Development and Characterization of a Hydrogel Containing Chloramphenicol-Loaded Binary Ethosomes for Effective...

Acne is a serious disfiguring follicular sebaceous gland disorder that negatively affects patients' quality of life and self-image. Chloramphenicol (CAM) is effective against Propionibacterium acnes and Staphylococcus aureus which cause acne, often used as a hospital preparation for acne treatment. However, because of its toxicity and poor water solubility, its use has been restricted. To overcome these limitations, the study focused on developing CAM-loaded binary ethosomes (CAM-BE) and incorporating them into a hydrogel system for transdermal delivery.

CAM-BE were prepared and characterized. Following incorporation of the selected formulation into the hydrogel, the formulation's skin-interaction was evaluated using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and confocal laser scanning microscopy (CLSM). Furthermore, a rat ear acne model was used to evaluate the formulation's in vivo anti-inflammatory efficacy and ex vivo skin permeability.

The optimal formulation contained ethanol/propylene glycol ratios of 3:7 (w/w), exhibited particle size was 97.68 ± 4.9 nm, zeta-potential was -23.5 ± 1.3 mV, and encapsulation efficiency was 60.36 ± 2.12%. The BE hydrogel that was created showed persistent drug release. Additionally, it demonstrated an enhanced flow of 4.374 ± 0.12 μg/cm²/hour, permeability coefficient was 3.65 ± 0.09 cm/h×10^-3, and apparent skin deposition was 17.77 ± 1.13 μg/cm². CLSM and ATR-FTIR confirm that loading CAM into a binary ethosomes enables drugs to pass more easily through the stratum corneum. In vivo testing and histopathological analysis demonstrated that the CAM-BE hydrogel significantly inhibited swelling in the rat auricle, compared to both the free CAM hydrogel and adapalene hydrogel.

With their strong anti-inflammatory properties and improved skin penetration, binary ethosomes could be a viable new CAM delivery method. The new formulation was therefore seen as quite promising.