Enantioseparation of nuarimol by affinity electrokinetic chromatography-partial filling technique using human serum albumin as chiral selector

• Published in: Journal of separation science 2008-10, Vol.31 (18), p.3265-3271
• Main Authors: Martínez-Gómez, Maria Amparo, Escuder-Gilabert, Laura, Villanueva-Camañas, Rosa M., Sagrado, Salvador, Medina-Hernández, Maria J.
• Format: Article
• Language: English
• Subjects: Affinity electrokinetic chromatography; Analytical chemistry; Animals; Biological and medical sciences; Chemical control; Chemistry; Chiral separation; Chromatographic methods and physical methods associated with chromatography; Chromatography, Affinity - instrumentation; Chromatography, Affinity - methods; Control; Exact sciences and technology; Female; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Human serum albumin; Humans; Molecular Structure; Nuarimol enantiomers; Other chromatographic methods; Partial filling technique; Phytopathology. Animal pests. Plant and forest protection; Pyrimidines - isolation & purification; Reproducibility of Results; Serum Albumin - chemistry; Software; Stereoisomerism
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.200800190

The present paper deals with the enantiomeric separation of nuarimol enantiomers by affinity EKC‐partial filling technique using HSA as chiral selector. Firstly, a study of nuarimol interactions with HSA by CE‐frontal analysis was performed. The binding parameters obtained for the first site of interaction were n1 = 0.84; K1 = 9.7 ± 0.3×103 M–1 and the protein binding percentage of nuarimol at physiological concentration of HSA was 75.2 ± 0.2%. Due to the moderate affinity of nuarimol towards HSA the possibility of using this protein as chiral selector for the separation of nuarimol using the partial filling technique was evaluated. A multivariate optimization approach of the most critical experimental variables in enantioresolution, running pH, HSA concentration and plug length was carried out. Separation of nuarimol enantiomers was obtained under the following selected conditions: electrophoretic buffer composed of 50 mM Tris at pH 7.3; 160 μM HSA solution applied at 50 mbar for 156 s as chiral selector; nuarimol solutions in the range of 2–8×10–4 M injected hydrodynamically at 30 mbar for 2 s and the electrophoretic runs performed at 30°C applying 15 kV voltage. Resolution, accuracy, reproducibility speed and cost of the proposed method make it suitable for quality control of the enantiomeric composition of nuarimol in formulations and for further toxicological studies. The results showed a different affinity between nuarimol enantiomers towards HSA.