Biofuel Cell-based Self-powered Biosensor

Enzymatic biofuel cell(EBFCs)has attracted much attention because it can convert chemical or biochemical energy into electric energy.EBFC,as green biological energy,can be used as an energy supply for implantable medical and self-powered sensing devices.In recent years,some non-enzymatic materials with enzyme activity have also been extensively studied.This thesis is mainly focused on self powered sensors based on biofuel cells.The main contents are as follows:1.Nitrogen-doped Hollow Carbon Nanospheres for High-Energy-Density Biofuel Cells and Self-powered Sensing of microRNA-21High-energy-density enzymatic biofuel cells(EBFCs)are an urgent need as not only green energy conversion devices but also as energy generators for medical devices.Excellent electrode materials is the key to improve the power output of EBFC.Herein,we fabricated nitrogen-doped hollow carbon nanospheres with large pores(pNHCSs)via a green microwave-assisted hydrothermal method(MWHM).Thus,the pNHCS-based EBFCs exhibited an outstanding maximum power output(Pmax)of approximately 225 ?W cm-2.Then,based on this EBFC,we developed an innovative self-powered biosensor to sense cancer-related circulating miRNA-21.The detection limits were as low as 0.1 fM for miR-21(S/N=3).This material has excellent potential in the development of superior green biobatteries as well as economical and portable self-powered biomedical sensors.2.An enzyme-free Biofuel Cell-based Self-powered sensor for the drug evaluationDrug evaluation is an important part of medical science research and it is of great significance to improve R&D efficiency,shorten cycle and reduce costs.Herein,for the first time,we devised a enzyme-free glucose-O2 fuel cell-based self-powered sensor for drug evaluation.It was composed of gold nanosemicage covered anode for glucose oxidation and phosphatidylserine(PS)-binding peptide modified nitrogen-doped hollow mesoporous carbon spheres/gold nanoparticles covered(PSp/NCS/AuNPs)cathode to catalyze oxygen reduction.In this design,cell culture medium was directly used as the electrolyte.Then a corresponding time-dependent decrease in Pmax of BFC would be caused by the connection between the apoptotic cells with exposed PS and PS-binding peptide due to blocking effect,which served as a signal to evaluate the therapeutic effect in cell level.We proved the Pmax of BFC was strongly dependent on the therapeutic effect of the drug to the cancer cells.Therefore,the proposed BFC-based sensor has a great promise to be applied as an innovative and powerful tool for drug evaluation.