International Journal of Research in Pharmacy and Biosciences Volume 1, Issue 1, November 2014, PP 15-22 ©IJRPB www.ijrpb.org 15 Stability-Indicating HPLC Method for Determination of Nalbuphine Hydrochloride Khalid A. Attia, Mohammed W. Nassar, Ahmed El-Olemy* Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Al-Azhar University, Nasr City, Cairo, Egypt * ahmed_olemy2000@yahoo.com Abstract: A simple, sensitive, stability-indicating HPLC method was developed and validated for the quantitative determination of nalbuphine hydrochloride in presence of its degradation product.The analysis was carried out on a BDS Hypersil C18 ( 250 X 4.6 X 5μm particle size) using a mobile phase consisting of 5 mM sodium acetate buffer; pH 5.5: acetonitrile (40:60, v/v). The analysis was performed at ambient temperature with a flow rate of 1 ml/min and UV detection at 210 nm. The method showed good linearity over the concentration range of 1-15 μg/ml with a lower detection limit of 0.243 and quantification limit of 0.737 μg/ml. The proposed method can selectively analyse the drug in presence of up to 87% of its oxidative degradate with mean recovery± RSD% of 100.08±0.678.The method was validated and successfully applied for determination of nalbuphine in its commercial preparation and the obtained results were statistically compared with those of the reported method by applying t-test and F-test at 95% confidence level and no significant difference was observed regarding accuracy and precision. Keywords: Stability-indicating, nalbuphine, HPLC, internal standard, validation. 1. INTRODUCTION Nalbuphine hydrochloride (Figure 1) is ( ฀ ฀ - Cyclobutylmethyl)- 4,5-epoxymorphinan-3,6,14- triol hydrochloride [1].It is a phenanthrene derivative opioid analgesic.It has mixed opioid agonist and antagonist activity.It is used for the relief of moderate to severe pain, including that associated with myocardial infarction, and as an adjunct to anaesthesia [2]. Figure 1. Structural formula of nalbuphine hydrochloride Few analytical methods have been reported for its analysis including spectrophotometric[3-5], spectrofluorimetric [5,6], electrochemical [7 ]and chromatographic methods [8-14] . High performance liquid chromatography (HPLC) is an important qualitative and quantitative technique, generally used to separate, identify, and quantify the active compounds in pharmaceutical and biological samples [15].It is the most versatile, safest, dependable and fastest chromatographic technique for the quality control of drug components [16]. The main purpose of this work is to establish a sensitive, accurate and precise stability-indicating reversed phase HPLC procedure for the determination of nalbuphine in bulk powders and in pharmaceutical preparation in the presence of its degradation product.