Functionalized PProDOT@nitrogen-doped carbon hollow spheres composites for electrochemical sensing of tryptophan

Abstract In this study, the functional groups (-OH,-SH) grafted poly (3,4-proplenedioxy thiophene)@nitrogen-doped carbon hollow spheres (N-HCS) composites were prepared by a chemical oxidative polymerization method for the electrochemical detection of tryptophan. The relationship between the structure and electrochemical performance were systematically studied. The improvement of synergetic effect resulted from strong non covalent bonding effect between the functional groups of N-HCS and polymers, as well as the interaction between functional groups (-OH,-SH) of polymers and small biomolecules enhanced the sensitivity and catalytic properties of the composites. The constructed sensors from composites of functionalized polymers@N-HCS modified glassy carbon electrodes displayed higher electrochemical sensing behavior for detection of tryptophan than unfunctionalized polymer@N-HCS. Furthermore, the composites of functional groups (-OH, –SH) grafted poly (3,4-proplenedioxy thiophene)@N-HCS exhibited a wide range (0.2–90 μM and 0.1–100 μM), low detection limit (4.16 nM and 9.2 nM) and good sensitivity (382.16 μAmM−1cm−2 and 433.12 μAmM−1cm−2), suggesting that the functional groups (-OH,-SH) grafted poly (3,4-proplenedioxythiophene)@N-HCS could be a promising and convenient material for the electrochemical sensing of tryptophan.