Electrochemical characterization of a superoxide biosensor based on the co-immobilization of cytochrome c and XOD on SAM-modified gold electrodes and application to garlic samples.
This paper describes the characterization and optimization of an amperometric cytochrome c (cyt c)-based sensor for the determination of the antioxidant capacity of pure substances and natural samples. The cyt c and the xanthine oxidase (XOD) enzyme were co-immobilized on the electrode using the combination of several long-chain thiols. The self-assembled monolayer (SAM) was optimized in terms of composition and ratio between thiols. The immobilization protocol for both cyt c and XOD and the SAM formation time were evaluated through electrochemical methods, such as cyclic voltammetry (CV), square wave voltammetry (SWV), chronoamperometry (CA) and impedance spectroscopy (IS). Finally, the biosensor was applied to the determination of the antioxidant capacity of pure alliin and two compounds extracted from garlic bulbs.
Cortina-Puig
Montserrat
M
IMAGES EA 4218, Université de Perpignan Via Domitia, 52 avenue Paul Alduy, 66860 Perpignan Cedex, France. mcortina12@gmail.com
Muñoz-Berbel
Xavier
X
Calas-Blanchard
Carole
C
Marty
Jean-Louis
JL
D000975:Antioxidants / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D003545:Cysteine / Q000031:analogs & derivatives / Q000032:analysis; D045304:Cytochromes c; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D004800:Enzymes, Immobilized; D005737:Garlic / Q000737:chemistry*; D006046:Gold; D013481:Superoxides; D014969:Xanthine Oxidase
D000975:Antioxidants; D004800:Enzymes, Immobilized; C019242:aliin; D013481:Superoxides; D006046:Gold; D045304:Cytochromes c; D014969:Xanthine Oxidase; D003545:Cysteine