Capillary electrophoresis coupled with chloroform‐acetonitrile extraction for rapid and highly selective determination of cysteine and homocysteine levels in human blood plasma and urine. Issue 20 (1st August 2017)

• Record Type: Journal Article
• Authors: Ivanov, Alexander Vladimirovich; Bulgakova, Polina Olegovna; Virus, Edward Danielevich; Kruglova, Maria Petrovna; Alexandrin, Valery Vasil'evich; Gadieva, Viktoriya Aleksandrovna; Luzyanin, Boris Petrovich; Kushlinskii, Nikolai Evgen'evich; Fedoseev, Anatolij Nikolaevich; Kubatiev, Aslan Amirkhanovich
• Other Names: Flanagan Lisa A. guestEditor.; Labeed Fatima H. guestEditor.; Lapizco‐Encinas Blanca H. guestEditor.
• Is Part Of: Electrophoresis. Volume 38:Issue 20(2017)
• Page Start: 2646
• Page End: 2653
• Publication Date: 2017-08-01
• Subjects: 1, 1′‐thiocarbonyldiimidazole -- Capillary electrophoresis -- Cysteine -- Homocysteine -- Liquid–liquid extraction; Electrophoresis -- Periodicals; Electrophoresis -- Periodicals; 541.372
• DOI: 10.1002/elps.201700133
• Languages: English
• ISSNs: 0173-0835

Abstract

Abstract: A rapid and selective method has been developed for highly sensitive determination of total cysteine and homocysteine levels in human blood plasma and urine by capillary electrophoresis (CE) coupled with liquid–liquid extraction. Analytes were first derivatized with 1, 1′‐thiocarbonyldiimidazole and then samples were purified by chloroform–ACN extraction. Electrophoretic separation was performed using 0.1 M phosphate with 30 mM triethanolamine, pH 2, containing 25 μM CTAB, 2.5 μM SDS, and 2.5% polyethylene glycol 600. Samples were injected into the capillary (with total length 32 cm and 50 μm id) at 2250 mbar*s and subsequent injection was performed for 30 s with 0.5 M KОН. The total analysis time was less than 9 min, accuracy was 98%, and precision was <2.6%. The LOD was 0.2 μM for homocysteine and 0.5 μM for cysteine. The use of liquid–liquid extraction allowed the precision and sensitivity of the CE method to be significantly increased. The validated method was applied to determine total cysteine and homocysteine content in human blood plasma and urine samples obtained from healthy volunteers and patients with kidney disorders.