Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China; Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases, Yangzhou University, Yangzhou, PR China; Jiangsu Key Laboratory of Experimental & Translational Noncoding RNA Research, Medical College, Yangzhou University, Yangzhou, China.
Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China; Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases, Yangzhou University, Yangzhou, PR China; Jiangsu Key Laboratory of Experimental & Translational Noncoding RNA Research, Medical College, Yangzhou University, Yangzhou, China.
Biosens Bioelectron. 2022 Jun 1;205:114110. doi: 10.1016/j.bios.2022.114110. Epub 2022 Feb 22.
Circulating tumour DNAs (ctDNAs) have been reported to be associated with real-time information of progression; however, an accurate and sensitive method has not been established. Herein, a novel dual-signal amplification strategy based on a pump-free surface-enhanced Raman scattering (SERS) microfluidic chip and a catalytic hairpin assembly (CHA) technique was developed for the dynamic monitoring of BRAF V600E and KRAS G12V, which are two non-small cell lung cancer (NSCLC)-related ctDNAs. In the presence of targets, CHA reactions can be triggered between two hairpin DNAs, fixing Pd-Au core-shell nanorods (Pd-AuNRs) onto the magnetic beads (MBs) surface. Thereafter, the composite structures can assemble under the action of magnet, enabling dual-amplification of SERS signal. Using this strategy, the limit of detection (LOD) was low (i.e. at the aM level) in serum. Furthermore, the entire chip-based analysis process could be completed within 5 min, eliminating manual incubation and heavy-duty injection pumps. The selectivity, reproducibility and uniformity of the proposed pump-free SERS microfluidic chip were satisfactory. This superior analysis strategy was finally applied to quantify BRAF V600E and KRAS G12V in tumour-bearing nude mice serum, the results of which corresponded with those of real-time polymerase chain reaction. Overall, this study provides a promising alternative tool for the dynamic monitoring of ctDNA expression level which can benefit the clinical diagnosis of NSCLC.
循环肿瘤 DNA（ctDNA）已被报道与进展的实时信息相关；然而，尚未建立准确和敏感的方法。在此，开发了一种基于无泵表面增强拉曼散射（SERS）微流控芯片和催化发夹组装（CHA）技术的新型双重信号放大策略，用于动态监测与非小细胞肺癌（NSCLC）相关的两种 ctDNA，即 BRAF V600E 和 KRAS G12V。在存在靶标的情况下，CHA 反应可以在两条发夹 DNA 之间触发，将钯-金核壳纳米棒（Pd-AuNRs）固定在磁性珠（MBs）表面。此后，在磁铁的作用下，复合结构可以组装，从而实现 SERS 信号的双重放大。使用该策略，在血清中的检测限（LOD）较低（即在 aM 水平）。此外，整个基于芯片的分析过程可以在 5 分钟内完成，无需人工孵育和重型注射泵。所提出的无泵 SERS 微流控芯片具有令人满意的选择性、重现性和均匀性。最后，该优越的分析策略被应用于定量荷瘤裸鼠血清中的 BRAF V600E 和 KRAS G12V，其结果与实时聚合酶链反应的结果相对应。总体而言，本研究为动态监测 ctDNA 表达水平提供了一种有前途的替代工具，有助于 NSCLC 的临床诊断。
