title: Sensitive detection of an anthrax biomarker using a glassy carbon electrode with a consecutively immobilized layer of polyaniline/carbon nanotube/peptide.
abstract: Sensitivity of Anthrax protective antigen (PA) detection has been improved by directly immobilizing a PA-specific peptide onto a multi-wall carbon nanotube (MWCNT). The MWCNT was covalently immobilized onto a polyaniline (PANI) electrode, which was prepared via electropolymerization of the aniline monomer onto a glassy carbon electrode (GCE). Then, the PA-specific peptide was covalently immobilized to the MWCNT layer for measurement. When comparing this technique to that of PA immobilization on an insulting self assembled organic layer, the advantages of the MWCNT are clear. The MWCNT sensor resulted in enhanced electron transfer across the sensing layer. The resulting limit of detection (LOD) was 0.4 pM, a 13-fold improvement over that of our previous self-assembled organic layer was used for immobilization of the same peptide. Neither positive nor negative interferences were observed when a sample containing both 100 pM PA and bovine serum albumin (BSA) was measured, indicating good selectivity of the proposed sensor.
authors.affiliation: Department of Chemistry and Research Institute for Convergence of Basic Sciences, Hanyang University, Seongdong-Gu, Haengdang-Dong, Seoul 133-791, Republic of Korea.
authors.forename: Tran Ngoc
authors.initials: TN
authors.lastname: Huan
authors.forename: Thothadri
authors.initials: T
authors.lastname: Ganesh
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Han
authors.forename: Moon-Young
authors.initials: MY
authors.lastname: Yoon
authors.forename: Hoeil
authors.initials: H
authors.lastname: Chung
mesh_terms: D000814:Aniline Compounds; D000818:Animals; D000881:Anthrax / Q000175:diagnosis*; D000942:Antigens, Bacterial / Q000032:analysis*; D001427:Bacterial Toxins / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D002417:Cattle; D055664:Electrochemical Techniques; D004566:Electrodes; D055767:Immobilized Proteins; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon; D012680:Sensitivity and Specificity
chemical_list: D000814:Aniline Compounds; D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D015415:Biomarkers; D055767:Immobilized Proteins; D037742:Nanotubes, Carbon; C030325:anthrax toxin; C416807:polyaniline