HPTLC Method Development and Validation for the Simultaneous Estimation of Nortriptyline HCl and Pregabalin in their Combined Dosage Form

Nortriptyline HCl and pregabalin Tablet is used to treat neuropathic pain as well as mental or mood issues such as sadness, mood, feelings, anxiety and tensions. Very few analytical methods are available for the simultaneous estimation of nortriptyline HCl and pregabalin and no reports has been found for HPTLC method. In the current study, a reliable HPTLC method for the simultaneous measurement of nortriptyline HCl and pregabalin in pure forms and pharmaceutical formulations has been developed with ninhydrine post derivatization of pregabalin. The HPTLC method development was carried using silica gel G60 F254 as stationary phase and acetonitrile: methanol: triethylamine: water: formic acid (7:3:0.3:0.8:0.02 v/v/v/v/v) was used as mobile phase with saturation time of 20 min. The system was found to give a compact band for nortriptyline HCl (Rf = 0.523 +/- 0.008) pregabalin (Rf = 0.279 +/- 0.005). The developed method was found to be validated as per ICH Q2 (R1) guideline. The peak of nortriptyline HCl and pregabalin showed good linearity over the concentration range of 50-300 ng/band and 350-2250 ng/band, respectively, with a correlation coefficient of >0.995. The % recoveries of both drugs were found to be in the range of 98.84-101.87%. Statistical analysis proved that the method is selective, precise, robust and accurate for the estimation of nortriptyline HCl and pregabalin.