生物活性物质(尤其是药物)控制释放系统的研究,早在七十年代初就已在国外开展。曾将药物分散到一些具有生物降解活性的聚合物基质(如聚乳)酸中进行试验。到1980年前后,开始把可生物降解的聚α-谷氨酸(PAG)与甾体药物通过化学键合研制长效缓释系统。该系统不但能缓慢恒定地释放药物(基本上为零级释放),同时在释药以后不会在体内残留聚合物,因而副作用小,使用方便,肌注或埋植一次即可有长 Studies on the controlled release system of bioactive substances (especially drugs) have been carried out in foreign countries since the early 1970s. The drug has been dispersed in a number of biodegradable polymer matrix (such as polylactic acid) to test. By 1980, biodegradable poly-α-glutamic acid (PAG) and steroid drugs began to be chemically bonded to long-acting sustained release system. The system not only releases the drug slowly and consistently (essentially zero-order release), but also does not remain in the body after drug release, thus resulting in less side effects, ease of use, and intramuscular or implants