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.
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.
Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, PR China.
Guang-Zhi
GZ
Gu
Hui-Min
HM
Xia
Zhi-Qing
ZQ
Pang
Zhong-Yang
ZY
Liu
Xin-Guo
XG
Jiang
Jun
J
Chen
D002853:Chromatography, Liquid / Q000379:methods*; D004111:Dimenhydrinate / Q000032:analysis; D004355:Drug Stability; D006801:Humans; D016014:Linear Models; D019804:Mesalamine / Q000097:blood* / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D013427:Sulfapyridine / Q000097:blood* / Q000493:pharmacokinetics; D012460:Sulfasalazine / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D053719:Tandem Mass Spectrometry / Q000379:methods*
D012460:Sulfasalazine; D019804:Mesalamine; D004111:Dimenhydrinate; D013427:Sulfapyridine