Preparation Of Three-dimensional Amylopectin-reduced Graphene Oxide Composite And Its Adsorption Behaviors Towards Proteins

Attributed to the unique intrinsic physical-chemistry properties of graphene derivatives and three-dimensional(3D)porous structure,the 3D graphene materials exhibit larger specific surface area,stronger mechanical property,improved mass-/electron transferring rate when compared with 2D graphene nanosheets.At the same time,the aggregation of graphene nanosheets could be efficiently avoided in the preparation of macro-sized materials by self-assembly process,therefore,3D graphene materials have attracted extensive attentions.Based on the hydrogen-bond interaction between amylopectin and graphene oxide,a 3D graphene oxide composite is prepared in the present work via a simple and cost-effective one-pot approach in the presence of hydrazine hydrate.The as-prepared composite is shortly termed as AP-rGO and characterized by Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),surface charge analysis,thermogravimetric analysis(TGA)and nitrogen sorption-desorption.Theperformance of the obtained AP-rGO composite in the adsorption of proteins is investigated and the results indicate that it exhibits excellent adsorption selectivity towards hemoglobin(Hb)in the presence of other protein species.At pH 7,the adsorption efficiency towards 1.0 mL of 70 mg L-1 Hb is 92.7%by using 1.0 mg of AP-rGO composite as adsorbent,while nearly no adsorption of serum albumin takes place under such circumstance.The coordination and hydrophobic interactions are demonstrated to be the main driving forces for Hb adsorption,and the maximum adsorption capacity is deduced to be 1010 mg g-1.The practical application of the AP-rGO composite is demonstrated by the removal of Hb from complex biological sample matrices,i.e.,human whole blood.The removal efficiency is well confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)assay.