Nadifloxacin-Loaded Thermosensitive In Situ Gel Formulations with a Quality by Design Approach

In our study, we aimed to prepare topical in situ gels containing nadifloxacin (NDF), used in the treatment of acne and superficial skin infections, and to evaluate them using characterization studies.

Thermosensitive (temperature-sensitive) in situ gels were produced by the cold method using poloxamer 188 (P188) and poloxamer 407 (P407) after methylcellulose (MC) and gellan gum (GG) were dissolved. Finally, the NDF concentration in the gels was 1% (w/w). The prepared gels exhibited desirable properties, as shown by Fourier-transform infrared spectroscopy, and in clarity, pH, gelation temperature, gelling capacity, viscosity, mechanical properties (springiness, resilience, and cohesiveness), spreadability (work of adhesion, work of shear, stickiness, and firmness), drug content uniformity, in vitro release, and cytocompatibility (MTT cytotoxicity assay). The impact of critical materials in the formulation on the results was evaluated using quality by design.

The gelation temperatures of all NDF-included in situ gels were found to be in the range of 30-35.2 °C. Furthermore, the cytotoxicity of these gels was evaluated using MTT analysis. Based on the observed results, the most suitable gel was identified as N3, which contains 17.5% P407, 7% P188, 0.7% MC, 0.1% GG, and 1% NDF.

After further studies to determine its effectiveness against acne, it could become an alternative to existing creams for acne and superficial skin infections on the market.