Simultaneous injection effective mixing analysis system for the determination of direct bilirubin in urinary samples

• Main Authors: Ponhong K., Teshima N., Grudpan K., Motomizu S., Sakai T.
• Format: Article
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-81355127204&partnerID=40&md5=a5e4bb9fc463ee7103ae3231278ec20e; http://cmuir.cmu.ac.th/handle/6653943832/6394
• Institution: Chiang Mai University

A novel simultaneous injection effective mixing analysis system (SIEMA) for determination of direct bilirubin in urine sample was developed. Bilirubin reacts with diazotized sulfanilic acid in the presence of n-octyl-β-d- thioglucoside (OTG) as a solubilizing agent to form OTG-azobilirubin. The flow and chemical variables were investigated. A linear calibration graph for direct bilirubin was obtained over the range of 0-1.0 mg L-1 (r2 = 0.994) with the limit of detection (3σ) of 4.7 μg L-1, and the relative standard deviation (RSD) being 1.9% (n = 11, 0.5 mg L-1 of direct bilirubin). The results in healthy adult urine obtained by the proposed approach were found in good agreement with those obtained by the batch-wise diazo method. © 2011 Elsevier B.V. All rights reserved.