Using radiotherapy to activate chemotherapeutic conversion is a promising approach to reduce off-target toxicity in cancer therapy. Current radiation chemistry mostly relies on substrate to react with the primary species of water radiolysis, with the most abundant being hydrated electron (e−aq) and ·OH. However, only 280 nM e−aq is generated by 1 Gy radiation, fundamentally limiting the yield of conventional radiation chemistry. Here, we show a radiation-mediated catalyst significantly boosts the radiochemical conversion of caged compounds. Palladium precatalyst could be transformed to active Pd(0) by γ-ray of as low as 1 Gy. The radiochemical yield can reach 2750 nM/Gy, which is 10 times that of e−aq. The strategy works even when obstructed by 15 cm of animal tissue. We demonstrate its functionality within live cells, showcasing the synergistic radiation-directed chemotherapy. We anticipate the altered mechanism of action to be a starting point for using bio-compatible dose of ionizing radiation to chemically manipulate deep tissue.

中文翻译：

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放射治疗介导的催化前药治疗，具有比水合电子更高的放射化学转化率

使用放疗激活化疗转化是减少癌症治疗中脱靶毒性的一种有前途的方法。目前的辐射化学主要依靠底物与水辐射分解的主要物质发生反应，其中最丰富的是水合电子（e−aq）和·OH。然而，1 Gy 辐射仅产生 280 nM e−aq，从根本上限制了传统辐射化学的产量。在这里，我们展示了辐射介导的催化剂显着促进了笼状化合物的放射化学转化。钯预催化剂可以通过低至1 Gy的γ射线将其转化为活性Pd(0)。放射化学产率可达2750 nM/Gy，是e−aq的10倍。即使被 15 厘米的动物组织阻挡，该策略也能发挥作用。我们展示了它在活细胞内的功能，展示了协同放射定向化疗。我们预计改变的作用机制将成为使用生物相容剂量的电离辐射对深层组织进行化学操作的起点。