A stability-indicating RP-TLC/Densitometry method for analysis of Raloxifene hydrochloride both in bulk material and in tablets was developed and validated. Densitometric analysis of Raloxifene hydrochloride was carried out at 311？nm on TLC aluminium plates precoated with silica gel 60RP-18 S as the stationary phase and methanol？:？water？:？ammonia (95？:？05？:？0.1 ) as mobile phase. Raloxifene hydrochloride was well resolved at 0.55 ± 0.02. The linear regression analysis data for the calibration plots showed good linear relationship with with respect to peak area in the concentration range 100–600？ng per band. The mean value ± SD of slope and intercept was found to be and with respect to peak area. The limits of detection and quantification were 9.27？ng and 27.10？ng, respectively. Raloxifene hydrochloride was subjected to acid and alkali hydrolysis, oxidation, dry heat, and photodegradation. The drug underwent degradation under basic and oxidation conditions. This indicates that the drug is susceptible to alkali hydrolysis and oxidation. The proposed developed RP-TLC/Densitometry method can be applied for identification and quantitative determination of Raloxifene hydrochloride in bulk material and tablets. 1. Introduction Raloxifene hydrochloride (RLX), [6-Hydroxy-2-(4-hydroxy-phenyl) benzo [b] thien-3-yl] [4-[2-(1-piperidinyl)-ethoxy] phenyl]-methanone-, hydrochloride (Figure 1) is a selective estrogen receptor modulator (SERM) used in the treatment of osteoporosis in postmenopausal women [1]. Clinically, it is effective in the treatment of breast cancer [2, 3]. Figure 1: Chemical structure of Raloxifene hydrochloride (RLX). Literature survey revealed that RLX was analyzed by HPLC [4–9], Stability-indicating UPLC [10], and several UV-spectrophotometric [11–14] in pharmaceutical formulations. Few methods such as LC-MS-MS [15] and HPLC [16] have been reported for estimation of RLX in biological samples. Although the RP-HPLC and UPLC procedures are accurate and effective means of assaying RLX, they are time and solvent consuming, and therefore, disadvantageous for serial estimation for a large number of samples [17]. However, the prominent application of HPTLC is that many samples can be run simultaneously using a small quantity of mobile phase unlike HPLC, thus reducing the analysis time and cost per analysis. In-reverse phase chromatography, polar mobile phase is used and the stationary phase is nonpolar. It is increasingly being experienced that different components of formulation which could not be resolved using normal-phase TLC could easily be
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