Aim:

Ketobemidone is an opioid drug that have been using against pain in various circumstances. The current research was aimed to develop and validate a HPLC-PDA method to estimate the ketobemidone in rat plasma.

Materials and Methods:

The ketobemidone in the biological matrices (rat plasma) was separated using solvent extraction method using methanol as extracting solvent. An isocratic mobile phase consisting of methanol-water-phosphate buffer at 40:60:0.01 % v/v/v and Kromasil C₁₈ column were used for separation in Liquid Chromatography (LC).

Results:

The selected linearity range i.e., 0.10-25μg/mL was acceptable with r² value 0.9998 as least square method. The determined Lower Limit of Quantification (LLOQ) is 0.10 μg/mL. The intermediate precision studies were performed within and between days; and the data obtained are within a significant range, i.e., %RSD <9.2 and the accuracy was within 10.0% of the relative error.

Conclusion:

The developed method to detect the ketobemidone was successfully validated and it was successfully applied on rat pharmacokinetic study.