1. Sensitive amperometric immunosensing using polypyrrolepropylic acid films for biomolecule immobilization.
- Author
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Dong H, Li CM, Chen W, Zhou Q, Zeng ZX, and Luong JH
- Subjects
- Sensitivity and Specificity, Biosensing Techniques, Electrochemistry methods, Propionates chemistry, Pyrroles chemistry
- Abstract
An electrochemical immunosensor was constructed using an electropolymerized pyrrolepropylic acid (PPA) film with high porosity and hydrophilicity. A high density of carboxyl groups of PPA was used to covalently attach protein probes, leading to significantly improved detection sensitivity compared with conventional entrapment methods. As a model, anti-mouse IgG was covalently immobilized or entrapped in the PPA film and used in a sandwich-type alkaline phosphatase-catalyzing amperometric immunoassay with p-aminophenyl phosphate as the substrate. With covalent binding, the detection limit for IgG in PBS buffer, pH 7.4, was 100 pg/mL with a dynamic range of 5 orders of magnitude. The covalent bonding mode in the carbonate-bicarbonate buffer, pH 9.6, further brought down the detection limit to 20 pg/mL with remarkable selectivity.
- Published
- 2006
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