中文摘要：

得到性能良好的SA/PU共混微球以用于药物缓控释;方法：利用预聚-扩链-中和-分散法合成阴离子型PU水溶液;将SA水溶液与PU水溶液按质量比为1∶1,1∶2,1∶3,1∶4,1∶5混合,用滴制法制备共混微球;测定了微球的凝胶化、圆整性及溶胀性能。结果表明：用TDI与PEG-6000和PEG-4000反应才能制备出PU水溶液,而只有水溶液才能和海藻酸钠水溶液混合完全得到理想的共混溶液;SA/PU共混微球28h后凝胶化完全,SA微球48h后可凝胶化完全。PEG-6000合成的PU与海藻酸钠共混得到的微球圆整性要好于PEG-4000合成的PU与海藻酸钠共混得到的微球。且随着复合微球中PU的含量增大,微球的圆整性变好;SA/PU复合微球在蒸馏水（pH7）和盐酸（pH1）中均不溶胀,在磷酸缓冲溶液（pH6.86）中快速溶胀,在4～5h后开始崩解。结论：SA/PU复合微球在胃液中保持原状,在肠液中溶胀,可作为药物的缓释载体。

英文摘要：

Objective： The study was aimed at obtaining favourable SA/PU complex hydrogel microspheres for drug controlled delivery System. Methods： First PU anionic solution was synthesized by prepolymer-chain-neutralization-dispersion. Subsequently SA solution and PU solution was completely mixed with different quality rate （1 ~ 1,1 ： 2,1 ： 3,1 ： 4, 1 ： 5）, which was trickled to shape complex microspheres. Finally, the nature including gelatinize, round and swelling of microspheres was determined. Results： PU solution, which could only be synthesized by TDI responded with PEG-6000 or PEG-4000, could be mingled with SA solution to form ideal solution. SA/PU microspheres were gelatinized completely in 28 hours and SA microspheres was 48 hours. The entire round of microspheres formed by composite solution of PU which was synthesis by PEG-6000 and SA was better than that of PEG-4000, and with content of PU in the complex micro spheres increased, roundness was improved. SA/PU microspheres didn＇t swell in distilled water （pH 7） and HC1 （pH 1）, but them swelled rapidly in phosphate buffer solution （pH 6.86） and disaggregated after 4-5 hours in phosphate. Conclusion： SA/PU composite microspheres in gastric juice doesn＇t changed, but swell in intestinal fluid, so them can be used as drug delivery carrier.