chitosan and plga microspheres as drug delivery ... - UniCA Eprints

4. RFP Loaded Chitosan Microspheres Prepared by Precipitation Method4.1.7. Statistical AnalysesAll experiments were repeated at least three times. Results are expressed as means ± standarddeviation. A difference between means was considered significant if the “p” value was lessthan or equal to 0.05.4.2. Result and Discussion4.2.1. Preparation of RFP-Loaded Chitosan MicrospheresThe primary goal of this study was to prepare microsphere formulations that could be used totarget the delivery of effective doses of RFP to macrophages after aerosol therapy.Precipitation and precipitation chemical-cross-linking methods are rapid and simpletechniques for producing RFP-loaded microspheres with small size and good reproducibilityfrom batch to batch. This production process is based on the solubility behaviour of chitosan,which is poorly soluble in water. Addition of an acid improves its solubility as a result ofprotonation of amino groups. Chitosan solubility is also affected by other anions present inthe solution. In the presence of phosphate, polyphosphate and sulphate ions, chitosan shows adecreased solubility. For this reason, sodium sulphate was chosen for microsphereformulations, since sulphate leads to a poorly soluble chitosan derivative, wherebymicrosphere formulation become possible.Composition of RFP-loaded chitosan microspheres is reported in table 4.1.Table 4.1: Chitosan Microspheres CompositionRFPCTSSodium Sulphate(20% w/w)AceticAcidGA 25%(w/w)Form.Ø 2mg/ml 0.20% 0.16 ml 2% -Form.1 2mg/ml 0.25% 0.2 ml 2% -Form.2 2mg/ml 0.50% 0.4 ml 2% -Form.3 2mg/ml 0.75% 0.6 ml 2% -Form.Ø G 2mg/ml 0.20% 0.16 ml 2% +Form.4 2mg/ml 0.25% 0.2 ml 2% +Form.5 2mg/ml 0.50% 0.4 ml 2% +Form.6 2mg/ml 0.75% 0.6 ml 2% +59