Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, P. R. China.
Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases, Yangzhou University, Yangzhou, 225001, P. R. China.
J Mater Chem B. 2022 Aug 17;10(32):6194-6206. doi: 10.1039/d2tb01024k.
Circulating tumor DNA (ctDNA) is an ideal biomarker for cancer diagnosis based on liquid biopsy, so there is an urgent need for developing an efficient, rapid, and ultrasensitive detection method to meet clinical needs. In this paper, a novel surface-enhanced Raman scattering (SERS) microfluidic chip combined with a catalytic hairpin assembly (CHA) was proposed to detect two non-small cell lung cancer (NSCLC)-related ctDNA (TP53 and PIK3CA-Q546K) simultaneously. The chip consists of six channels for parallel detection. In the reaction region, the CHA reaction between HP of the SERS probe and HP of the capture substrate was triggered by ctDNAs to form HP-HP duplexes. As the reaction proceeds, more and more SERS probes are captured on the substrate. The gathered reaction products continuously form a lot of hot spots, which greatly enhance the SERS signal. This reaction was completed within 5 minutes. Through this method, the detection limits of TP53 and PIK3CA-Q546K in human serum were as low as 2.26 aM and 2.34 aM, respectively. The microfluidic chip also exhibited high specificity, reproducibility and stability. The clinical feasibility of the SERS microfluidic chip was verified by analyzing the serum samples of healthy subjects and NSCLC patients. The reliability of the experimental results was verified by the qRT-PCR test. The constructed SERS-based analytical micro-platform has great potential in dynamic monitoring of cancer staging and could be used as a clinical tool for early cancer screening.
循环肿瘤 DNA（ctDNA）是液体活检中癌症诊断的理想生物标志物，因此迫切需要开发一种高效、快速和超灵敏的检测方法来满足临床需求。本文提出了一种新型的基于表面增强拉曼散射（SERS）的微流控芯片，结合催化发夹组装（CHA）技术，用于同时检测两种非小细胞肺癌（NSCLC）相关的 ctDNA（TP53 和 PIK3CA-Q546K）。该芯片由六个通道组成，用于并行检测。在反应区，SERS 探针的 HP 与捕获底物的 HP 之间的 CHA 反应被 ctDNA 触发，形成 HP-HP 双链体。随着反应的进行，越来越多的 SERS 探针被捕获到基底上。聚集的反应产物不断形成大量热点，大大增强了 SERS 信号。整个反应在 5 分钟内完成。通过这种方法，TP53 和 PIK3CA-Q546K 在人血清中的检测限分别低至 2.26 aM 和 2.34 aM。该微流控芯片还表现出高特异性、重现性和稳定性。通过分析健康受试者和 NSCLC 患者的血清样本验证了 SERS 微流控芯片的临床可行性。通过 qRT-PCR 测试验证了实验结果的可靠性。所构建的基于 SERS 的分析微平台在癌症分期的动态监测中具有巨大的潜力，可作为癌症早期筛查的临床工具。
