Preparation and characteristics of diatrizoate meglumine-loaded chitosan microspheres

The purpose of the present study is to prepare a diatrizoate meglumine-loaded chitosan microsphere, which could be used to be investigated by ultrasonic imaging technique in vivo and would has water absorption swelling property to dredge the obstruction. Diatrizoate meglumine-loaded chitosan microspheres were prepared by crosslink emulsification process, to use chitosan acetic acid solution as aqueous phase, liquid paraffin as oil phase, Span80 and n-butyl alcohol as surfactant, glutaraldehyde solution as crosslink agent. The effect of ratio of diatrizoate meglumine (ratio of W), the ratio of aqueous to organic phase (W/O ratio), the ratio of Span80 to liquid paraffin and the time of crosslink process were optimized by the single factor experiment and response surface experiment. And the optimum prepared microspheres´ appearance, distribution, diameter, zeta potential, thermal performance and release properties were measured and their swelling and development properties were observed. The diatrizoate meglumine-loaded chitosan microspheres had a good shape and uniform distribution by light microscope and transmission electron microscope, with average diameters of 1.53 μm and average zeta potential of -19.7 mV; the microspheres had a good sustained release property. And the swelling property of the diatrizoate megiumine-loaded chitosan microspheres varied in different conditions and developed clearly under the ultrasonic imaging technique. This study prepares a kind of diatrizoate meglumine-loaded chitosan microspheres, who can make the microspheres, develop and dredge the obstruction at the same time.