Mechanism of in vitro release kinetics of flurbiprofen loaded ethylcellulose micropellets.
Flurbiprofen loaded ethylcellulose micropellets with different drug loading were prepared by a quasi-emulsion solvent diffusion technique. Encapsulation parameters of micropellets such as actual drug loading, drug encapsulation efficiency (DEE) and loss of coating polymer (LCP) were determined. Actual drug loading was increased with the increased initial drug loading whereas encapsulation efficiency decreased with the increase of actual drug loading. In vitro drug release profiles of these micropellets were evaluated in distilled water (DW) and also in phosphate buffer solution (PBS) to indicate pH dependency release rates. All the batches of micropellets released about 35-59% in DW and 89-97% in PBS during the period of 8 h and the burst effect of about 50-75% in the first 1.5 h was seen only in PBS. The mechanism of release kinetics was evaluated by fitting the release data to the zero order, first order, Higuchi, Baker-Lonsdale and Peppas equations and also to the differential forms of zero order, first order and Higuchi model. Adequate fitting of release data was found with first order, Higuchi and Peppas models and hence these models were selected for F-test statistics for ascertaining the mechanism of drug release. Higuchi model of drug release in DW and PBS of all the formulations was ruled out due to its significantly different F-value with other models. Thus, mechanism of release of flurbiprofen from ethylcellulose micropellets may be explained by the diffusional exponent model of Peppas et al. as ascertained by F-test statistics rather than the same, based on some other diffusional models even though they have shown good correlation.
Mallick
Subrata
S
Division of Pharmaceutics, Seemanta Institute of Pharmaceutical Sciences, Mayurbahanj, Orissa, India.
Roy
Kunal
K
Chakraborty
Atanu
A
Saha
Subhayu
S
D002214:Capsules; D002482:Cellulose / Q000031:analogs & derivatives / Q000493:pharmacokinetics*; D005480:Flurbiprofen / Q000493:pharmacokinetics*; D010599:Pharmacokinetics
D002214:Capsules; D005480:Flurbiprofen; C013517:ethyl cellulose; D002482:Cellulose