Monolayer graphene oxide-Au loaded compound (GO-Au) as a flexible, stable and sensitive SERS active substrate for detection of stonehouse clam toxin (STX)

Abstract

Stonehouse clam toxin (STX) is a prevalent neuroparalytic toxin found among shellfish toxins. When consumed by humans, it disrupts neuronal conduction, potentially leading to quadriplegia, headache, shock, and even respiratory failure-induced death. This study introduces a highly sensitive and specific method for detecting shellfish toxins. The approach involves utilizing graphene gold-loaded compounds alongside stone house clam toxin aptamers and their complementary chains. The layered structure of graphene creates numerous hot spots among nanoparticles, while its arched spatial configuration offers an enhanced specific surface area, resulting in improved Surface-Enhanced Raman Scattering (SERS). By combining the signaling molecule Bodipy R6G-modified Apt with GO-Au loading compounds, distinctive Raman characteristic peaks emerge. Due to the strong affinity between Apt and STX, the Apt carrying the signaling molecule migrates away from the SERS aptamer probe's surface, thereby attenuating the original SERS signal intensity and facilitating ultra-sensitive shellfish toxin detection. The detection limit for the toxin was determined to be 5.47 nM, with a recovery rate ranging from 97.60 % to 108.32 %, affirming the applicability of this design for quantitative and specific shellfish toxin detection, signifying its considerable practical significance.