Extended-release local anesthetics (LAs) have drawn increasing attention with their promising role in improving analgesia and reducing adverse events of LAs. Nano-structured carriers such as liposomes and polymersomes optimally meet the demands of/for extended-release, and have been utilized in drug delivery over decades and showed satisfactory results with extended-release. Based on mature technology of liposomes, EXPAREL, the first approved liposomal LA loaded with bupivacaine, has seen its success in an extended-release form. At the same time, polymersomes has advances over liposomes with complementary profiles, which inspires the emergence of hybrid carriers. This article summarized the recent research successes on nano-structured extended-release LAs, of which liposomal and polymeric are mainstream systems. Furthermore, with continual optimization, drug delivery systems carry properties beyond simple transportation, such as specificity and responsiveness. In the near future, we may achieve targeted delivery and controlled-release properties to satisfy various analgesic requirements.

中文翻译：

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纳米结构延长释放局麻药的研究进展。

缓释局部麻醉剂（LAs）在改善镇痛和减少LAs不良反应方面具有前途作用，因此受到越来越多的关注。纳米结构的载体，例如脂质体和聚合物体，可以最佳地满足缓释的要求，并已用于药物递送数十年，并在缓释方面显示出令人满意的结果。基于脂质体的成熟技术，EXPAREL是首个获批准的载有布比卡因的脂质体LA，已经以缓释形式获得了成功。同时，聚合物脂质体比具有互补特征的脂质体具有进步，这激发了杂合载体的出现。本文总结了纳米结构缓释LA的最新研究成果，其中脂质体和聚合物是主流系统。此外，通过不断的优化，药物输送系统具有超越简单运输的特性，例如特异性和响应性。在不久的将来，我们可能会实现有针对性的递送和控释特性，以满足各种止痛要求。