On-demand relief of local pain would allow patients to control the timing, intensity and duration of nerve block in a safe and non-invasive manner. Ultrasound would be a suitable trigger for such a system, as it is in common clinical use and can penetrate deeply into the body. Here, we demonstrate that ultrasound-triggered delivery of an anaesthetic from liposomes allows the timing, intensity and duration of nerve block to be controlled by ultrasound parameters. On insonation, the encapsulated sonosensitizer protoporphyrin IX produces reactive oxygen species that react with the liposomal membrane, leading to the release of the potent local anaesthetic tetrodotoxin. We also show repeatable ultrasound-triggered nerve blocks in vivo, with nerve-block duration depending on the extent and intensity of insonation. We did not detect any systemic toxicity, and tissue reaction was benign in all groups. On-demand, personalized local anaesthesia could be beneficial for the managing of relatively localized pain states, and potentially minimize opioid use.

中文翻译：

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超声波引发的局部麻醉。


按需缓解局部疼痛将使患者能够以安全、非侵入性的方式控制神经阻滞的时间、强度和持续时间。超声波是这种系统的合适触发因素，因为它在临床上很常见，并且可以深入人体。在这里，我们证明超声触发脂质体麻醉剂的输送可以通过超声参数控制神经阻滞的时间、强度和持续时间。在声波作用下，封装的声敏剂原卟啉 IX 产生活性氧，与脂质体膜发生反应，导致强效局部麻醉剂河豚毒素的释放。我们还展示了体内可重复的超声触发神经阻滞，神经阻滞持续时间取决于声波的范围和强度。我们没有检测到任何全身毒性，所有组的组织反应都是良性的。按需、个性化的局部麻醉可能有利于管理相对局部的疼痛状态，并有可能最大限度地减少阿片类药物的使用。