LAUSR

A highly sensitive and specific glucose (Glu) amperometric biosensor was successfully developed by the covalent immobilization of glucose oxidase (GOx) onto the electro-synthesized ionic liquid (ILs) modified poly(3,4-ethylenedioxylthiophene) derivative poly(hydroxymethylated-3,4ethylenedioxylthiophene) (PEDOTM) nanocomposite based on multi-walled carbon nanotubes functionalized with carboxyl group (MWCNTs-COOH). A highly-stable and conducting PEDOTM was one-step electro-synthesized in water/ILs mixed system containing BmimPF6 and MWCNTsCOOH, then GOx was covalently immobilized onto the biocompatible ILs modified PEDOTMMWCNTs-COOH with high affinity, which was employed for amperometric biosensing of Glu in human urine, human and animal serum samples. IL/PEDOTM-MWCNTs-COOH displayed good electrochemical activity, excellent electrochemical stability and high conductivity. The fabricated GOx biosensor showed pronounced amperometric current toward Glu response in a wide linear range of 6.0×10 ~2×10 M with a high sensitivity of 89.5 μA M cm, rapid response time within 10 s, low limit of detection of 0.015 μM, remarkable biocompatibility and bioaffinity, high sensing stability, excellent selectivity and practicality. Satisfactory results reveal that the ILs-PEDOTM-MWCNTsCOOH will provide a promising biosensing platform for the covalent immobilization of biomacromolecules and disease diagnostics via the detection of Glu in human and animal serum samples.