A Validated RP- HPLC Method for Estimation of Risperidone in Oral Solution

S. Kathirvel and A. Suneetha*.

Hindu College of Pharmacy, Amaravathi Road, Guntur-500 002, A.P, India

ABSTRACT:

A simple, rapid, sensitive and precise HPLC method has been developed for the estimation of risperidone in oral solution. In this method RP-C₁₈ Phenominex Gemini column (250 mm x 4.6 mm i.d.,5µm particle size) with mobile phase consisting of 0.5% ammonium acetate buffer, acetonitrile and methanol in the ratio of 50:20:30 v/v/v in isocratic mode was used. The detection wavelength is 260 nm and the flow rate is 1.5 mL/min. In the range of 20-100µg/mL, the linearity of risperidone shows a correlation coefficient of 0.9999. The percentage recovery ranges from 98.95-101.50%. The proposed method was validated by determining sensitivity, accuracy, precision and linearity.

KEYWORDS: Risperidone, HPLC, Oral solution,Validation

INTRODUCTION:

Risperidone (RISP) is belonging to the chemical class of benzisoxazole derivatives and chemically, it is 4-[2-[4-(6- fluorobenzo[d]isoxazol-3-yl)-1-piperidyl] ethyl]-3-methyl-2, 6 diazabicyclo [4.4.0] deca-1, 3-dien-5-one with molecular formula C₂₃H₂₇FN₄O₂and CAS number 106266-06-2¹, Risperidone is official in BP 2007². Risperidone is atypical psychotropic agent and used as an antipsychotic for bipolar disorder, borderline personality disorder, drug intoxication, brief drug-induced psychosis, and other schizophreniform and psychiatric disorder. Risperidone is mostly metabolized by alicyclic hydroxylation and oxidative N-dealkylation³. Literature review for risperidone analysis revealed several methods based on different technique, such as; visible spectrophotometric methods⁴, LC-MS and HPLC-ESI/MS assay for its quantification in plasma and serum^5-7, Chiral Chromatography⁸, Pulse polarography⁹, Chemiluminescence’s assay¹⁰and LC with Coulometric Detection¹¹. A few HPLC methods ^12-14 were also reported for the estimation of risperidone in tablet dosage form. However no method was reported for the estimation of risperidone in oral solution. The present work describes a simple, rapid, sensitive, accurate and precise HPLC method for the determination of risperidone in bulk as well as in oral solution.

CHROMATOGRAPHIC CONDITIONS:

The separation was carried out on isocratic HPLC system (Shimadzu) with Shimadzu Binary HPLC Pump, Shimadzu LC-20 AT UV-Visible Detector, Spinchrom software and RP-C₁₈ Phenominex Gemini column (250 mm x 4.6 mm i.d., 5µm particle size). The mobile phase consisting of 0.5% ammonium acetate buffer, acetonitrile (HPLC grade) and methanol (HPLC grade) were filtered through 0.45µ membrane filter before use, degassed and were pumped from the solvent reservoir in the ratio of 50:20:30 v/v/v in to the column at the flow rate of 1.5ml/min. The detection was monitored at 260 nm and the run time was 7 min. The volume of injection loop was 20µL prior to injection of the drug solution. The column was equilibrated for at least 0.5h with the mobile phase flowing through the system.

PROCEDURE:

Stock solution of risperidone was prepared by dissolving 50 mg of risperidone in 50 mL standard volumetric flask containing 50 mL of mobile phase. 5 mL of the above solution was transferred to 50 mL volumetric flask and the volume was made up to the mark with mobile phase. Subsequent dilutions of this solution were made with mobile phase to get concentration of 20-100µg/mL. The solutions were injected into the 20µL loop and the chromatogram was recorded. The calibration curve was constructed by plotting concentration vs. peak area ratio (fig.-2). The linearity experiment was carried out in triplicate to ascertain accuracy and precision of the method.

ASSAY:

Five milliliter of risperidone oral solution (Sizodon, 1mg/mL) was transferred in to 50 mL standard volumetric flask. About 30 mL of mobile phase was added and kept in ultrasonic bath for 5 min. This solution is filtered through a membrane filter and the volume was made up to the mark with mobile phase. From this solution, further dilution was made with the mobile phase to the working concentration range of calibration curve. 20µL of the sample solution was injected under the chromatographic conditions and the chromatograms were recorded. The amount of risperidone present in oral solution was determined by comparing the peak area from the standard.

VALIDATION OF PROPOSED METHOD:

Selectivity of the method was assessed on the basis of elution of risperidone using the above mentioned chromatographic conditions. To study the accuracy, precision, reproducibility of the proposed method, recovery studies were done at three different levels. The pre-analyzed samples were spiked with 80%, 100% and 120% of the standard risperidone and the mixtures were reanalyzed by the proposed method. The estimation was made in triplicate. Percentage recovery was calculated from the amount of drug found in the solution. The results are presented in Table-2. Precision was ascertained by the determination of intra-day and inter-day variabilities and the %RSD was found to be less than 2.0, which indicates that the method is more precise.

RESULTS AND DISCUSSION:

By applying the proposed method, the retention time of risperidone was found to be 4.2 min (Fig.1). Linearity range was observed in concentration range range of 20-100µg/mL. The regression equation of risperidone was found to be Y=12.401X-9.1(r=0.9999) where Y is the peak area ratio and X is the concentration of risperidone (µg/mL). The asymmetry factor was found to be 1.091, which indicated asymmetric nature of peak. The number of theoretical plates was found to be 8661, which indicates efficient performance of the column. The limit of detection and limit of quantification found to be 0.47 and 1.43µg/mL respectively, indicates the sensitivity of the method. The recovery of risperdione was found to be 99.7%, which indicates that the proposed method is free from interference of the excipients used in oral solution. The system suitability parameters were shown in Table-1. The proposed liquid chromatographic method was applied for the determination of risperidone in oral solution (SIZODON) and the results are presented in Table-2.

Figure.1: Standard Chromatogrm of Risperidone

Table 1: Validation Summary

System Suitability

Results

Linearity range (µg/mL)

Correlation Coefficient

Asymmetry factor

Theoretical plates (N)

LOD (µg/mL)

LOQ (µg/mL)

Percentage recovery

20-100

0.9999

1.091

8661

0.47

1.43

99.7

Figure.2: Linearity Curve of risperidone

Table 2: Assay and Recovery Studies

Formulation (mg/ml)

Label claim (mg/ml)

Amount found

Amount found *(%)

Recovery (%)

RSD (%)

Brand name

(SIZODON)

0.9898

98.98

99.7

0.601

*Mean of five determinations.

CONCLUSION:

The proposed HPLC method was found to be highly accurate, sensitive and precise. Therefore this method can be applied for the routine quality control analysis of risperidone in oral solution.

REFERENCES:

1. The Merck Index, Merck& Co., Inc., White House Station, New Jersy. 2001.

2. British Pharmacopoeia, Medicines and Healthcare Products Regulatory Agency M.H.R.A. 2007.

3. K.D. Tripathi, Essentials of Medical Pharmacology, Jaypee Brothers, Medical Publishers, New Delhi. 2003.

4. I. Singhvi and A. Goyal, “Visible spectrophotometric determination of risperidone in tablet formulations” accessed on http://www.pharmainfo.net on 25/04/08.

5. Z. Zhou, L. Xin, L. Kunyan , X. Zhihong, C. Zeneng, P. Wenxin, F. Wang, R. Zhu and L. Huande, Journal of Chromatography B. 802; 2004: 257.

6. M.G. Bartlett, G. Zhang, and A.V. Terry. Journal of Chromatography B. 856; 2007: 20.

7. G. Subbaiah, S. Singh and J. Bhatt, Rapid Communications in Mass Spectrometry, 20; 2006: 2109

8. C. Danel, C. Barthelemy, D.Azarzar, H. Robert, J.P. Bonte, P.Odou and C. Vaccher, Journal of Chromatography A. 1163; 2007: 228.

9. A. Joshi, C. Jeyaseelan and Jugade R Croat. Chem. Acta., 79; 2006: 541.

10. Z. Song and S C. Wang, Journal of Pharmaceutical Biomedical Analysis. 36; 2004: 491.

11. D.S.Schatz and A. Saria, Pharmacology, 60; 2000: 51.

12. S.L .Baldaniya, K.K. Bhatt, R.S .Mehta and D.A. Shah, RP- HPLC Estimation of Risperidone in tablet dosage form. Indian Journal of Pharmaceutical Sciences. 70; 2008:494-497.

13. Y. Mohammad, B. Pragati Kumar, Subhani. Development and Validated new RP- HPLC method for the determination of Risperidone in bulk and tablet dosage form. Research Journal of Pharmaceutical Biology and Chemical Sciences. 1(2); 2010: 165- 171.

14. A.P. Suthar, S.A. Dubey, S.R. Patel and A.M. Shah. Determination of risperidone and forced degradation behavior by HPLC in tablet dosage form. International Jornal of PharmTech Research.1(3); 2009: 568-574.

Received on 20.06.2011

Accepted on 12.08.2011

Research Journal of Pharmaceutical Dosage Forms and Technology. 3(4): July-Aug. 2011, 139-141