Etodolac Containing Topical Niosomal Gel: Formulation Development and Evaluation

Abstract

The present study aimed to investigate the delivery potential of Etodolac (ETD) containing topical niosomal gel. Niosomal formulations were prepared by thin film hydration method at various ratios of cholesterol and Span 60 and were evaluated with respect to particle size, shape, entrapment efficiency, and in vitro characteristics. Dicetyl phosphate (DCP) was also added in the niosomal formulation. Mean particle size of niosomal formulation was found to be in the range of 2 μm to 4 μm. Niosomal formulation N2 (1 : 1) ratio of cholesterol and surfactant displayed good entrapment efficiency (96.72%). TEM analyses showed that niosomal formulation was spherical in shape. Niosomal formulation (N2) displayed high percentage of drug release after 24 h (94.91) at (1 : 1) ratio of cholesterol : surfactant. Further selected niosomal formulation was used to formulate topical gel and was characterized with respect to its various parameters such as pH, viscosity, spreadability, ex vivo study, and in vivo potential permeation. Ex vivo study showed that niosomal gel possessed better skin permeation study than the plain topical gel. Further in vivo study revealed good inhibition of inflammation in case of topical niosomal gel than plain gel and niosomal formulation. The present study suggested that topical niosomal gel formulations provide sustained and prolonged delivery of drug.

The Efficacy of Cholesterol-Based Carriers in Drug Delivery

“…Etodolac (ETD) is a non-steroidal anti-inflammatory drug whose application suffers from poor solubility, short half-life and undergoes quick s first pass metabolism when administered orally [ 121 , 122 ]. Asthana et al investigated the potential of loading ETD into a topical niosomal gel for transdermal administration.…”

“…Formulation N 2 with a drug:cholesterol:Span 60 ratio of 1:1:1 had the highest drug entrapment efficiency of 96% ( Table 11 ). The decrease in the drug entrapment efficiency as the amount of cholesterol increased above the ratio of 1 suggests that a competition of cholesterol and the drug for packing space in the bilayer [ 122 ].…”

“…When the content of cholesterol is increased, the content of surfactants decreased and the hydrophobicity of the bilayer membrane increased, thereby increasing the vesicles radius and establishing a thermodynamic stable form. Furthermore, the bilayer membrane displayed a rigid structure due to cholesterol content, which results in reduced size from sonication and a bigger vesicles size [ 122 ].…”

Screening and Optimization of Valacyclovir Niosomes by Design of Experiments

“…Valacyclovir loaded niosomes were prepared using thin film hydration method [19][20][21]. Span 60 and cholesterol in different ratios were dissolved in 10 ml of chloroform and methanol mixture (2:1 v/v) in a round bottom flask.…”

“…This may be due to two possible reasons, firstly with an increase in cholesterol, the hydrophobicity of bilayer vesicles increases, thereby decreasing vesicle permeability. Secondly higher cholesterol content may compete with the drug molecules for packing space within the bilayer, thereby excluding the drug as amphiphiles [20,21]. …”