METHOD DEVELOPMENT AND VALIDATION OF RIFAMPICINE AND PIPERINE IN THEIR COMBINED DOSAGE FORM KAUSHIK G. KAPURIYA* 1, PRAKASH M. PARMAR 1, HIRAL R. TOPIYA 1, SHITAL D. FALDU 1 ABSTRACT The RP-HPLC method has been developed for simultaneous estimation of Rimfapicin And Piperine in Their Combined Dosage Form. For RP-HPLC method all the standard and sample solutions were prepared in Methanol: Acetonitrile. A stability indicating reversedphase HPLC method has been developed and subsequently validated for simultaneous estimation of Rimfapicin and Piperine in their combination product. The proposed RP-HPLC method utilizes a Hypersil BDS C18 (25cm x 4.6mm, 5 μm) column, mobile phase consisting of Buffer and Acetonitrile in the proportion of 55 : 45 (v/v) with apparent ph adjusted to 6.8, and UV detection at 341 nm.. The described method was linear over a range of 8-24 μg/ml for Rifampicin and 0.4-1.2 μg/ml for Piperine. The mean recoveries were 99.91 and 100.53% for Piperine and Rifampicine, respectively. Validations of the proposed method were carried out for its accuracy, precision, linearity and range, specificity, LOD and LOQ according to ICH guidelines. The method was validated by evaluation of different parameters. The method has been successfully applied for the analysis of drugs in pharmaceutical formulation. KEYWORDS Reverse Phase High Performance Liquid Chromatography, Rifampicine and Piperine. AFFILIATION 1. *Mr. Kaushik G. Kapuriya, Assistant Professor, Smt. R. D. Gardi B. Pharmacy College. Nyara, Dist: Rajkot, 360110, Gujarat, India. 2. Prakash M. Parmar, Research Scholar, RDGPC, Nyara, Rajkot, Gujarat, India. 3. Ms. Hiral R. Topiya, Assistant Professor, RDGPC, Nyara, Rajkot, Gujarat, India. 4. Dr. Sheetal Faldu, Principal, RDGPC, Nyara, Rajkot, Gujarat, India. 5. *Author for correspondence: Mob no: 7600027116, email: kkapuriya@gmail.com 71
INTRODUCTION Rifampicin (RIFA) is a well known Anti-Tuberculosis drug. 1 Methods for Estimation of Rifampicin is official in IP 2, BP 3 and USP 4. Literature survey reveals HPLC 5, HPTLC 6 and Visible Spectrophotometry methods 7 for determination of RIFA in single and RP-HPLC, 8, 9 Visible Spectrophotometry 10,11 and HPTLC 12 methods in combined pharmaceutical dosage forms as well as in biological fluids. Piperine (PIPE) is a natural alkaloid which is used as Bio enhancer 13. Piperine is official in IP 14. Literature survey reveals RP-HPLC 15, UV Spectrophotometry and HPTLC method for the determination of Piperine in single and in combination with other drugs. The combined dosage forms of RIFA and PIPE along with Isoniazid are available in the market and used as anti tuberculosis drugs. The simultaneous estimation of Rimfapicin and Piperine in their combined dosage form is not official in any pharmacopoeia; hence no official method is available for the estimation of RIFA and PIPE in their combined dosage forms. Literature survey reveals simple spectrophotometric method for simultaneous estimation of RIFA and PIPE in combined dosage forms. Literature survey may not reveal any RP-HPLC for the estimation of RIFA and PIPE in their combined dosage form. The proposed RP HPLC method was found to be sensitive, accurate and precise for determination of RIFA and PIPE in capsule dosage form. The method utilizes easily available and cheap solvent for analysis of RIFA and PIPE hence the method was also economic for estimation of RIFA and PIPE from capsule dosage form. Hence it can be conveniently adopted for routine quality control analysis of the drugs in combined pharmaceutical formulation. Apparatus and instruments EXPERIMENTAL SECTION The HPLC system (Shimadzu VP, Japan), consisted of a system controller (SCL-10A VP ), online degasser (DGU-14A), low-pressure gradient flow control valve (FCV-10AL VP ), solvent delivery module (LC-10AD VP ), auto injector (SIL-10 AD VP ), column oven (CTO-10A VP ), UV VIS and PDA detector (SPD-10A VP ) and CLASS VP software version 6.14 SP1. Sonicator (5510, Branson Ultrasonics Corporation, USA) was used in the study. Material RIFA and PIPE bulk powder was gifted by Cadila Pharmaceuticals Ltd. Dholka, Ahmadabad, and Gujarat, India. The commercial fixed dose combination product was procured from the local market. All other reagents used were of HPLC grade. Method Development and Optimization Selection of detection wavelength The standard solution of Rifampicin and Piperine were scanned over the range of 200 nm to 400 nm wavelengths. The overlay spectra were recorded and the intersection point 72
wavelength was selected. It was observed at 341 nm. So the wavelength, 341 nm, was selected for the determination of Rifampicin and Piperine. Selection of mobile phase The mobile phase was selected on the basis of best separation, peak purity index, peak symmetry, theoretical plate etc. So no. of trials was taken for the selection of mobile phase. Generally As per I.P 2007 method for Rifampicin and various combination of Rifampicin, a combination of Buffer (1.4 gm Disodium Hydrogen Orthophosphate in 1000 ml water, ph 6.8 adjusted with dilute Phosphoric acid) with Acetonitrile was used as Mobile phase. So also for this combination of Rifampicin and Piperine, the same mobile phase in different ratio was used to optimize best result. Also different solvent mixtures were used to optimize best result. Selection of ph In mildly basic aqueous solutions (ph 8.2, 20-22 C) in the presence of air, Rifampicin is converted to rifampin quinine. Under basic conditions Rifampicin undergoes desacetylation at 22 C forming the 25-desacetylrifampin. Rifampicin decomposes rapidly in acidic or alkaline conditions at 25 C but slowly in neutral conditions so it is best to prepare aqueous solutions with oxygen-free solvent and at neutral ph. So ph 6.8 was adjusted with dilute Phosphoric acid. Selection of column For HPLC, various columns are available, but C 18 column was preferred over other columns. Hypersil BDS C 18 column (250 mm x 4.6 mm i.d., 5 µm particle size) was chosen to give good peak shape, good lifetime and high resolution compared to other C 18 columns. Selection of column temperature The column temperature (30 C) has minimized variation of retention and made the peak sharp. It has also shortened the run time. Chromatographic Conditions - Column Hypersil BDS C18 (25cm x 4.6mm, 5 μm) - Column temp. - 25ºC - Sample temp. - 10ºC - Buffer- 1.4 gm Disodium Hydrogen Orthophosphate in 1000 nl water, ph 6.8 adjusted with dilute Phosphoric acid - Mobile Phase - Buffer : Acetonitrile (55 : 45) - Solvent Mixture - Methanol : Acetonitrile ( 50 : 50 ) - Standard Solution - (A) Piperine 50 mg dissolve and dilute upto 100 ml with solvent mixture 73
- (B) 20 mg Rifampicin Dissolve in 70 ml Solvent mixture 2 ml solution A Dilute up to 200 ml with solvent mixture (Rifampicin 100 μg/ml & Piperin 5 μg/ml) - Flow Rate 1.5 ml per minute - Detector Condition 341 nm - Injection Volume 20 μl Buffer Preparation Dissolve 1.42 g of disodium hydrogen phosphate anhydrous in 1000 ml of water. Adjust ph to 6.8 with orthophosphoric acid. Diluent Prepare filtered and degassed mixture of methanol and acetonitrile in ratio (50:50). Piperine standard stock preparation: Accurately weigh and transfer 50.0 mg of Piperine working standard of known potency into 100 ml volumetric flask. Add 70 ml of diluent and sonicate to dissolve. Dilute up to mark with diluents and mix. Standard Solution preparation Accurately weigh and transfer 20.0 mg of Rifampicin working standard of known potency into 200 ml amber colored volumetric flask and add 70 ml of diluent. Sonicate to dissolve, add 2.0 ml of Piperine standard stock solution and make up to mark with diluent and mix. Figure 1. Chromatograph of standard RIFA and PIPE Table 1. Data for system suitability test for Rifampicin and Piperine Parameters Rifampicin ± RSD (n = 6) Piperine ± RSD (n = 6) Retention time (min) 2.75 ± 0.1% 8.11 ± 0.2% Tailing factor 1.1 ± 0.3% 1.0 ± 0.6% 74
Theoretical plates 5631 ± 0.7% 13218 ± 0.8% Assay Preparation Area 1922490 ± 0.5% 480780 ± 0.2% Resolution 8.93 ± 0.8% Weigh 20 capsules and determine average net content of blend. Reserve Isoniazid tablet for assay of Isoniazid. Accurately weigh and transfer quantity of capsule contents equivalent to about 200.0 mg of Rifampcin into 200 ml amber colored volumetric flask. Add 100 ml of diluent and sonicate for about 20 minutes. Dilute to volume with diluent and mix. Filter resulting solution with 0.45 μm PVDF filter discarding first few ml of filtrate. Further dilute 5.0 ml of this solution to 50.0 ml with diluents and mix. Chromatographic Parameters Liquid chromatograph is equipped with PDA detector or variable wavelength UV detector, an injector and data processor. - Column Hypersil BDS C18 (25cm x 4.6mm, 5 μm) - Column temperature - 25ºC - Sample temperature - 10ºC - Flow Rate 1.5 ml per minute - Detector Condition 341 nm - Injection Volume 20 μl - Retention time Rifampicin: About 3.5 minutes. Selection of Wavelength Piperine: About 7.0 minutes. RESULTS AND DISCUSSION The detection was carried out in the UV region and wavelength selected for detection was 341 nm in mobile Phase. Validation of RP-HPLC Method As per the ICH guidelines 16, the method validation parameters checked were linearity, accuracy, precision, limit of detection, limit of quantitation. Linearity and Range The linearity of the method was determined for the formulation at five concentration levels ranging from 8 to 24 μg/ml for RIFA and 0.4-1.2 μg/ml PIPE. The equation for regression 75
Average area Average area International Bulletin of Drug Research., 1(2): 71-80 line was y = 23308X-1898.2 (R2= 1) for RIFA and y = 105066X-372.4 (R2= 0.999) for PIPE. Linearity of Rifampicin 600000 500000 y = 23308x - 1898.2 R 2 = 1 400000 300000 200000 area Linear (area) 100000 0 0 10 20 30 Concentration Figure 4. Calibration curve for Rifampicin 140000 120000 100000 80000 60000 40000 20000 0 Linearity of Piperine y = 105066x - 372.4 R 2 = 0.9999 area Linear (area) 0 0.5 1 1.5 Concentration Figure 5. Calibration curve for Piperine Table 2. Linearity of Rifampicin and Piperine by RP-HPLC method Linearity level Concentration (µg/ml) Mean area (n=3) Rifampicin Piperine Rifampicin Piperine Level-1 (50%) 8 0.4 184338 41536 Level-2 (75%) 12 0.6 278440 62432 Level-3 (100%) 16 0.8 370801 84311 76
Level-4 (125%) 20 1.0 463716 104607 Level-5 (150%) 24 1.2 557862 125514 Correlation coefficient 1.0000 0.9999 Slope of regression line 23308.1 105065.5 Y-intercept -1898.2-372.4 The results show that an excellent correlation exists between response factor and concentration of drugs within the concentration range indicated above. Accuracy and Precision The accuracy of the method was determined by recovery experiments. The recovery studies were carried out at three levels of 50, 100 and 150% and the percentage recovery was calculated and presented in Table 3. Table 3. Recovery studies of Rifampicine (RIFA) and Piperine (PIPE) Level of % Recovery % Mean Recovery % RSD RIFA PIPE RIFA PIPE 50 100.1 99.97 0.14 0.12 100 100.2 100.1 0.18 0.23 150 100.1 100.2 0.16 0.24 Table 4. Intraday precision data for analysis of Rifampicin and Piperine Drug Concentration (μg/ml) Mean area ± RSD 50 1153497 ± 0.054 Rifampicin 100 2320522 ± 0.049 150 3491052 ± 0.051 2.5 260639 ± 0.071 Piperine 5 529052 ± 0.056 7.5 788648 ± 0.062 77
Table 5. Interday precision data for analysis of Rifampicin and Piperine Drug Concentration (μg/ml) Mean area ± RSD 50 1152086 ± 0.153 Rifampicin 100 2318678 ± 0.078 150 3490432 ± 0.172 2.5 260608 ± 0.108 Piperine 5 528969 ± 0.080 7.5 788593 ± 0.184 RSD value ranges for Rifampicin it is 0.049 0.054% for intraday, 0.078 0.172% for interday and for Rifampicin is 0.056 0.071% for intraday, 0.080 0.184% for interday. The results obtained accurately fall within the limit of acceptance criteria. Hence, the method can be termed as precise. Limit of detection and limit of qualification The limit of detection (LOD) and limit of quantification (LOQ) were calculated using signalto-noise (i.e. 3.3 for LOD and 10 for LOQ) ratio using following equations designated: LOD = 3.3 Χ σ/s LOQ = 10 Χ σ/s Where, σ = the standard deviation of the response, S = slope of the calibration curve. LOD and LOQ for Rifampicin are found to be 0.498 µg/ml and 1.51µg/ml respectively. LOD and LOQ for Piperine are found to be 0.081 µg/ml and 0.246 µg/ml. CONCLUSION From the results obtained, it is obvious that the proposed method is applicable for the determination of Rifampicin and Piperine without interference and with good sensitivity. The results obtained indicate that the proposed method for the estimation of Rifampicin and Piperine is simple, specific, rapid, linear, accurate, precise, robust, sensitive and suitable for intended use. These merits suggest the use of the proposed method in routine and quality control analysis of Rifampicin and Piperine without interference from commonly encountered excipients and additives. 78
REFERENCES 1. Sweetman SC. The Martindale: The Complete Drug Reference. 35th ed. Pharmaceutical Press. London, UK: 2007. p. 290. 2. Indian Pharmacopoeia, Vol. III, New Delhi, The Controller Publication, Govt. of India; 2010: 2054-2065. 3. British Pharmacopoeia, Vol. II, London, The British Pharmacopoeia Commission; 2010: 1844, 3063. 4. The United State Pharmacopoeia, USP28 NF23, Rockville MD, United State Pharmacopoeial Convention, Inc; 2005: 3501 3507. 5. Panchagnula R, Sood A, Sharda N, Kaur K, Kaul CL, Determination of rifampicin andits main metabolite in plasma and urine in presence of pyrazinamide and isoniazid by HPLC method. Journal of Pharmaceutical and Biomedical Analysis 1999; 18: 1013 1020. 6. Shishoo CJ, Shah SA, Rathod S, Savale SS, Vora MJ. Impaired bioavailability of rifampicin in presence of isoniazid from fixed dose combination (FDC) formulation. International Journal of Pharmaceutics 2001; 228: 53 67. 7. Mariappan TT., Jindal KC. Saranjit Singh, Overestimation of rifampicin during colorimetric analysis of antituberculosis products containing isoniazid due to formation of isonicotinyl hydrazone. Journal of Pharmaceutical and Biomedical Analysis, November 2004; 36: 905 908. 8. Khuhawar MY, Rind FMA. High performance liquid chromatographic determination of isoniazid, pyrazinamide and rifampicin in pharmaceutical preparations, Pakistan journal of pharmaceutical sciences.1998; 18: 49-54. 9. Calleri E, Furlanetto S, Massolini G, Caccialanza G. Validation of a RP-LC method for the simultaneous determination of isoniazid, pyrazinamide and rifampicin in a pharmaceutical formulation, Journal of Pharmaceutical and Biomedical Analysis. 2002; 29:1089 1096. 10. Manna A, Ghosh I, Datta S, Ghosh PK, Ghosh LK, et al. Simultaneous Estimation Of Rifampicin And Isoniazid In Combined Dosage Forms, Indian journal of pharmaceutical sciences, 2000; 62: 185-186. 11. Goyal P, Pandey S, Udupa N. Simultaneous Spectrophotometric Estimation Of Isoniazid And Rifampicin From Combined Dosage Forms. Indian journal of Pharmaceutical sciences, 2002; 64; 76-78. 12. Ali J,. Ali N, Sultana Y. et al. Development and validation of a stability-indicating HPTLC method for analysis of antitubercular drugs. Acta Chromatographica, 2007; 18: 168-179. 79
13. Atal CK, Dubey RK, Singh J. "Biochemical basis of enhanced drug bioavailability by piperine: evidence that piperine is a potent inhibitor of drug metabolism. J. Pharmacol. Exp. Ther. 1985; 232 (1): 258 62. 14. Indian Pharmacopoeia, Vol. III, New Delhi, The Controller Publication, Govt. of India; 2010: 2522, 2530-31. 15. Wood B., Maureen L. Barrow, James DJ. Piperine determination in pepper (Piper nigrum L.) and its oleoresins a reversed-phase high-performance liquid chromatographic method, Flavour and Fragrance Journal. 1988; 3(2): 55 64. 16. The International Conference on Harmonization, Q2 (R1), Validation of Analytical Procedure: Text and Methodology. 2005. 80