Plasma d-penicillamine redox state evaluation by capillary electrophoresis with laser-induced fluorescence

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 803; no. 2; pp. 299 - 304
• Main Authors: Zinellu, Angelo, Carru, Ciriaco, Sotgia, Salvatore, Deiana, Luca
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25.04.2004; Elsevier Science
• Subjects: Analysis; Analytical, structural and metabolic biochemistry; Biological and medical sciences; d-Penicillamine; Fluorescence; Fundamental and applied biological sciences. Psychology; General pharmacology; Hepatolenticular Degeneration - blood; Hepatolenticular Degeneration - drug therapy; Humans; Lasers; Medical sciences; Oxidation-Reduction; Penicillamine - blood; Penicillamine - therapeutic use; Pharmacology. Drug treatments; Reproducibility of Results; Sensitivity and Specificity; Thiols; SSA; d-Penicillamine; TBP; Thiols; d-Pen; 5-IAF; CE-LIF; Human; Drug; Redox state; Biological fluid; Cysteine; Wilson disease; Capillary electrophoresis; Laser induced fluorescence; Penicillamine; Cystinuria; Silica; Blood plasma; Sulfur containing aminoacid; Rheumatoid arthritis; Chelating agent; Glutathione
• DOI: 10.1016/j.jchromb.2004.01.002
• ISSN: 1570-0232

d-Penicillamine ( d-Pen) is a thiol drug used in the treatment of Wilson’s disease, rheumatoid arthritis, metal intoxication and cystinuria. We have recently described a new capillary electrophoresis (CE) method to measure physiological thiols, in which separation of total plasma homocysteine, cysteine, cysteinylglycine, glutathione is achieved using the organic base N-methyl- d-glucamine in the run buffer. In this paper, we present an improvement of our method that allows a baseline separation of total plasma d-Pen from the physiological thiols. Moreover, reduced, free and protein-bound forms of drug are measured by varying the order of disulfide reduction with tributylphosphine and proteins precipitation with 5-sulphosalicylic acid (SSA). After derivatization with 5-iodoacetamidofluorescein (5-IAF), samples are separated and measured by capillary electrophoresis with laser-induced fluorescence in an uncoated fused-silica capillary ( 57 cm×75 μm i.d.) using a phosphate/borate run buffer pH 11.4. In these conditions, the migration time of d-Pen is about 7 min and the time required for each analysis is roughly 10 min. The proposed method has been utilized to measure the various forms of the drug in a d-Pen administered Wilson’s disease patient.