Li Yang, Zhang Qianqian, Sun Zhen, Rong Mingjie, Jiang Chunhuan, Lu Lehui
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China.
ACS Nano. 2024 Apr 2;18(13):9645-9655. doi: 10.1021/acsnano.4c00952. Epub 2024 Mar 19.
The utilization of alkyl radicals (•R) for hypoxic tumor therapy has great prospects due to its O-independence and high reactivity. However, correlational initiators for activation remain scarce. Here, we report that ultrasound excitation of oleic acid-capped BaTiO (OA@BaTiO) can result in an •R cascade and hence a means to conquer hypoxic tumors. Mechanistic studies find that the •R signal disappears when OA@BaTiO undergoes acid washing post-treatment, which is a common procedure for removing the unwanted byproduct BaCO. Combined with the infrared spectrum analysis, acid treatment was proven to weaken the peaks at 2840-2970 cm characteristic of -CH- and terminal -CH stretching vibration of OA. There is compelling evidence that high temperature thermal oxidation of OA involves the generation of •R. Thus, acid washing is considered to remove the loosely bound yet catalytically active OA. And piezoelectric BaTiO, a potential electron-hole redox catalyst, can sensitize these OA molecules and disintegrate them to •R. This unexpected discovery provides us with a distinctive mentality to seek diverse •R initiators for tumor ablation, as well as an additional perspective on the postprocessing of synthetic materials.
由于烷基自由基（•R）不依赖氧气且具有高反应活性，其在缺氧肿瘤治疗中的应用前景广阔。然而，用于激活的相关引发剂仍然稀缺。在此，我们报道油酸包覆的钛酸钡（OA@BaTiO）经超声激发可导致•R级联反应，从而成为一种攻克缺氧肿瘤的方法。机理研究发现，当OA@BaTiO经过酸洗后处理（这是去除不需要的副产物碳酸钡的常用步骤）时，•R信号消失。结合红外光谱分析，证明酸处理会减弱OA中-CH-和末端-CH伸缩振动特征的2840 - 2970 cm处的峰。有确凿证据表明OA的高温热氧化涉及•R的产生。因此，酸洗被认为是去除了松散结合但具有催化活性的OA。而压电材料钛酸钡作为一种潜在的电子-空穴氧化还原催化剂，可以使这些OA分子敏化并将它们分解为•R。这一意外发现为我们寻找用于肿瘤消融的多种•R引发剂提供了独特思路，也为合成材料的后处理提供了新的视角。
