Emmanuel M Uronnachi,
John DN Ogbonna ,
Franklin C Kenechukwu,
Salome A Chime,
Anthony A Attama,
Vincent C Okore
Drug Delivery Research Unit, Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, 410001, Nigeria;
For correspondence:- John Ogbonna
Email: johnixus@yahoo.com Tel:+2348063674303
Received: 2 February 2013
Accepted: 3 January 2014
Published: 20 February 2014
Citation:
Uronnachi EM, Ogbonna JD, Kenechukwu FC, Chime SA, Attama AA, Okore VC.
Formulation and Release Characteristics of Zidovudine-Loaded Solidified Lipid Microparticles. Trop J Pharm Res 2014; 13(2):199-204
doi:
10.4314/tjpr.v13i2.5
© 2014 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..
Abstract
Purpose: To formulate and determine the release profile of zidovudine (AZT)-loaded solidified lipid microparticles (SLMs).
Methods: Different concentrations (0, 1, 2, 3 and 5 %w/w) of zidovudine (AZT) were formulated into microparticles in melt dispersion of Phospholipon® 90H and goat fat in the ratio 1:1, 2:1, 2:3 and 1:3 followed by lyophilization. They were characterized for particle size, yield, entrapment efficiency (EE) and loading capacity (LC). In vitro release kinetics and mechanism of release were assessed sequentially in simulated gastric fluid (SGF, pH 1.2)and simulated intestinal fluid (SIF, pH 7.2).
Results: The ratio 1: 1 formulation was the most stable in terms of physical observation.. Particle size analysis indicated that the particles were irregular in shape with size ranging from 5.10 ± 0.10 to 13.40 ± 2.20 µm. Yield decreased with increase in drug concentrations in the SLMs formulations. EE data showed that the microparticles containing 1 % w/w of AZT had the highest entrapment efficiency of 74.0 ± 0.03 %. LC also decreased with increase in concentration of AZT. AZT tablet released most of its content within 5 min with a sharp decrease in the concentration but the SLMs maintained its release for 8 to 12 h in different batches.
Conclusion: The results show that drug content has influence on drug release from the SLMs, but not on the mechanism of release. Furthermore, dose dumping was avoided and drug release mechanism was mostly non-Fickian while for the reference (commercial) tablet, it was Fickian.
Keywords: Phospholipon® 90H, Solidified lipid microparticles, Solidified reverse micellar microparticle, Zidovudine