A plasma-polymerized film for capacitance immunosensing.
A capacitance immunosensor based on a plasma-polymerized ethylenediamine film (PPEF) has been developed. The resulting PPEF is studied with scanning electrode micrograph (SEM), IR reflection spectrum and cyclic voltammetry. SEM and IR reflection spectrum showed that the plasma-polymerized film (PPF) formed on the gold electrode surface is quite homogeneous, flat, nonporous and contains plenty of free-reacted -NH2. Moreover, cyclic voltammetry showed that the hexacyanoferrate redox reactions were blocked well by the formed PPF, that is to say, the formed PPF has excellent insulating characteristics. To investigate its applicability for capacitive immunosensing, goat-anti-human IgG antibody (IgGAb) was coupled to the PPF-coated gold electrode surface via glutaraldehyde (GA) to form an immunoglobulin G (IgG) probe. Alternating current (ac) impedance and capacitance measurement were used in the immunoassay. The experiment results show that the PPEF is applicable to form insulating layer of capacitive immunosensors.
Li
Jishan
J
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
Wang
Hua
H
Deng
Ting
T
Wu
Zhaoyang
Z
Shen
Guoli
G
Yu
Ruqin
R
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D025802:Electric Capacitance; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005029:Ethylenediamines / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D007074:Immunoglobulin G / Q000032:analysis*; D008567:Membranes, Artificial; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D020099:Coated Materials, Biocompatible; D005029:Ethylenediamines; D007074:Immunoglobulin G; D008567:Membranes, Artificial; C031234:ethylenediamine