Preparation of ciprofloxacin-encapsulated poly-ε- caprolactone microcapsules by the solvent evaporation technique

The objective of this study was to prepare ciprofloxacin (CIP) encapsulated poly-e-caprolactone (PCL) microcapsules by the single emulsion oil- in-water (o/w) solvent evaporation method. The obtained microcapsules were characterized for size, morphology, drug loading and entrapment efficiency. The physical state of microcapsules was determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). Storage stability, the in vitro drug release and mathematical modeling of drug release were also tested. It was found that obtained microcapsules had spherical shape and their size range was from 57.5 µm to 234.7 µm. The drug loading of microcapsules was from 1.72% to 11.02%. The optimal conditions of the encapsulation process include the drug/polymer ratio 2/1, using homogenizer for 5 min at 15000 rpm to disperse CIP in PCL solution and aqueous phase at pH 5.5. The results of CIP release study indicate that obtained microcapsules might be successfully used for designing sustained release dosage forms.