Parameters Variables Mean Retention time % RSD Mean peak area %RSD Flow rate 0.8 ml 6.09 0.123 211.4 0.250 1.2 ml 4.03 0.186 210.8 0.383 Wavelength 237 nm 4.79 0.215 216.0 0.096 241 nm 4.8 0.204 215.6 0.301

Table 5: Result of robustness study.