LAUSR

Chitosan microcapsules were synthesized by the method of ionic gelling. The oxolinic acid was encapsulated in chitosan microcapsules with different concentrations, which was corroborated by FT-IR bands of the capsules that are typical of chitosan and the antibiotic. The inclusion of the antibiotic in the microspheres,was determined by means of thermogravimetry since there were two decompositions temperatures corresponding to different compounds.At several concentrations of oxolinic acid chitosan microspheres had different external morphology, by means of SEM was observed that greater concentration of antibiotic exhibited a smoother external texture, being spherical most of them. The solubility of chitosan microspheres was very low in sea and nanopure water, since the protonationat basic pH of the amino group of chitosan is very low, the solubility was lower.The solubilities of chitosan with different concentrations of antibiotic micro-spheres showed a Gaussian tendency of solubility at different acid pH ranges (hydrogels). The optimum pH of solubility of chitosan spheres occured at pH 3.5, what it was observed at the maximum point of the curve.Chitosan microcapsules had different concentrations of oxolinic acid, because release of antibiotic concentration may occur and was measured by the HPLC method. The percentage of encapsulation of the microspheres was high, being all of them greater than 90%. The release of oxolinic acid on chitosan microspheres was faster at pH 5.7, since the release began from the time 1, instead at pH 7.5 was slower, since the release began after 3 times. Chitosan microcapsules had an average dry weight of 1.1 × 10-3 mg.