An enhanced biosensor for glutamate based on self-assembled carbon nanotubes and dendrimer-encapsulated platinum nanobiocomposites-doped polypyrrole film.
An enhanced amperometric biosensor based on incorporating one kind of unique nanobiocomposite as dopant within an electropolymerized polypyrrole film has been investigated. The nanobiocomposite was synthesized by self-assembling glutamate dehydrogenase (GLDH) and poly(amidoamine) dendrimer-encapsulated platinum nanoparticles (Pt-DENs) onto multiwall carbon nanotubes (CNTs). Zeta-potentials and high-resolution transmission electron microscopy (HRTEM) confirmed the uniform growth of the layer-by-layer nanostructures onto the carboxyl-functionalized CNTs. The size of Pt nanoparticles is approximately 3 nm. The (GLDH/Pt-DENs)n/CNTs/Ppy hybrid film was obtained by electropolymerization of pyrrole onto glassy carbon electrodes and characterized with scanning electron microscopy (SEM), cyclic voltammetry (CV) and other electrochemical measurements. All methods indicated that the (GLDH/Pt-DENs)n/CNTs nanobiocomposites were entrapped within the porous polypyrrole film and resulted in a hybrid film that showed a high electrocatalytic ability toward the oxidation of glutamate at a potential 0.2 V versus Ag/AgCl. The biosensor shows performance characteristics with high sensitivity (51.48 microA mM(-1)), rapid response (within 3 s), low detection limit (about 10 nM), low level of interference and excellent reproducibility and stability.
Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
Longhua
L
Tang
Yihua
Y
Zhu
Xiaoling
X
Yang
Chunzhong
C
Li
D015374:Biosensing Techniques; D050091:Dendrimers / Q000737:chemistry; D004563:Electrochemistry; D005969:Glutamate Dehydrogenase / Q000737:chemistry; D018698:Glutamic Acid / Q000032:analysis*; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry; D010984:Platinum / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry
D050091:Dendrimers; D037742:Nanotubes, Carbon; D011073:Polyamines; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D018698:Glutamic Acid; D010984:Platinum; D005969:Glutamate Dehydrogenase