Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Optimization of a novel oral colon delivery system of indomethacin using full factorial design

Samar A Afifi^1,2, Walaa M Mandour¹, Kadria A Elkhodairy^1,3

¹Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; ²Department of Pharmaceutics, National Organization for Drug Control and Research, Giza; ³Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.

For correspondence:- Kadria Elkhodairy Email: elkhodairy53@yahoo.com Tel:+66543791270

Received: 9 January 2015 Accepted: 12 April 2015 Published: 26 May 2015

Citation: Afifi SA, Mandour WM, Elkhodairy KA. Optimization of a novel oral colon delivery system of indomethacin using full factorial design. Trop J Pharm Res 2015; 14(5):761-768 doi: 10.4314/tjpr.v14i5.3

© 2015 The authors.
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Abstract

Purpose: To develop and optimize indomethacin (IDM) matrix tablets for specific colon drug delivery.

Methods: Indomethacin matrix tablets containing hydrogenated castor oil (HCO), and pectin (PEC) were prepared by hot fusion method. A 3² full factorial design was used to investigate the combined effect of two independent formulation variables, X1 and X2, namely, the amount of HCO and PEC, respectively. Their effect on IDM release from the matrix tablets in acidic medium (0.1 N HCl) and phosphate buffer (pH 6.8), were analyzed and optimized. A contour plot was also applied to graphically represent the effect of the independent variables on drug release in pH 6.8 medium at 2 h (Y1) and 24 h (Y2), and the time required for 25 % drug release (Y3) as dependent variables.

Results: The optimized IDM matrix tablets showed almost total retardation of drug release in acidic medium and prolonged sustained release in pH 6.8 medium over 24 h. The correlation coefficient (R²) value for Y1, Y2 and Y3 were 0.99850, 0.9980 and 0.9970, respectively, indicating good correlation between dependent and independent variables. Differences between the coefficients for Y1, Y2 and Y3 were significant (p < 0.05), and hence contributed significantly to the prediction of the independent variables.

Conclusion: The findings indicate that successful design, development, and optimization of IDM matrix tablets for colon delivery has been achieved.

Keywords: Indomethacin, Hydrogenated castor oil, Pectin, Factorial design, Matrix tablets, Colon delivery system