TY - JOUR T1 - Determination of sulphasalazine and its main metabolite sulphapyridine and 5-aminosalicylic acid in human plasma by liquid chromatography/tandem mass spectrometry and its application to a pharmacokinetic study. AU - Gu,Guang-Zhi, AU - Xia,Hui-Min, AU - Pang,Zhi-Qing, AU - Liu,Zhong-Yang, AU - Jiang,Xin-Guo, AU - Chen,Jun, Y1 - 2011/01/04/ PY - 2010/09/25/received PY - 2010/12/16/revised PY - 2010/12/29/accepted PY - 2011/1/22/entrez PY - 2011/1/22/pubmed PY - 2011/6/4/medline SP - 449 EP - 56 JF - Journal of chromatography. B, Analytical technologies in the biomedical and life sciences JO - J Chromatogr B Analyt Technol Biomed Life Sci VL - 879 IS - 5-6 N2 - A simple and sensitive liquid chromatography/positive-ion electrospray ionization mass spectrometry (LC-ESI-MS/MS) method has been developed for the simultaneous determination of sulphasalazine (SASP) and its main metabolite sulphapyridine (SP) and 5-aminosalicylic acid (5-ASA) with 100 μL of human plasma using dimenhydrinate as the internal standard (I.S.). The API-3000 LC-MS/MS was operated under the multiple reaction-monitoring mode (MRM) using the electrospray ionization technique. Protein precipitation process was used to extract SASP, SP, 5-ASA and I.S. from human plasma. The total run time was 9.0 min and the elution of SASP, SP and 5-ASA was at 4.8 min, 2.5 min and 2.0 min, respectively. The separation was achieved with a mobile phase consisting of 0.2% formic acid, 2 mM ammonium acetate in water (mobile phase A) and 0.2% formic acid, 2 mM ammonium acetate in methanol (mobile phase B) by using gradient elution on a XBP Phenyl column (100 mm × 2.1 mm, 5 μm). The developed method was validated in human plasma with a lower limit of quantitation of 10 ng/mL for SASP, SP and 5-ASA, respectively. A linear response function was established for the range of concentrations 10-10,000 ng/mL (r>0.99) for SASP and 10-1000 ng/mL (r>0.99) for SP and 5-ASA. The intra and inter-day precision values for SASP, SP and 5-ASA met the acceptance as per FDA guidelines. SASP, SP and 5-ASA were stable during stability studies, i.e., long term, auto-sampler and freeze/thaw cycles. The method was successfully applied for the evaluation of pharmacokinetics of SASP, SP and 5-ASA after single oral doses of 250 mg SASP to 10 healthy volunteers. SN - 1873-376X UR - https://www.unboundmedicine.com/medline/citation/21251889/Determination_of_sulphasalazine_and_its_main_metabolite_sulphapyridine_and_5_aminosalicylic_acid_in_human_plasma_by_liquid_chromatography/tandem_mass_spectrometry_and_its_application_to_a_pharmacokinetic_study_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1570-0232(10)00790-7 DB - PRIME DP - Unbound Medicine ER -