condition of assay inject 20 u03bcl of reference solution a adjust the sensitivity of the system so that the height of the peak corresponding to the major constituent in the chromatogram obtained is 10 u02dc 25 of the full scale of the recorder inject again 20 u03bcl of test solution a record the chromatogram if there are peaks of impurities in the chromatogram obtained with test solution a measure the sum of the area of each impurities peaks which should not be greater than 1 0 percent of the area of the major constituent peak in reference solution a 1 0 chiral colume chiralcel od rh 150 u00d7 4 6 mm acetonitrile water 30 70 as mobile phase detection wavelength at 256 nm the resolution of two isomer 39 s peaks in the test solutions for system suitability should be meet the specification accurately weight 25 mg of voriconazole reference in 50 ml volumetric flask and dilute with the mobile phase to 50 ml then accurately measure 10 ml of voriconazole reference solution and 1 ml of isomer reference stock solution in 50 ml volumetric flask dilute to 50 ml with the mobile phase each 1 ml of this resulting solution comprises 100 u03bcg of voriconazole and 10 u03bcg of its isomer use as test solution for system suitability isomer stock solution accurately weight 25 mg of voriconazole isomer reference in 50 ml volumetric flask dilute with the mobile phase to 50 ml reference solution b of voriconazole.