HPLC     D1     DD1       iso     official method taken found recovery taken found recovery found recovery at 337.5 found recovery at 334 found recovery at 343     50 48.74 97.49 4 4.01 100.27 4.04 101.1 3.99 99.79 3.99 99.76     100 99.62 99.62 8 7.98 99.72 7.91 98.88 8.02 100.22 8.09 101.18     200 200.4 100.2 12 11.94 99.54 12.19 101.59 12.04 100.37 12.20 101.65     300 306.69 102.23 16 16.22 101.36 15.92 99.49 16.07 100.44 16.04 100.23     400 399.63 99.91 20 19.88 99.39 19.79 98.93 19.73 98.65 19.74 98.72     500 496.48 99.3 24 23.85 99.36 24.07 100.27 24.12 100.51 23.98 99.92           28 28.12 100.42 28.07 100.25 28.03 100.09 28.08 100.30 X- 100.29     99.79     100.01   100.07   100.01   100.25 ±SD 1.226     1.53     0.725   1.041   0.647   0.959 %RSD 1.222     1.533     0.725   1.04   0.647   0.957 N       6     7   7   7   7 t       0.246     0.194   0.219   0.473   0.549 F       1.80     2.057   1.878   1.794   1.052

Table 1: determination and statistical analysis of the results obtained for assay of authentic SAM using, HPLC, D1, DD1, isosbestic point methods compared with official method [1].