Multifunctional integration of large-pore dendritic mesoporous silica nanospheres and highly conductive graphene nanoplates for ultrasensitive electrochemical detection of trace gallic acid

A novel multifunctional electrochemical sensing electrode sensitizer was designed by integrating the highly conductive graphene nanoplates (CGNP) with large-pore dendritic mesoporous silica nanospheres (DMPS), which was first utilized to construct the gallic acid (GA) electrochemical sensing platform (DMPS@CGNP/GCE). DMPS with large-pore dendritic structure provided abundant internal pore connectivity and material transport channels, increased specific surface area, and expanded pore volume, which presented abundant adsorption sites, significantly improving the enrichment capacity for GA molecules. CGNP with ultra-high purity and few layers presented remarkable conductivity property coupled with exceptionally expansive specific surface area and more electrochemical active sites. The synergistic effect of DMPS@CGNP promoted the interface electron transfer, thereby significantly improving the sensitivity of GA detection. The DMPS@CGNP/GCE platform achieved the ultrasensitive electrochemical analysis of trace GA with low detection of limit of 9.67 nM in a pronounced linear GA concentration range spanning from 0.1 to 30 μM. The designed electrochemical analysis platform demonstrated satisfactory performance in terms of reproducibility, repeatability, and anti-interference performance. The good quantitative analysis property of GA in food samples could be realized at the above DMPS@CGNP/GCE sensor. This research provides a significant reference for the development of highly sensitive GA electrochemical analysis technology.