Background: In recent years, a growing concern about resistance to anti-infective agents has emerged. One of the most common microbial agents is Candida albicans. Under certain conditions, C. albicans can cause infections of skin and mucosal tissues. Nystatin (Nys) is a broad spectrum antifungal, which is indicated for the treatment of mucosal infections caused by Candida ssp such as patients under radiological treatment. Nys is a photosensitive drug and very poorly soluble in aqueous media. Therefore, microencapsulation can be the solution for its limiting factors^1-2.

Purpose: The aim of this work was to design, develop and characterize two types of microparticles as appropriate nystatin delivery systems for topical use: alginate microparticles (AM) and chitosan coated alginate microparticles (CCM).

Methods: The formulation of the microparticles was based on the emulsification/internal gelation methodology with modification³. First, a W/O emulsion was elaborated. Sodium alginate aqueous solution, CaCo₃ and Nys were the ingredients of the internal phase, and vegetable oil the external phase⁴. The resulting microparticles were characterized in terms of particle size, percentage yield (PY), loading capacity (LD), encapsulation efficiency (EE) and mucoadhesion ability.

Results and Discussion: Microparticles ranged from 51.21 µm for AM to 57.20 µm for CCM. The PY values were 83.26% and for 79.67% AM and CCM, respectively. The LD values for the inside/surface were 6.78%/0.40% for AM and 4.87%/0.91% for CCM. The values of EE for inside and surface were 81.12%/12.07% for AM and 85.08%/9.19% for CCM. CCM was the system that exhibited the best mucoadhesive properties.

Conclusions: The ability of these systems to adhere mucous membranes has great appeal for the treatment of localized infections. Thus these microparticulate systems could be proposed as a suitable vehicle for this kind of mucosal infections being an alternative therapy.