Controllable anchoring of gold nanoparticles to polypyrrole nanofibers by hydrogen bonding and their application in nonenzymatic glucose sensors

An enzymeless glucose biosensor based on polypyrrole nanofibers-supporting Au nanoparticles (Au/PPyNFs) was investigated in this study. The Au/PPyNFs heterogeneous composite materials were synthesized in-situ via hydrogen bonding interactions for the assembly of polyethyleneimine (PEI) on the surface of polypyrrole nanofibers (PPyNFs). By changing the molar ratio of PPy to HAuCl4, Au/PPyNFs with different Au loadings were obtained. The morphology and composition of Au/PPyNFs were characterized using SEM, TEM, FTIR, XRD and XPS, respectively. The hybrids exhibited a high electrocatalytic activity toward glucose oxidation, which is prerequisite for the catalysts to be applied in amperometric glucose sensors. By using the nonenzymatic glucose sensor based on Au/PPyNFs, 0.2–13 mM glucose can be detected with a sensitivity of 1.003 μA cm−2 mM−1 and a good linearity (R2=0.9993) between current density and glucose concentration. The proposed glucose sensor provides a promising strategy to construct fast, sensitive, and anti-interfering amperometric sensors for early diagnosis and prevention of diabetes.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Au NPs were in-situ assembled on PPyNFs via hydrogen bonding as interactions. ► Au/PPyNFs showed good catalytic activity toward glucose oxidation. ► Amperometric glucose sensor based on Au/PPyNFs exhibited good performance to 0∼13 mM glucose.