Investigation On The Polyvinyl Alcohol/Chitosan Microspheres As Medical Delivery Materials

As a single basic polysaccharide in nature, chitosan (CS) is widely used inmedicine as medical delivery materials with its non-toxic, biodegradable andbiocompatible characteristics. When the chitosan is used as drug delivery carrier, ithas many excellent properties, such as prolonging the action time, reducing sideeffects of drugs, changing the route of administration, and enhancing the stability ofthe drug itself and the permeability of cell membrane. However, a large number ofexperiments confirmed that, if the use of pure chitosan as medicinal auxiliarymaterials in drug release, the efficiency and cost is not satisfactory, chitosan need tobe modified.In order to improve the slow release performance and reduce the cost of CS, weblend the CS with PVA and prepared the microspheres of PVA/CS, and researchedthe effect of preparation on the property of microspheres, therefore we determinedthe optimum conditions.The dosage of emulsifier, crosslinker and dosing ratio were chose as majorfactors, we researched the effect of the factors on PVA/CS/LVFX, especially onpattern, drug loading efficiency and slow-release effect. The Results showed thatthe best synthesis process include: quality ratio of levofloxacin hydrochloride andchitosan is1:2, glutaraldehyde dosage is2.0mL, PVA dosage is5%of chitosan,amount of emulsifier is2mL. The drug loading rate can reach12.8%. The cross-linking degree test, scanning electron microscopy (SEM) and Fourier transforminfrared spectrometer (FT-IR) were tested to indicate the structure and properties ofthe composite microspheres. The experimental results showed that the crosslinkingdegree of chitosan has been achieved up to81.6%.Drug release test results showedthat levofloxacin hydrochloride in PVA/CS/LVFX microspheres, basic releasedcompletely within6h.Then the levofloxacinhydrochloride in the CS/LVFXmicrospheres basically release completely in6h. It shows that, the microspheres of PVA/CS/LVFX are much better than CS/LVFX in drugloading rate, entrapment rateand slow release performance.