addition of HA, aptamers preferentially combined to HA and the assembly disrupted, leading to synchronous decreases in Raman and electrochemical signals. The results demonstrated a linear relationship between the logarithmic values of HA concentration (0.1-1000 mg/L) and the dual signals, with a detection limit as low as 0.015 mg/L. Furthermore, its application in fish yielded satisfactory spiked recoveries (92.6%-94.5%), confirming its reliability in real food analysis. The method not only enhances detection reliability and anti-interference capabilities but also enables precise identification of trace HA. Potential applications of the method extend beyond HA detection, offering a versatile platform for food safety monitoring and public health protection.