Studies on the Effect of Oil and Surfactant on the Formation of Alginate-Based O/W Lidocaine Nanocarriers Using Nanoemulsion Template

Abstract

The application of various nanocarrier systems was widely explored in the field of pharmaceuticals to achieve better drug encapsulation and delivery. The aim of this study was to encapsulate lidocaine in alginate-based o/w nanocarriers based on the type of oil (i.e., solid or liquid), using a nanoemulsion template prepared by ultrasound-assisted phase inversion temperature (PIT) approach. The nanoemulsion template was initially prepared by dissolving lidocaine in the oil phase and surfactant and alginate in the aqueous phase, and keeping the PIT at around 85 °C, accompanied by gradual water dilution at 25 °C, to initiate the formation of nanoparticles (o/w) with the aid of low frequency ultrasound. The composition and concentration of the oil phase had a major impact on the particle size and led to an increase in the size of the droplet. The lipids that showed a higher drug solubility also showed higher particle size. On the other hand, increasing the concentration of surfactant decreases the size of the droplet before the concentration of the surfactant exceeds the limit, after which the size of the particle increases due to the aggregates that could be produced from the excess surfactant. The method used produced nanoemulsions that maintained nano-sized droplets < 50 nm, over long-term storage. Our findings are important for the design of nanocarrier systems for the encapsulation of lipophilic molecules.

Date Palm Extract (Phoenix dactylifera) PEGylated Nanoemulsion: Development, Optimization and Cytotoxicity Evaluation

“…As well, it was previously revealed that formulations with PDI values smaller than 0.7 are considered perfect and confirm the homogeneity of the particle size in the preparation Danaei et al [39]. It was observable that, increasing oil concentration from 1 to 2 g results in a subsequent increase in the particle size which could be ascribed to the increase in the dispersed phase [40]. Conversely, increasing surfactant concentration could reduce the particle size.…”

Fabrication of Alginate-Based O/W Nanoemulsions for Transdermal Drug Delivery of Lidocaine: Influence of the Oil Phase and Surfactant

“…This appearance indicates a stable formulation with no signs of instability such as creaming, precipitation, or crystallization. This was observed in all of the formulations prepared, wherein the transparency usually indicates the formation of small droplet size [ 26 ]. This was further demonstrated by DLS droplet size measurements.…”

“…This was further demonstrated by DLS droplet size measurements. The mean droplet size was determined for all formulation by placing a sample of each nanoemulsion in the Litesizer without any dilution as they were very diluted (97.5% wt) so the effects of multiple scattering could be avoided [ 26 ]. Droplet size measurements are shown in Figure 1 a, in which most formulations have a mean droplet size below than 150 nm.…”

“…Bees wax and coconut oil, on the other hand, contains polar components such as fatty alcohols and lauric acid, respectively [ 38 , 39 ]. This would lead to a decrease in the interfacial tension resulting in a smaller particle size [ 26 ]. Tween 80 was chosen as the surfactant for the nanoemuslion because it is a non-ionic surfactant that does not irritate the skin when applied transdermally.…”

“…The aim of this work was to study the potential of lidocaine nanoemulsion as a transdermal drug delivery system and to evaluate its extended release profile. The alginate-based O/W nanoemulsion described by Sarheed et al [ 26 ] has been employed as a transdermal delivery system for lidocaine and its release profile has been evaluated and compared to other formulations available in literature. Furthermore, the effect of formulation variables such as oil type, oil concentration and surfactant concentration, has also been studied.…”