A Simple Stability Indicating Method Development and Validation for the Simultaneous Estimation of Naloxone Hydrochloride and Buprenorphine Hydrochloride in Pharmaceutical Dosage Forms by RP-HPLC

A reverse phase high performance liquid chromatographic (RPHPLC) method has been developed and validated for simultaneous estimation of Naloxone Hydrochloride and Buprenorphine Hydrochloride in pure and marketed formulations. Separation was carried out using column Hypersil ODS C18 (250 mm x 4.6mm x 5μm particle size) in isocratic mode using mobile phase composition pH 6.0 ammonium acetate Buffer: Acetonitrile (68:32)v/v and UV detection at 310 nm. The compounds were eluted at a flow rate of 1.0 mL/ min. The average retention times for Naloxone and Buprenorphine were 2.86 and 3.67 min, respectively. The method was validated according to the ICH guidelines. The %RSD of all validation parameters found to be less than 2% indicating high degree of accuracy and precision of the proposed HPLC method. The method was linear over the concentration of 530μg/ml and 20120μg/ml for Naloxone and Buprenorphine respectively. The LOD and LOQ of Naloxone were found to be 0.08μg/mL and 0.26μg/mL and of Buprenorphine were found to be 0.0078μg/mL and 0.0237μg/mL. The drugs were also exposed to acidic, alkaline, oxidative, thermal and photolytic conditions and the stressed samples were analyzed by the proposed method. Degradation studies showed that the both the drugs were highly stable under acidic, oxidative, thermal and photolytic conditions. Under alkaline conditions, RT values were shifted to lower as compared to standard without any additional peaks. The high percentage of stability under stress conditions confirms the suitability of the method for simultaneous estimation of Naloxone Hydrochloride and Buprenorphine Hydrochloride in pure and marketed formulations. K. Kalyani 1 *, V. Anuradha 2 , S.Vidyadhara 3 , RLC.Sasidhar 3 TNV. Ganesh Kumar 3 1.Department of Chemistry, R.V.R & J.C College of Engineering, Guntur, A. P, India. 2.Vignan’s Nirula Institute of Technology and Science, Guntur, A.P., India 3. Chebrolu Hanumaiah Institute of Pharmaceutical Sciences, Guntur, A.P., India. Submission: 3 June 2016 Accepted: 7 June 2016 Published: 25 June 2016 www.ijppr.humanjournals.com Citation: K. Kalyani et al. Ijppr.Human, 2016; Vol. 6 (3): 206-222. 207 INTRODUCTION Naloxone hydrochloride (NAH) is chemically known as Morphinan-6-one, 4, 5-epoxy-3, 14dihydroxy-17-(2-propenyl), Hydrochloride. The empirical formula of NAH is C19H22ClNO4 and the molecular weight is 363.835 (Fig. I). It occurs as a white to slightly off-white powder, and is soluble in water, in dilute acids, and in strong alkali; slightly soluble in alcohol, insoluble in ether and in chloroform. It is a potent opioid antagonist and is a competitive antagonist at mu, delta and kappa opioid receptors. Naloxone is synthesized from thebaine. The chemical structure of naloxone resembles that of oxymorphone, the only difference being the substitution of the Nmethyl group with an allyl (prop-2-enyl) group. The name naloxone has been derived from Nallyl and oxymorphone[1-4]. Fig: I Structure of Naloxone Hydrochloride Buprenorphine hydrochloride (BUH) is chemically known as (6R, 7R, 14S)17cyclopropylmethyl-7, 8-dihydro-7-[(l S)-1-hydroxy-1, 2, 2trimethylpropyl]-6-0-methyl-6, 14ethano-17-normorphine hydrochloride. The molecular formula of BUH is C29H42ClNO4 and the molecular weight is 504.1 (Fig.II). Buprenorphine hydrochloride is a white or off-white crystalline powder, weakly acidic and sparingly soluble in water, freely soluble in alcohols and practically insoluble in cyclohexane. It is a potent semi-synthetic opiate analgesic with a potency of 20-40 times higher than that of morphine [5]. BUH is a clear, sterile, injectable agonistantagonist analgesic intended for intravenous or intramuscular administration successfully or sublingual routes for the treatment of moderate to severe pain as well as chronic pain [6]. Thus BUH is given in combination with antagonist NAH. A few examples of combinatorial dosage forms of BUH and NAH currently available in the market in different dosage forms by their trade names are SUBOXONE [7]. www.ijppr.humanjournals.com Citation: K. Kalyani et al. Ijppr.Human, 2016; Vol. 6 (3): 206-222. 208 Fig: II Structure of Buprenorphine Hydrochloride Literature survey reveals that there were number of analytical methods available for both the drugs alone or in combination with other drugs including spectroscopy, chromatographic methods such as gas chromatography with electron-capture or mass spectrometry detection and HPLC with fluorescence electrochemical or mass spectrometry detection [8-13] are reported, but there is no method established for the stability indicating RP-HPLC under stress for this combination. The present work describes the development of stability indicating RP-HPLC method, which can quantify these components simultaneously from a combined dosage form. The present RP-HPLC method was validated [14-15] and applied under stressed conditions according to (ICH) guidelines. ICH has made the mandatory need of developing stability indicating assay methods for every drug candidates. Stability indicating assay methods helps in establishing the inherent stability of the drug which provides assurance on detection changes in identity, purity and potency of the product on exposure to various conditions [16]. So an attempt has been made to develop a method under stress conditions like acidic, basic, thermal, photolytic and oxidative, this which in turn can help in establishing the degradation pathways and the intrinsic stability of the molecules. The object of the present work was to develop a stability indicating method for the simultaneous estimation of Naloxone hydrochloride and Buprenorphine hydrochloride. www.ijppr.humanjournals.com Citation: K. Kalyani et al. Ijppr.Human, 2016; Vol. 6 (3): 206-222. 209 MATERIALS AND METHODS