Improvement of the Solubility Amphotericin B Using Olive Oil Nanoemulsion Coated with Chitosan for More Effective Treatment of Zoonotic Cutaneous Leishmaniasis

Amphotericin B (AMB) is a macrolide polyene antibiotic presenting potent anti-cutaneous leishmania activity. Nonetheless, its low water solubility, side effects, and toxicity have limited its therapeutic efficiency. The present study aimed to improve the solubility of AmB in oil-in-water using chitosan and determine its cytotoxicity on macrophages, as well as Leishmania major promastigote and amastigote. Olive oil, span 80, tween 80, AmB, and DMSO were employed as excipients, and nanoemulsions (NEs) were prepared by sonicator bath at 37 °C for 1 h at the highest power and stirred overnight with pH 5.5. Thereafter, chitosan was added to the NE and stirred overnight to obtain chitosan nanoemulsion (CNE). The CNE was optimized and investigated for different in-vitro parameters, such as droplet size, zeta potential, morphology, drug content, in-vitro drug release, and in-vitro cytotoxicity. Droplet size and zeta potential for CNE with AmB were obtained at 13.33 ± 1.3 nm, 30.90 ± 1.9 mV, respectively. Encapsulation efficiency and drug loading of the final CNE were reported as 100% and 0.64%, respectively. The results of in-vitro cytotoxicity revealed that CNE did not cause any cytotoxicity in macrophages. The CNE not only reduced drug toxicity for the macrophage but also had a suitable inhibition effect on the parasite. The CNE with AmB exerted an inhibitory effect on L. major promastigote/ amastigote phase. Furthermore, CNE with AmB represented a promising approach for leishmaniasis treatment. Therefore, the obtained outcomes of the IC(50) proposed that the application of CNE can cause no toxicity and guarantees better quality drug release.