在血液中高效地捕获循环肿瘤细胞（CTCs）对于癌症的筛查、治疗和评估转移或复发的风险至关重要。目前将特定抗体（如EpCAM抗体）固定在材料表面上是高效捕获CTCs的主要方法。然而，抗体固定的策略通常有使用多种化学试剂和复杂预处理过程的缺点。在这里，我们开发了一种简单的EpCAM抗体固定策略，无需额外的化学试剂。通过利用光功能化二氧化钛（TiO2）的正电荷特性，通过静电作用固定EpCAM抗体的负电荷端，从而使抗体完全暴露出抗原结合位点。实验结果显示，光功能化TiO2表面具有明显的正电荷和超亲水性能，可以固定大量的EpCAM抗体并保持良好的活性。体外CTCs捕获实验表明，EpCAM抗体修饰的光功能化TiO2可以有效地捕获CTCs。兔体循环实验的结果表明，EpCAM抗体修饰的光功能化TiO2可以准确地从全身血液中捕获CTCs。预计基于光功能化TiO2的简单EpCAM抗体固定策略未来将在高效捕获CTCs方面发挥作用。版权所有© 2023 Deng, Liu, Chen, He, Lin, Liu, Chen和Liu。

The highly efficient capture of circulating tumor cells (CTCs) in the blood is essential for the screening, treatment, and assessment of the risk of metastasis or recurrence of cancer. Immobilizing specific antibodies, such as EpCAM antibodies, on the material's surface is currently the primary method for efficiently capturing CTCs. However, the strategies for immobilizing antibodies usually have the disadvantages of requiring multiple chemical reagents and a complex pre-treatment process. Herein we developed a simple strategy for the immobilization of EpCAM antibodies without additional chemical reagents. By utilizing the positive charge property of the photo-functionalized titanium dioxide (TiO2), the negatively charged carboxyl terminal of EpCAM antibodies was immobilized by electrostatic interaction, allowing the antibodies to expose the antigen binding site fully. The experimental results showed that the photo-functionalized TiO2 surface had a marked positive charge and super-hydrophilic properties that could immobilize large amounts of EpCAM antibodies and keep excellent activity. CTCs capture experiments in vitro showed that the EpCAM antibodies-modified photo-functionalized TiO2 could efficiently capture CTCs. The results of blood circulation experiments in rabbits showed that the EpCAM antibodies-modified photo-functionalized TiO2 could accurately capture CTCs from the whole body's blood. It was foreseen that the strategy of simple immobilization of EpCAM antibodies based on photo-functionalized TiO2 is expected to serve in the efficient capture of CTCs in the future.Copyright © 2023 Deng, Liu, Chen, He, Lin, Liu, Chen and Liu.