HPLC       %Recovery drug taken (µg\mL)   standard added(µg\mL) %Recovery   drug taken (µg\mL) standard added (µg\mL) D1   DD1       ISO   SAM FLU SAM FLU SAM FLU SAM FLU SAM FLU SAM FLU SAM at 334 SAM at 337.5 FLU 225 FLU at 231.5 SAM at 343 FLU at 237.5 100 100 50 50 99.00 101.92 10 10 4 4 101.25 99.25 100.25 99.75 100.50 99.75 100.50 101.75 100 100 100 100 101.36 100.96 10 10 6 6 98.50 98.17 102.00 100.33 101.83 101.00 99.67 101.50 100 100 150 150 99.53 100.66 10 10 8 8 101.50 100.62 99.25 99.25 98.63 99.00 99.88 98.52 x-       99.96 101.09         100.42 99.35 100.50 99.77 100.32 99.92 100.01 100.50 ± SD       1.238 0.719         1.665 1.230 1.392 0.542 1.612 1.010 0.438 1.952 %RSD       1.238 0.711         1.658 1.238 1.385 0.543 1.606 1.011 0.438 1.942

Table 6: Results of the application of the standard addition technique for the determination of Seritide® Diskus inhaler by the proposed procedures.