Preparation of porous graphene using cuprous oxide microspheres as sacrificial templates for enriching proteins and peptides

Porous graphene was prepared by dissolving the sacrificial templates of cuprous oxide microsphere (Cu2OMS) in the composite of graphene and Cu2OMSs with diluted nitric acid. The composite was synthesized by the chemical reduction of a mixture containing graphene oxide, copper(II) sulfate in the presence of glucose and sodium hydroxide. The morphologies and structures of the prepared materials were investigated by scanning electron microscopy, energy dispersive spectroscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. The average size of the pores in the prepared porous graphene was measured to be ∼1.37 μm. The prepared graphene with a three-dimensional architecture was successfully employed in the enrichment and determination of low-abundance proteins and peptides based on its large surface area, unique structure, and high hydrophobicity, indicating great promise for a wide range of applications.