title: Combination of capillary micellar liquid chromatography with on-chip microfluidic chemiluminescence detection for direct analysis of buspirone in human plasma.
abstract: Microfluidic based chemiluminescence (CL) detector having novel channel design for enhanced mixing has been developed and investigated in terms of its applicability with micellar mode of liquid chromatography (MLC). The newly developed detector was found to be highly sensitive and an alternative detection technique to combine with capillary MLC. This combination was successfully employed for direct detection of a model analyte using Ru(III)-peroxydisulphate CL system. The selected analyte, buspirone hydrochloride (BUS), was detected selectively at therapeutic concentration levels in human plasma without any sample pretreatment. By incorporating eight flow split units within the spiral channel of microfluidic chip, an enhancement of 140% in CL emission was observed. We also evaluated the effect of non- ionic surfactant, Brij-35, which used as mobile phase modifier in MLC, on CL emission. The CL signal was improved by 52% compared to aqueous-organic mobile phase combinations. Various parameters influencing the micellar chromatographic performance and the CL emission were optimized. This allowed highly sensitive analysis of BUS with limit of detection (LOD) of 0.27 ng mL(-1) (3σ/s) and limit of quantification (LOQ) of 0.89 ng mL(-1) (10σ/s). The analyte recovery from human plasma at three different concentration level ranges from 88% to 96% (RSD 1.9-5.3%). The direct analysis of BUS in human plasma was achieved within 6 min. Therefore, combining microfluidic CL detection with micellar mode of separation is an efficient, cost-effective and highly sensitive technique that can utilize MLC in its full capacity for various bioanalytical procedures.
authors.affiliation: Department of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, Al-Khod, Muscat 123, Oman. Electronic address: haiderl@squ.edu.om.
authors.forename: Haider A J
authors.initials: HA
authors.lastname: Al Lawati
authors.affiliation: Department of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, Al-Khod, Muscat 123, Oman.
authors.forename: Afsal Mohammed
authors.initials: AM
authors.lastname: Kadavilpparampu
authors.affiliation: Department of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, Al-Khod, Muscat 123, Oman.
authors.forename: FakhrEldin O
authors.initials: FO
authors.lastname: Suliman
mesh_terms: D014151:Anti-Anxiety Agents / Q000097:blood*; D002065:Buspirone / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D055772:Green Chemistry Technology; D006801:Humans; D049449:Luminescence; D008823:Micelles; D044085:Microfluidics; D009942:Organometallic Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D012428:Ruthenium / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry
chemical_list: D014151:Anti-Anxiety Agents; D008823:Micelles; D009942:Organometallic Compounds; D013431:Sulfates; C415768:tris(2,2'-bipyridyl)ruthenium(II); D012428:Ruthenium; D002065:Buspirone
keywords: Buspirone; Capillary liquid chromatography; Chemiluminescence; Micellar liquid chromatography; Microfluidic