基于酶循环放大表面增强拉曼检测人乳腺癌细胞及细胞表面活性物质

Human breast cancer is a leading cause of death for women throughout the world and the critical issue for cancer diagnosis is to develop new diagnostic methods allowing one to detect the disease in an early stage. Nowadays, surface-enhanced Raman scattering (SERS) has become a powerful spectroscopy technique because of the high sensitivity, sharp "fingerprint" signals and simplicity, it is under active investigation in biological detection. In this project, a series of novel methods will be developed for detecting human breast cancer cell and the markers expressed on the surface of cancer cell based on SERS. Aptamers are single-stranded DNA or RNA oligonucleotides obtained through SELEX. Because the interaction between aptamer and its target is stronger than that between the aptamer and its complementary oligonucleotide, replacement of the complementary oligonucleotide by the target cell is facile, which leads to the transduction of aptamer-cancer cell interaction into DNA-based signal amplification assay. Based on the interaction of cancer cell and its aptamer, a series of detection method for human breast cancer cell will be developed in this project incorporating with enzyme-based cycle amplification techniques. The different markers expressed on the surface of the cancer cell will be detected using multiple Raman probes. The proposed methods may offer new approaches for sensitive and selective biomolecule analysis for early cancer diagnosis.

本项目拟开展人乳腺癌细胞及细胞表面活性物质的表面增强拉曼光谱检测及成像分析研究。通过合成新型的、具有较高生物相容性的表面增强拉曼基底及探针，提高拉曼检测的稳定性和灵敏度。将构建的拉曼基底和探针用于人乳腺癌细胞的检测，结合核酸适体识别技术及工具酶循环放大技术，将癌细胞的检测转变为DNA的信号放大检测。通过引入多种探针及原位放大技术，实现人乳腺癌细胞表面多种活性物质的表面增强拉曼检测及成像分析。为拉曼光谱在生物学及临床医学等领域的应用提供重要的参考和依据，也为癌症等重大疾病的早期准确诊断提供新方法、新技术。

本项目开展了人乳腺癌细胞及细胞表面活性物质的表面增强拉曼光谱检测及成像分析研究。通过制备新型的、具有较高生物相容性的表面增强拉曼基底及探针，提高了拉曼检测的稳定性和灵敏度。设计了新型的纳米探针，并利用探针自组装成具有支链结构的DNA-金纳米球，该纳米球表面结合有大量标记拉曼活性分子的单链DNA，作为拉曼检测的新型探针。进一步将构建的拉曼基底和新型探针用于细胞检测，以人乳腺癌细胞（MCF-7）为靶向细胞，利用核酸适体的特异性识别作用，实现了MCF-7细胞表面两种活性物质的同时检测，并对其分布情况进行了拉曼成像分析。此外，结合工具酶循环放大技术，实现了DNA甲基化酶及DNA单碱基突变的检测，拓展了表面增强拉曼检测的使用范围。. 总之，本项目圆满完成了人乳腺癌细胞及细胞表面活性物质的表面增强拉曼光谱检测及成像分析研究，为拉曼光谱在生物学及临床医学等领域的应用提供了重要的参考和依据，也为进一步开展新的课题研究打下了坚实的基础。