Microwave-prepared mesoporous graphene as adsorbent and matrix of surface-assisted laser desorption/ionization mass spectrometry for the enrichment and rapid detection of polyphenols in biological samples.

In this work, a three-dimensional mesoporous graphene (3D-MG) prepared by microwave-assisted method was used as both the adsorbent and the matrix of SALDI-TOF MS for polyphenols analysis in biological samples. The outstanding microstructure of 3D-MG made it sensitive in small molecule analysis with low background interference and able to enrich trace polyphenols from complex samples. 3D-MG performed much better in the detection of small molecules than graphene prepared by ordinary method, and could further improve sensitivity and reduce detection limit by enrichment. Due to its unique hierarchical mesoporous structure, the interference of biological macromolecules in SALDI analysis could be eliminated after treatment by 3D-MG. Finally, 3D-MG was successfully applied to the screening of polyphenols in biological samples with simple process and high throughput. Moreover, this strategy had also promoted the development of new matrix in SALDI-TOF MS analysis, in which the matrix properties, adsorption capabilities and size effects of graphene-based materials were combined for the first time.