Graphene oxide-cellulose composite cryogels for extracellular vesicle isolation

Herein, we present an innovative approach for the selective and high-efficiency isolation of extracellular vesicles (EVs) derived from microfluidic chips that replicate the tumor microenvironment. This is achieved through the development of graphene oxide-cellulose-based composite cryogels imprinted with EVs. In the experiments, MCF-7 cells were cultured under flow conditions within microfluidic chips, simulating the dynamic tumor microenvironment. The isolated EVs were comprehensively characterized in terms of biological, morphological, and quantitative attributes using scanning electron microscopy and nanoparticle tracking analysis. Subsequently, the EVs were imprinted onto graphene oxide-cellulose-based composite cryogels, yielding a novel polymeric material designed for highly selective EV isolation. The physicochemical properties of the composite cryogels were thoroughly analyzed using multiple characterization techniques, and their kinetic performance was evaluated under varying parameters (pH, concentration, temperature, ionic strength, flow rate and selectivity). The maximum adsorption capacity was calculated to be 231 particles/g in a pH 5.0 buffer solution at room temperature. Non-composite and non-imprinted composite cryogels were also prepared for comparison experiments. Finally, the efficacy and validation of the platform were confirmed via high-performance liquid chromatography (HPLC) analysis, demonstrating its potential as a powerful tool for EV isolation in cancer research.