Parameter D1 method DD1 method MCR method HPLC method At 290.4 nm At 332 nm At 288.5 nm At 328 nm At 312.8 nm Found  % a Recovery of standard added % b Found  % a Recovery of standard added % b Found  % a Recovery of standard added % b Found  % a Recovery of standard added % b Found  % a Recovery of standard added % c Found  % a Recovery of standard added % c Tibezole® tablets 500 mg OZ/tablet B.N.1319003 99.90 ± .032 101.12 ±0.629 100.86 ± 0.954 100.17 ± 0.606 100.62 ± .452 100.87 ± 0.300 99.88 ± .501 98.91 ± 0.600 98.40 ± 1.204 97.72 ± 0.648 100.97 ± 0.504 100.74 ± 0.372 aAverage of four determinations bAverage of four determinations cAverage of three determinations

Table 4: Results obtained by applying the proposed methods for the determination of OZ in Tibezole® tablets and results obtained by applying standard addition technique.