single rp-hplc method for the estimation of losartan ... - Ijsidonline.info

L. Bhaskar Reddy et al., IJSID 2011, 1 (1), 33-40hydroxypropyl methylcellulose, titanium dioxide. The capsules tested contained lactose, corn starch,magnesium stearate and colloidal silicon dioxide as excipients. Injections of placebo tablet solutionsshowed no interference with the main peak.Range of linearity: Standard curves were constructed daily, for three consecutive days, using sixdifferent concentrations in a range 50 to 100 μg/ml for all actives. This concentration range correspondsto levels of 50-150% w/w of the nominal analytical concentration. The linearity of peak area responsesversus concentrations was demonstrated by linear least square regression analysis. The linearity ofcorrelation coefficient of Losaratin Potassium is 0.999, Enalapril maleate is 0.999 andHydrochlorothiazide is 0.999. Results were tabulated in table-1, overlaid chromatograms wererepresented in figure-4. Linearity graph plotted between area and concentration and represented ingraph-1.LinearitylevelTable-1: Linearity resultsLinearity ResultsLosartan Potassium Hydrochlorothiazide Enalapril MaleateConc.Area Conc. Area Conc. Area(ppm)(ppm)(ppm)1 50 239629 50 199926 50 1271212 60 285466 60 234067 60 1476083 70 334490 70 265294 70 1693714 80 380586 80 304913 80 1896665 90 424743 90 338487 90 2115316 100 481017 100 378888 100 235212Correlationcoefficient0.9995 0.9993 0.9997Figure-4: Overlaid linearity chromatogramsInternational Journal of Science Innovations and Discoveries VOL1, Issue 1, July-August 201137