Preparation And Bioelectrochemical Performance Of Composite Nanofibers Membrane Based On Electrospinning

Electrospinning technology can be used as a preparation of nanofiber with the diameterof hundreds nanometers, which is simple, low cost and effective. This electrospinningnanofiber membrane with connected porous structure, a novel compositematerial combiningthe advantages of large specific surface area, strong adsorption capacity and high surfacereactivty, is widely applied in optoelectronic devices, sensor technology and tissueengineering.In this study, a novel biosensor and biological fuel cell were prepared based onnanocomposite fiber. The application of electrospun nanocomposite fiber made the sensitivityof biosensor significantly enhanced, and the performance of biofuel improved.Firstly, the Hb-collagen microbelt modified electrode with three-dimensionalconfiguration was fabricated via the electrospinningmethod. Direct electron transfer of the Hbimmobilized into the electrospun collagen microbelts was greatly facilitated. The apparentheterogeneous electron transfer rate constant （ks） was calculated to be273.88±2.22s-1. Theelectrospun Hb–collagen microbelt modified electrode showed an excellent bioelectrocatalyticactivity toward the reduction of H2O2. The amperometric response of the biosensor variedlinearly with the H2O2detection limit of0.37×106mol·L^-1（signal-to-noise ratio of3）. Theapparent Michaelis–Menten constant （Kap^pm） was77.7μmol·L^-1.Secondly, Single-walled carbon nanotubes （SWNTs） and hemoglobin （Hb） wereco-electrospun to generate Hb-SWNTs, a novel compositematerial combining the advantagesof excellent electron transfer property of SWNTs, and electrocatalytic capability of redox Hbproteins. FT-IR spectra confirmed that Hb in the microbelts kept its native conformationalstructure. The direct electrochemistry of Hb-SWNTs composite microbelts was investigatedand its application for electrocatalytic reductions and sensitive detections of three compounds,nitrite, and hydrogen peroxide （H2O2） was also conducted. The Hb-SWNTscompositemicrobelts based amperometric biosensor showed fast responses to the analyteswith excellent detection limits of0.46±0.027μmol·L^-1for H₂O₂, and0.044±0.0082μmol·L^-1for nitrite（S/N=3）, respectively.Finally, A glucose/O2biofuel cell （BFC） based on electrospun collagen-SWNTsnanofibres with the glucose oxidase （GOD） as the anodic biocatalysts and the laccase as the cathodic biocatalysts is reported in this paper. The GOD and laccase immobilized into thecollagen-SWNTs nanofibres exhibited good catalytic activity towards glucose oxidation andoxygen reduction by mediators ferrocene monocarboxylic acid （FMCA） and ABTS,respectively. The maximum power density was ca.14.3μW cm-2for the assembledglucose/O2BFC based on electrospun collagen-SWNTs nanofibres. Moreover, the powerdensity remains more than50%of its initial value after100h of continuous operation.