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Publications (3)7 Total impact

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    ABSTRACT: Field amplified sample stacking (FASS) was combined with a simple, rapid, sensitive CE-ESI-MS method to achieve the on-line enrichment and simultaneous determination of Clenbuterol (CLE), Salbutamol (SAL), Terbutaline (TER) and Formoterol (FOR). Samples were diluted in deionized water, and electrokinetic injection (10kV×50s) was employed to carry out FASS. With FASS, the four β2-agonists had simultaneously baseline enhancement as much as 319, 332, 297 and 115 fold, respectively. Consequently, satisfactory LODs (S/N=3) of 0.08, 0.1, 0.1 and 0.5ng/mL for CLE, SAL, TER and FOR were obtained. The separation of the four analytes was performed at 22kV in ammonium acetate/ammonia (20mmol/L, pH 9.0), using 7.5mmol/L acetic acid in isopropanol/water 50/50% (v/v) as sheath liquid. In addition, an excellent linear response was obtained with RSD less than 1.3% for migration times and less than 6.7% for peak areas (n=5). The recoveries of spiked urine samples were in the range of 82.7-101% with RSD lower than 9.8%. The proposed method has been applied to analyze human urine samples successfully.
    Talanta 01/2013; 104C:97-102. · 3.50 Impact Factor
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    ABSTRACT: A new method for analyzing diuretics by capillary electrochromatography using poly (1-hexadecene-co-TMPTMA) monolithic column was established. Experimental conditions including the mobile phase, separation voltage, and injection condition were optimized for the analysis. Under optimized experimental conditions, six diuretics were separated within 11.0 min with the limits of detection (LODs) (S/N = 3) in the range of 0.35 - 0.65 microg/mL. The method showed good linearity (R2 > or = 0.990 8) in the range 1.15 and 86.0 microg/mL. The recoveries obtained from the analysis of spiked urine sample were between 81.9% and 105% with the relative standard deviations (RSDs) lower than 4.7%. It can be concluded that this new method possessed good repeatability and stability in analyzing diuretics, and was successfully applied to the analysis of real urine samples from volunteers. Therefore, this method could be applied to scanning diuretics in human urine samples.
    Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 03/2010; 28(3):253-9.
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    ABSTRACT: A new pressure-assisted capillary electrochromatography coupled with electrospray ionization-mass spectrometry method using a silica-based monolithic column as separation media was developed for the analysis of β2-agonists in human urine. Experimental conditions including the mobile phase, separation voltage, assisted pressure, and sheath liquid were optimized for the analysis: mobile phase composed of 82% (v/v) ACN and 18% (v/v) 20mmol/L ammonium acetate (pH 6.0); separation voltage 25kV; assisted pressure 2bar; and the sheath liquid consisting of 7.5mmol/L acetic acid in isopropanol/water 50/50% (v/v) that was delivered at a flow rate of 3.0μL/min. Six β2-agonists were separated within 12.5min with LODs (defined as S/N=3) in the range of 0.25–2.0ng/mL. The absolute LODs of the developed method for analyzing six β2-agonists ranged from 5.75 to 46.0fg. Method repeatability of run-to-run and column-to-column was satisfactory. The recovery obtained from the analysis of spiked urine samples was between 88.2% and 106% with RSDs lower than 6.68%. The method was successfully applied to the analysis of real urine sample from volunteers.
    Talanta 01/2010; 81(4):1655-1661. · 3.50 Impact Factor