• DOI:10.1021/AC060657O
• Corpus ID: 41231668

Sensitive amperometric immunosensing using polypyrrolepropylic acid films for biomolecule immobilization.

@article{Dong2006SensitiveAI,
  title={Sensitive amperometric immunosensing using polypyrrolepropylic acid films for biomolecule immobilization.},
  author={Hua Dong and Chang Ming Li and Wei Chen and Qin Zhou and Zhaohui Zeng and John H. T. Luong},
  journal={Analytical chemistry},
  year={2006},
  volume={78 21},
  pages={
          7424-31
        }
}

• Hua Dong, Chang Ming Li, +3 authors J. Luong
• Published 22 September 2006
• Chemistry, Biology
• Analytical chemistry

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.