RP-HPLC Estimation of Imipramine Hydrochloride and Diazepam in Tablets

Area of Science:

• Analytical Chemistry
• Pharmaceutical Analysis

Background:

• Imipramine hydrochloride and diazepam are commonly prescribed medications.
• Simultaneous determination of these drugs in pharmaceutical formulations is crucial for quality control.

Purpose of the Study:

• To develop and validate a simple, rapid, and accurate reversed-phase high-performance liquid chromatographic (RP-HPLC) method for the simultaneous determination of imipramine hydrochloride and diazepam.
• To establish a reliable analytical method for routine quantitative analysis of these drugs in combined pharmaceutical formulations.

Main Methods:

• RP-HPLC with isocratic elution using a mobile phase of methanol:water:0.1M sodium acetate (30:50:20 v/v/v).
• Chromatographic separation was performed on a Chromosil C18 column at a flow rate of 1.0 ml/min.
• Detection was carried out at 243 nm.

Main Results:

• The method achieved good linearity for imipramine hydrochloride (r²=0.999) in the range of 25-150 μg/ml and for diazepam (r²=0.9994) in the range of 5-30 μg/ml.
• The limits of detection (LOD) and quantitation (LOQ) were found to be 0.03 and 0.1 μg/ml for imipramine hydrochloride, and 0.02 and 0.07 μg/ml for diazepam, respectively.
• Excellent recovery rates (100.95-101.52% for imipramine hydrochloride, 99.47-100.33% for diazepam), high precision (<2% RSD), and robustness were demonstrated.

Conclusions:

• The developed RP-HPLC method is simple, rapid, and suitable for the simultaneous quantitative determination of imipramine hydrochloride and diazepam in pharmaceutical formulations.
• This method represents the first reported study for the simultaneous analysis of these two drugs in combination and can be applied for routine quality control.