Formulation and Evaluation of Fluconazole Containing Sodium Alginate/Methylcellulose-Based Buccal Films for Potential Treatment of Oral Candidiasis

Background/Objectives: Oral candidiasis is an infection of the oral cavity caused by Candida albicans. Mucoadhesive buccal films could adhere to the buccal mucosa for prolonged periods, improving the therapeutic outcomes of patients with oral candidiasis. This study aimed to develop and evaluate the properties of fluconazole containing sodium alginate/methylcellulose-based buccal films for potential treatment of oral candidiasis. Methods: Drug-polymer compatibility was investigated using FT-IR spectrophotometry. Three optimised fluconazole films (F1 to F3) containing 1–1.6% sodium alginate and methylcellulose (1.6%) were formulated using the solvent-casting method. Their physicomechanical properties were characterised using standard protocols. Drug content and in vitro drug release profiles were evaluated using UV-visible spectroscopy; in vitro/ex vivo mucoadhesion studies were conducted using the shaking water bath technique, and their antifungal activity against Candida albicans was evaluated using the agar ditch method. Results: FT-IR data analysis revealed that sodium alginate, methylcellulose and fluconazole were compatible in the films. The films were off-white, smooth, peelable, thin, with satisfactory pH values, folding endurance, drug content, excellent zones of inhibition against Candida albicans (40 mm), controlled drug release profile (3.6–4.1 mg/cm2 after 6 h), and they displayed Korsmeyer–Peppas drug release kinetics. Film F3 containing 1.6% sodium alginate and 1.6% of methylcellulose exhibited superior swelling index (70 ± 1%), tensile strength (0.68 ± 0.04 MPa) and in vitro/ex vivo mucoadhesion time (5.5 ± 0.3 h; 2.3 ± 0.3 h) relative to other studied films. Conclusions: The sodium alginate content of the films influenced their tensile and mucoadhesive properties. Film F3 was the most promising formulation for potential treatment of oral candidiasis.