Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Influence of drug-polymer ratio on physical characteristics and release of metformin hydrochloride from metformin-alginate microspheres

Dewi Melani Hariyadi , Esti Hendradi, Tristiana Erawati, Edlin Nur Jannah, Wenny Febrina

Faculty of Pharmacy, Pharmaceutics Department, Universitas Airlangga, Surabaya, Indonesia;

For correspondence:- Dewi Hariyadi Email: dewi-m-h@ff.unair.ac.id Tel:+62315033710

Accepted: 18 June 2018 Published: 28 July 2018

Citation: Hariyadi DM, Hendradi E, Erawati T, Jannah EN, Febrina W. Influence of drug-polymer ratio on physical characteristics and release of metformin hydrochloride from metformin-alginate microspheres. Trop J Pharm Res 2018; 17(7):1229-1233 doi: 10.4314/tjpr.v17i7.1

© 2018 The authors.
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Abstract

Purpose: To investigate the effect of drug and polymer ratio on the physical characteristics and release rate of metformin hydrochloride from alginate microspheres.

Methods: Microspheres were prepared by ionotropic gelation aerosolization technique using sodium alginate as polymer and calcium chloride as crosslinker. Three formulations of drug and alginate polymer ratios: 1:1 (F1); 1:1.5 (F2); and 1:2 (F3), and 10 % calcium chloride (CaCl₂) were investigated. The microspheres were studied with respect to physical characteristics, release profile and release rate. Release evaluation was done at pH 1.2 in hydrochloric acid (HCl) for 2 h, and in phosphate-buffered saline (PBS) at pH 7.4 for 12 h.

Results: Drug loading in formulations F1, F2 and F3 were 3.08 ± 0.21, 3.34 ± 0.28, and 3.99 ± 0.19 %, respectively. Low entrapment of below 15 % was achieved for all formulations, whereas high yield (above 45 %) was obtained. Drug release above 74 % was observed for all formulations. The release rates of F1, F2 and F3 were 9.6390 x 10-2, 9.0985 x 10^-2, and 8.3312 x 10^-2 %/min, respectively.

Conclusion: Metformin-alginate microspheres can be used for optimized formulations with good physical characteristics and in vitro release. These findings suggest that the microspheres might be a potent drug delivery system for the treatment of diabetic mellitus.

Keywords: Metformin, Alginate microspheres, Drug-polymer ratio, Aerosolization, Drug release