In vitro Dynamics of Ibuprofen Incorporated Proniosomal Gel

Abstract

Aim: The research was aimed to encapsulate the ibuprofen with proniosomal gel and facilitate ibuprofen release in sustained manner for sustained drug release. Methods: Different proniosomal gels of ibuprofen were formulated with Span 20/Span 80 and soya lecithin using the method described in literature. In all formulations cholesterol concentration was kept constant. The prepared proniosomal gels were evaluated for chemical incompatibility by FT-IR, vesicle size analysis, encapsulation efficiency, in vitro drug permeation and in vitro drug release kinetics were performed. Results: The principal absorption peaks of ibuprofen were retained in the proniosomal gels indicating that there was no interaction between ibuprofen and excipients. Vesicular diameter markedly depended on the type of the non-ionic surfactant used. As the outer diameter depends on the HLB value of surfactant, the vesicular diameter was less for proniosomes prepared using Span 80 (low HLB). The encapsulation efficiency was more for the proniosomal gels prepared using Span 20. Proniosomal gel prepared using Span 80 showed higher flux across the membrane due to its leaky membrane. The order of ibuprofen release from the proniosomal gel was PN2>PN4>PN1>PN3. Conclusion: The optimized proniosomal gel formulation PN3 containing Span 20 exhibited prolonged ibuprofen release profiles. Fickian diffusion mechanism was observed with the PN3 formulation which was due to the sustained release property. The results indicated that the proniosomal gel would be an effective transdermal delivery system for ibuprofen.

Effect of light irradiation on esterification of oleic acid with ethanol catalyzed by immobilized Pseudomonas cepacia lipase

“…Chowdary and Prapulla studied isovaleric acid esterification in the presence of ethanol catalyzed by Rhizomucor meihei solely with hexane and also with mixed solvents. The reaction was explained using the Ping‐Pong Bi‐Bi mechanism.…”

“…The initial increase and subsequent decreasing trend in the reaction rate with the increase in ethanol concentration indicates that ethanol may act as an inhibitor beyond the critical concentration. Previous researchers also reported the inhibition property of ethanol (ethanol concentration > 0.1 mol/L) in esterification reactions . For instance, Dumont et al and Mendez et al showed that adding excess alcohol to a reaction mixture can affect the alkyl ester yield.…”

“…Many enzyme catalyzed esterification and transesterification reactions follow the Ping‐Pong Bi‐Bi mechanism . The schematic diagram illustrated in Figure represents the Ping‐Pong Bi‐Bi mechanism with competitive inhibition by both alcohol and acid substrates.…”

“…However, the irreversible binding of acid and alcohol to the enzyme active site causes dead‐end inhibition, resulting in a decrease in the reaction rate. The reaction rate equation for this mechanism is given by Equation : where v represents the initial rate; [A] and [B] are concentrations of oleic acid and ethanol, respectively; V max is the maximum rate of reaction; K A and K B are the Michaelis constants for oleic acid and ethanol; and K iA and K iB are the inhibiting constants . The model is applicable under the following assumptions: mass transfer limitation in the reaction system was negligible (both internal and external mass transfer resistance can be ignored); and no loss of enzyme activity throughout the reaction.…”

“…The effect of light irradiation on the kinetics of oleic acid esterification has never been reported, however, the effect of other parameters, such as solvent, pH, temperature, etc., has been well documented. Chowdary and Prapulla investigated the effect of solvent on the kinetic behaviour of the esterification of isovaleric acid with ethanol in the presence of immobilized lipase from Rhizomucor miehei supported on microporous anionic resin. In this report the authors showed that the solvents (hexane and mixed solvent) exhibited almost no effect on the Michaelis constant values of the isovaleric acid (K A ).…”