title: Myelin basic protein immunosensor for multiple sclerosis detection based upon label-free electrochemical impedance spectroscopy.
abstract: A novel highly sensitive impedimetric Myelin Basic Protein (MBP) immunosensor for the determination of a Multiple Sclerosis (MS) autoantibody, Anti-Myelin Basic Protein (Anti-MBP) was developed by immobilization of MBP on Gelatin and Gelatin-Titanium Dioxide (TiO₂) modified platinium electrode. Cyclic voltammetric (CV) and Electrochemical Impedance Spectroscopic (EIS) methods were employed in determination of the electrode responses and applicability. Gelatin-MBP and gelatin-TiO₂-MBP electrodes were prepared by chemical immobilization of the substrates onto the platinium electrodes. The formal potentials of MBP confined on gelatin-MBP and gelatin-TiO₂-MBP surfaces are estimated to be 195 and 205 mV, respectively. Thus, a little more reversible electron transfer reaction occurs on the gelatin-TiO₂-MBP immunosensor surface. The peak separations of MBP (150 mV and 110 mV s(-1) at 100 mV s(-1)) and the asymmetric anodic and cathodic peak currents indicate that the electron transfer between Anti-MBP and gelatin-MBP/gelatin-TiO₂-MBP immunosensor is quasireversible. Control samples containing a nonspecific human immunoglobulin G (hIgG) antibody were also studied, and calibration curves were obtained by subtraction of the responses for specific and nonspecific antibody-based sensors. Gelatin-MBP and gelatin-TiO₂-MBP immunosensors have detection limit of 0.1528 ng ml(-1) and 0.1495 ng ml(-1) respectively. This immunosensor exhibits high sensitivity and low response times (58 s for gelatin-MBP and 46 s for gelatin-TiO₂-MBP immunosensor). The developed label-free impedimetric immunosensors also provide a simple and sensitive detection method for the specific determination of Anti-MBP in human cerebrospinal fluid (CSF) and serum samples.
authors.affiliation: Ankara University, Department of Chemistry, Science Faculty, Tandoğan, Ankara 06100, Turkey.
authors.forename: Burak
authors.initials: B
authors.lastname: Derkus
authors.forename: Emel
authors.initials: E
authors.lastname: Emregul
authors.forename: Canan
authors.initials: C
authors.lastname: Yucesan
authors.forename: Kaan
authors.initials: K
authors.lastname: Cebesoy Emregul
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods; D058266:Dielectric Spectroscopy / Q000379:methods*; D004566:Electrodes; D005780:Gelatin / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods; D057230:Limit of Detection; D009103:Multiple Sclerosis / Q000097:blood* / Q000134:cerebrospinal fluid*; D004676:Myelin Basic Protein / Q000097:blood* / Q000134:cerebrospinal fluid*; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D015203:Reproducibility of Results; D014025:Titanium / Q000737:chemistry
chemical_list: D055910:Antibodies, Immobilized; D004676:Myelin Basic Protein; C009495:titanium dioxide; D005780:Gelatin; D014025:Titanium