Design and evaluation of amphotericin b and luliconazole nanoemulsions for targeted antifungal delivery

Background: Drugs like Amphotericin B and Luliconazole, which are poorly soluble in water and undergo significant first-pass metabolism, often show low bioavailability. Using nanoemulsion-based delivery systems can enhance absorption and efficacy in the treatment of fungal infections. This study aimed to develop and optimize nanoemulsion formulations of Amphotericin B and Luliconazole to improve their solubility and stability and to demonstrate potential for enhanced bioavailability. Methods: Preliminary characterization of Amphotericin B and Luliconazole included solubility analysis in various solvents, melting point determination, particle size, zeta potential, FTIR spectroscopy, DSC, and XRD. Amphotericin B was further evaluated using a validated RP-HPLC method and subjected to forced degradation studies. Pseudo-ternary phase diagrams were constructed to identify suitable Smix ratios for nanoemulsion formation. Formulations were prepared by homogenization and optimized using a central composite design. Key variables included globule size, zeta potential, homogenization speed, and time. Results and Discussion: The optimized Amphotericin B nanoemulsion (NE-02-8) exhibited a globule size of 168.2 nm, zeta potential of –28.9 mV, PDI of 0.578, drug content of 99.28%, and 99.48% transmittance. Statistical optimization using a Central Composite Design (CCD) confirmed that homogenization speed and time significantly influenced globule size (p < 0.05) and zeta potential (p < 0.05). In contrast, the Luliconazole nanoemulsion showed a globule size of 327.5 nm and a zeta potential of –27.9 mV. Conclusion: Nanoemulsion formulations of Amphotericin B and Luliconazole demonstrated enhanced solubility, stability, and physicochemical properties, indicating their potential to improve drug solubilization and stability relative to conventional formulations.