ABSTRACT
Objective: Solid lipid nanoparticles (SLNs) are at the forefront of the rapidly developing field of nanotechnology with several potential applications in drug delivery and research. The aim of this study was to develop and characterize SLNs formulae of Terbinafine HCl (TFH) for topical drug delivery applications. Methods: SLNs were prepared using the solvent injection technique. Glyceryl Monostearate (GMS) served as the lipid base. Three stabilizers; Tween 80, Cremophor RH40, and Poloxamer 188, were used. The effect of stabilizer type and concentration, as well as the lipid concentration, were studied, factorial design of 32*21was applied. The prepared SLNs were characterized regarding their particle size, zeta potential, polydispersity index (PDI), entrapment efficiency percent (EE %), and physicochemical stability. The selected formulae were subjected to further investigations such as morphological studies, in vitro release studies, and Infrared (IR) spectroscopy. They were compared with the marketed cream Lamifen® in term of their antifungal activity against Candida albicans. Results: Lipid concentration, together with the type and concentration of stabilizer, appeared to be the main cornerstones which affect the formation of SLNs. Smaller particle size was observed when increasing the stabilizer concentration and decreasing the lipid concentration. Higher EE% was observed when increasing both the stabilizer and the lipid concentrations. Formulae (F6, F12 andF19) were selected as the most suitable SLNs with optimum particle size of 480.2±18.89, 458.6±12.45 and 246.7±10.5 nm, respectively as well as the highest EE% of 87.13±0.19, 93.69±0.7 and 95.06±0.25, respectively. In vitro microbiological screening of their antifungal activity showed significantly larger zones of inhibition of diameters 25.9±0.25, 25±0.35 and 24.67±0.36 mm, respectively in comparison with the marketed Lamifen® cream which showed a zone of 11.2±0.44 mm diameter. Conclusion: Applying SLNs containing TFH as topical antifungal preparations may be considered as a very promising option as they show good physicochemical characterization with high antifungal activity, which delineates them as a promising dosage form for topical antifungal treatment.
ABSTRACT
Objective: Bemotrizinol (BEMT) is the most efficient broad-spectrum UV-absorber having a dual mechanism of action in absorbing and reflecting photons. The main objective of this work was to develop successful oil in water (o/w) nanoemulsion for improving the solubility of BEMT and its protective characteristics. Methods: Pseudo-ternary phase diagrams were constructed using labrafac PG and isopropyl myristate as oil phase, tween 80 as surfactant (S) and cremophor EL as cosurfactant (CoS) the ratio of S/CoS was determined according to highest percent of water incorporation to the system. Full factorial study design (24) using Design-Expert® software was adopted to study the effect of four independent variables namely: oil type, oil concentration, S/CoSmix (3:1) concentrations and BEMT concentration on the particle size and the in vitro release at 2 h (Q2h) of the prepared nanoemulsion formulae. Two systems each of eight formulae were developed and evaluated through droplet size analysis, zeta potential measurement, refractive index, in vitro drug release and according to the desirability value two formulae (F6 and F14) were used for further evaluations including in vitro sun protection factor (SPF), ex-vivo deposition by tape stripping technique, permeation test and photostability study. Results: Formula (F14) was chosen as the optimum formula having an in vitro SPF of 16.08±0.39, lowest permeation of 140±0.06 μg/cm2after six h and highest photostability (t90% = 168.02) after 120 min. Conclusion: Despite the poor solubility of bemotrizinol, it could be enhanced by novel drug delivery systems with good SPF value while maintaining its photostability.