Identification of ɛ-caprolactam, melamine and urea in polyvinylpyrrolidone powders by micellar electrokinetic chromatography

• Published in: Journal of pharmaceutical and biomedical analysis Vol. 91; pp. 12 - 16
• Main Author: Amini, A.
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.03.2014
• Subjects: Caprolactam - chemistry; Chromatography, Micellar Electrokinetic Capillary - methods; Limit of Detection; MEKC; Melamine; Micelles; Polyvinylpyrrolidone; Povidone; Povidone - chemistry; Powders - chemistry; Sodium Dodecyl Sulfate - chemistry; Triazines - chemistry; Urea - chemistry; ɛ-Caprolactam; Povidone; Polyvinylpyrrolidone; ɛ-Caprolactam; MEKC; Melamine
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2013.12.010

•Successful separation of ɛ-caprolactam, melamine and urea deliberately added to povidone products by SDS-MEKC.•The separations were performed in 50mM phosphate buffer (pH 7.0) containing 2% (w/v) sodium dodecyl sulfate (SDS).•The relative migration times (RMT) were found to be less than 0.15% for intra-day precision and less than 1.0% for inter-day precision.•The detection limits were determined to be 11.5μM, 3.5μM and 0.4mM for ɛ-caprolactam, melamine and urea, respectively. A sodium dodecyl sulfate micellar electrokinetic chromatography (SDS-MEKC) method for the simultaneous separation and identification of ɛ-caprolactam, melamine and urea deliberately added to polyvinylpyrrolidone (povidone) products has been developed. All samples to be analyzed contained paracetamol as an internal marker (IM). The optimized separations were performed in 50mM phosphate buffer (pH 7.0) containing 2% (w/v) sodium dodecyl sulfate (SDS) in fused silica capillaries with UV absorption detection at 200nm. The method was validated with respect to repeatability and intermediate precision, selectivity and robustness with satisfactory results. The relative migration times (RMT) were found to be between 0.03% and 0.13% for intra-day precision and between 0.50% and 0.60% for inter-day precision in four days. The detection limits were determined to be 1.3 (11.5μM), 0.4 (3.5μM) and 41μg/ml (0.4mM) for ɛ-caprolactam, melamine and urea, respectively.