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http://dx.doi.org/10.1016/j.jpba.2009.12.012

has been cited by the following article:

• TITLE: UPLCMS Method Development and Validation of Amlodipine, Hydrochlorthiazide and Losartan in Combined Tablet Dosage Form

  AUTHORS: Anandkumar R. Tengli, G. Shivakumar, B. M. Gurupadayya

  KEYWORDS: UPLCMS, Amlodipine, Hydrochlorothiazide, Losartan, Telmisartan, Simultaneous Estimation

  JOURNAL NAME: American Journal of Analytical Chemistry, Vol.6 No.3, February 4, 2015

  ABSTRACT: A simple, rapid, sensitive and specific UPLCMS method was developed and validated following ICH guidelines for simultaneous estimation of tablet dosage form containing amlodipine (AMLO) hydrochlorothiazide (HCT) and losartan (LOSAT) using telmisartan (TELMI) as an internal standard (IS). The separation was achieved using Waters ACQUITY BEH C18 (1.7 μm, 2.1 × 50 mm) column with gradient mode, mobile phase containing acetonitrile (A) & 1% ammonium acetate (B) pH adjusted to 2.8 with trifluoro acetic acid with gradient mode. The flow rate was 0.4 mL·mL﹣1 and the injection volume 2 μl. The retention time for amlodipine, hydrochlorothiazide and losartan was found to be 3.7, 2.5 and 3.9 min, respectively. The developed method was found to be linear over the concentration range of 50 - 300 ng·mL﹣1, 125 - 750 ng·mL﹣1 and 500 - 3000 ng·mL﹣1 for AMLO, HCT and LOSAT respectively. The signal intensities obtained in ion mode for amlodipine, hydrochlorothiazide, losartan and telmisartan (IS) they were found to be much higher positive ion mode (M+)﹣ parent ion at m/z, 409.02, 297.97, 422.91 and 515.03, respectively, in QUATTROZQ full scan mass spectra.