New, Biocompatible, Chitosan-Gelled Microemulsions Based on Essential Oils and Sucrose Esters as Nanocarriers for Topical Delivery of Fluconazole

Abstract

Biocompatible gel microemulsions containing natural origin excipients are promising nanocarrier systems for the safe and effective topical application of hydrophobic drugs, including antifungals. Recently, to improve fluconazole skin permeation, tolerability and therapeutic efficacy, we developed topical biocompatible microemulsions based on cinnamon, oregano or clove essential oil (CIN, ORG or CLV) as the oil phase and sucrose laurate (D1216) or sucrose palmitate (D1616) as surfactants, excipients also possessing intrinsic antifungal activity. To follow up this research, this study aimed to improve the adhesiveness of respective fluconazole microemulsions using chitosan (a biopolymer with intrinsic antifungal activity) as gellator and to evaluate the formulation variables’ effect (composition and concentration of essential oil, sucrose ester structure) on the gel microemulsions’ (MEGELs) properties. All MEGELs were evaluated for drug content, pH, rheological behavior, viscosity, spreadability, in vitro drug release and skin permeation and antifungal activity. The results showed that formulation variables determined distinctive changes in the MEGELs’ properties, which were nevertheless in accordance with official requirements for semisolid preparations. The highest flux and release rate values and large diameters of the fungal growth inhibition zone were produced by formulations MEGEL-FZ-D1616-CIN 10%, MEGEL-FZ-D1216-CIN 10% and MEGEL-FZ-D1616-ORG 10%. In conclusion, these MEGELs were demonstrated to be effective platforms for fluconazole topical delivery.

Development and Optimization of Imiquimod-Loaded Nanostructured Lipid Carriers Using a Hybrid Design of Experiments Approach

“…It also allows the experimental factors to be screened beyond their factorial limits to improve the understanding of their effects on dependent variables. 35 In this study, a total of 20 experiments were generated and their responses are summarized in Table 5 . The results showed that the variations in PS, PDI, and ZP were all best explained by a quadratic model, and the quadratic models for PS, PDI, and ZP were all statistically significant ( p < 0.0001).…”

“…Based on the excipient screening results, the IMQ-NLCs were prepared using STA, OA, polysorbate 80, and stearoyl polyoxyl-32 glycerides based on a hot melt homogenization followed by an ultrasonication method. 35 The BM of lipids consisting of STA and OA was melted at 75 °C followed by the addition of IMQ (3.5% of the BM, w/w) under continuous stirring. Polysorbate 80 and stearoyl polyoxyl-32 glycerides at a 50:50 ratio were dispersed in water and heated separately to 75 °C and added to the BM phase under continuous stirring.…”

Development and Characterization of Azithromycin-Loaded Microemulsions: A Promising Tool for the Treatment of Bacterial Skin Infections

“…In fact, although the water contents of M1 and M2 were similar, M2 exhibited a higher viscosity compared with M1 ( p < 0.05), which can be attributed to its higher surfactant-to-co-surfactant ratio (S mix 2:1 v / v for M1 and S mix 3:1 v / v for M2) [ 36 ]. The obtained values of viscosity could impact the drug release behavior, since it has been reported that formulations characterized by low viscosity allow for an easy drug diffusion through the vehicle [ 37 ]. Although an increase in viscosity is often desired for liquid microemulsions intended for skin application, a low viscosity could have some beneficial characteristics, such as an easier administration via spray systems.…”

“…In fact, M3, bearing the lowest viscosity, provided the release of a greater cumulative amount of the drug after 24 h with respect to M1 and M2 ( p < 0.05). As a matter of fact, it is known that a lower viscosity of a formulation allows for an easier drug diffusion through the vehicle than a higher viscosity and, consequently, a greater drug release [ 37 ]. Additionally, despite showing a greater viscosity than M1, after 24 h, M2 provided the release of a greater amount of AZT ( p < 0.05).…”

Polysaccharide-Based Transdermal Drug Delivery

“…Some polysaccharides with natural pharmacological activity are combined with NE to load drugs. The antifungal properties of CS were combined with the antifungal drug Fluconazole (FZ), essential oils, and sucrose fatty acid esters to prepare gel microemulsions for the treatment of mycoses [ 131 ]. CS emulsions loaded with 5-fluorouracil (5-FU) are considered a promising method for delivering 5-FU.…”