title: Online preconcentration of recombinant Arg-Gly-Asp-hirudin using dynamic pH junction for analysis in human urine samples by capillary electrophoresis-mass spectrometry.
abstract: A sensitive and effort-saving method was established and validated for the quantitative determination of recombinant Arg-Gly-Asp-hirudin (rRGD-hirudin) in human urine samples. The assay was performed on a uncoated fused silica capillary of 70 cm x 50 microm I.D. and a positive voltage of 30 kV was applied. The sample was injected under pressure of 50 mbar for 300 s and the temperature of capillary was kept 25 degrees C. Sheath liquid consisting of 30% methanol and 70% of 0.1% formic acid aqueous solution flowing at 7 microL/min was supplied to the CE-electrospray interface. Utilizing the dynamic pH junction technique, a lower limit of quantitation of approximately 35 nM was achieved (concentration coefficiency was about 100-fold) without complex sample preprocessing procedure. CE-MS conditions and parameters were also optimized to obtain better performance. The method has been successfully applied in clinical research of rRGD-hirudin.
authors.affiliation: School of Pharmacy, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China.
authors.forename: Shengmin
authors.initials: S
authors.lastname: Su
authors.forename: Yunqiu
authors.initials: Y
authors.lastname: Yu
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D005561:Formates / Q000737:chemistry; D006629:Hirudins / Q000652:urine*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016018:Least-Squares Analysis; D013058:Mass Spectrometry / Q000379:methods*; D000432:Methanol / Q000737:chemistry; D010446:Peptide Fragments / Q000652:urine*; D011994:Recombinant Proteins / Q000652:urine; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D005561:Formates; D006629:Hirudins; D010446:Peptide Fragments; D011994:Recombinant Proteins; C030544:formic acid; C069897:hirudin (53-64), RGD-; D000432:Methanol