title: Amperometric enzyme electrodes of glucose and lactate based on poly(diallyldimethylammonium)-alginate-metal ion-enzyme biocomposites.
abstract: Sodium alginate (AlgNa) and poly(diallyldimethylammonium chloride) (PDDA) were mixed to obtain an interpenetrating polymer composite via electrostatic interaction and then cast on an Au electrode surface, followed by incorporation of metal ions (e.g. Fe(3+) or Ca(2+), to form AlgFe or AlgCa hydrogel) and glucose oxidase (GOx) (or lactate oxidase (LOx)), to prepare amperometric enzyme electrodes. The interactions of PDDA, Alg, and Fe(3+) are studied by visual inspection as well as microscopic and electrochemical methods. Under optimized conditions, the PDDA-AlgFe-enzyme/Au and PDDA-AlgCa-enzyme/Au electrodes can give good analytical performance (e.g. nM-scale limit of detection of glucose or lactate, and sensitivities > 50 μA cm(-2) mM(-1)) in the first-generation biosensing mode, which are better than the reported analogs using typical polysaccharide biopolymers as enzyme-immobilization matrices. The enzyme electrodes also worked well in the second-generation biosensing mode in the coexistence of p-benzoquione or ferrocene monocarboxylic acid artificial mediator. Biofuel cells (BFCs) with the enzyme electrodes as the bioanodes and glucose (or lactate) as the biofuel were also fabricated with satisfactory results. The proposed protocols for preparation of high performance Alg-based biocomposites may find wide applications in bioanalysis.
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Cong
authors.initials: C
authors.lastname: Qin
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Qingji
authors.initials: Q
authors.lastname: Xie
authors.forename: Lihua
authors.initials: L
authors.lastname: Wang
authors.forename: Xiuhui
authors.initials: X
authors.lastname: He
authors.forename: Yi
authors.initials: Y
authors.lastname: Huang
authors.forename: Yaping
authors.initials: Y
authors.lastname: Zhou
authors.forename: Fangyun
authors.initials: F
authors.lastname: Xie
authors.forename: Dawei
authors.initials: D
authors.lastname: Yang
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001674:Bioelectric Energy Sources; D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D004800:Enzymes, Immobilized / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000378:metabolism; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D019344:Lactic Acid / Q000032:analysis*; D008670:Metals / Q000737:chemistry*; D006899:Mixed Function Oxygenases / Q000378:metabolism; D011095:Polyethylenes / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D006603:Hexuronic Acids; D007477:Ions; D008670:Metals; D011095:Polyethylenes; D000644:Quaternary Ammonium Compounds; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; D019344:Lactic Acid; D020723:Glucuronic Acid; D006899:Mixed Function Oxygenases; D005949:Glucose Oxidase; C021497:lactate 2-monooxygenase; D005947:Glucose