title: Electrochemical immunosensor based on colloidal carbon sphere array.
abstract: A novel type of colloidal carbon sphere array (CSA) was developed for the fabrication of disposable electrochemical immunosensor. The CSA was successfully prepared on indium tin oxide (ITO) substrate in a simple manner and the scanning electron micrograph confirmed that a single-layered arrangement of the carbon spheres with its (111) plane paralleled the substrate's surface. The CSA modified electrode has a higher surface area and exhibits a more sensitive electrochemical response than a normal carbon-based electrode with the same geometric area. An Immunoglobin A (IgA) immunosensor was constructed by the covalent bonding of IgA antibody molecules with the CSA aided by large numbers of carboxyl groups on the surface of carbon spheres. The immunosensor exhibited a wide linear response to IgA ranging from 0.1 to 200 ng mL(-1) by electrochemical impedance spectroscopy (EIS) technique. The detection of IgA levels in three sera obtained from hospital samples showed acceptable accuracy.
authors.affiliation: Key Lab of Analytical Chemistry for Life Science (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, PR China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Chen
authors.forename: Kui
authors.initials: K
authors.lastname: Zhang
authors.forename: Jinjun
authors.initials: J
authors.lastname: Zhou
authors.forename: Jie
authors.initials: J
authors.lastname: Xuan
authors.forename: Wei
authors.initials: W
authors.lastname: Yan
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Jiang
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Zhu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002244:Carbon / Q000737:chemistry*; D003102:Colloids / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D007070:Immunoglobulin A / Q000032:analysis*; D008863:Microspheres; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003102:Colloids; D007070:Immunoglobulin A; D002244:Carbon