An improved biosensor for acetaldehyde determination using a bienzymatic strategy at poly(neutral red) modified carbon film electrodes.
Improved biosensors for acetaldehyde determination have been developed using a bienzymatic strategy, based on a mediator-modified carbon film electrode and co-immobilisation of NADH oxidase and aldehyde dehydrogenase. Modification of the carbon film electrode with poly(neutral red) mediator resulted in a sensitive, low-cost and reliable NADH detector. Immobilisation of the enzymes was performed using encapsulation in a sol-gel matrix or cross-linking with glutaraldehyde. The bienzymatic biosensors were characterized by studying the influence of pH, applied potential and co-factors. The sol-gel and glutaraldehyde biosensors showed a linear response up to 60 microM and 100 microM, respectively, with detection limits of 2.6 microM and 3.3 microM and sensitivities were 1.7 microA mM(-1) and 5.6 microA mM(-1). The optimised biosensors showed good stability and good selectivity and have been tested for application for the determination of acetaldehyde in natural samples such as wine.
Ghica
Mariana Emilia
ME
Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal.
Pauliukaite
Rasa
R
Marchand
Nicolas
N
Devic
Eric
E
Brett
Christopher M A
CM
D000079:Acetaldehyde / Q000032:analysis*; D000445:Aldehyde Oxidoreductases / Q000737:chemistry*; D015374:Biosensing Techniques; D002244:Carbon; D004396:Coloring Agents; D003432:Cross-Linking Reagents / Q000737:chemistry; D004566:Electrodes; D004800:Enzymes, Immobilized; D005782:Gels; D005976:Glutaral / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009097:Multienzyme Complexes / Q000737:chemistry*; D009243:NAD / Q000032:analysis; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry*; D009499:Neutral Red; D010084:Oxidation-Reduction; D011108:Polymers; D012680:Sensitivity and Specificity; D014920:Wine / Q000032:analysis
D004396:Coloring Agents; D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D005782:Gels; D009097:Multienzyme Complexes; D011108:Polymers; D009243:NAD; D009499:Neutral Red; D002244:Carbon; D000445:Aldehyde Oxidoreductases; C018699:aldehyde dehydrogenase (NAD(P)+); C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D000079:Acetaldehyde; D005976:Glutaral