title: Voltammetric determination of sinomenine in biological fluid using a glassy carbon electrode modified by a composite film of polycysteic acid and carbon nanotubes.
abstract: Polycysteic acid based electrochemical oxidation of L-cysteine (CySH) and carbon nanotubes (CNTs) formed a composite thin film material at a glassy carbon electrode (GCE) that was used a novel modifier for electroanalytical determination of sinomenine which is used for rheumatoid arthritis treatment. The determination of sinomenine at the composite modified electrode was studied by differential pulse voltammetry (DPV). The peak current obtained at + 0.632 V (vs SCE) from DPV was linearly dependent on the sinomenine concentration in the range of 1.0 x 10(-7) to 6.0 x 10(-5) M in a B-R buffer solution (0.04 M, pH 1.81) with a correlation coefficient of 0.998. The detection limit (S/N = 3) was 5.0 x 10(-8) M. The electrochemical reaction mechanism of sinomenine was also discussed. This new method was then applied to the high-throughput determination of sinomenine in human serum samples with satisfactory results. This polycysteic acid/CNTs composite film may be considered to be a promising, low-cost, durable, and biocompatible material for the modification of sensors in applications to pharmaceutical and biomedical analysis.
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, China.
authors.forename: Chengyin
authors.initials: C
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Guan
authors.forename: Qishu
authors.initials: Q
authors.lastname: Qu
authors.forename: Gongjun
authors.initials: G
authors.lastname: Yang
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Hu
mesh_terms: D002244:Carbon / Q000737:chemistry*; D003544:Cysteic Acid / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D015394:Molecular Structure; D009019:Morphinans / Q000097:blood*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D008567:Membranes, Artificial; D009019:Morphinans; D037742:Nanotubes, Carbon; D011108:Polymers; C009271:sinomenine; D002244:Carbon; D003544:Cysteic Acid