Photoelectrochemical immunosensor for label-free detection and quantification of anti-cholera toxin antibody.
We demonstrate herein a newly developed photoelectrochemical immunosensor for the determination of anti-cholera toxin antibody by using a photosensitive biotinylated polypyrrole film. The latter was generated by electro-oxidation of a biotinylated tris(bipyridyl) ruthenium(II) complex bearing pyrrole groups. The photoexcitation of this modified electrode potentiostated at 0.5 V vs SCE, in the presence of an oxidative quencher, pentaaminechloro cobalt(III) chloride (15 mM), led to a cathodic photocurrent. As a result of the affinity interactions, a layer of biotinylated cholera toxin was firmly bound to the functionalized polypyrrole film via avidin bridges. The resulting modified electrodes were tested as immunosensors for the detection of the corresponding antibody from 0 to 200 microg mL(-)(1). The antibody concentration was measured through the decrease in photocurrent intensity resulting from its specific binding onto the polymeric coating, the detection limit being 0.5 microg mL(-)(1).
Haddour
Naoufel
N
Laboratoire d'Electrochimie Organique et de Photochimie Rédox (CNRS UMR 5630), Institut de Chimie Moléculaire de Grenoble FR CNRS 2607, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 9, France.
Chauvin
Jérôme
J
Gondran
Chantal
C
Cosnier
Serge
S
D000906:Antibodies / Q000737:chemistry* / Q000276:immunology*; D000915:Antibody Affinity; D001360:Avidin / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods; D002772:Cholera Toxin / Q000276:immunology*; D004563:Electrochemistry; D008567:Membranes, Artificial; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry; D010777:Photochemistry; D011108:Polymers; D012428:Ruthenium / Q000737:chemistry; D013499:Surface Properties
D000906:Antibodies; D008567:Membranes, Artificial; D009942:Organometallic Compounds; D011108:Polymers; D001360:Avidin; D012428:Ruthenium; D002772:Cholera Toxin