基于功能DNA纳米技术的LSAW生物传感器技术的建立及在地中海贫血基因检测中的应用研究

单核苷酸多态性（SNP）、单核苷酸变异（SNV）和拷贝数目变异（CNV）等标志物已被用于诊断地中海贫血等多种疾病。目前检测SNP、SNV和CNV的荧光定量PCR、DNA测序、基因芯片等技术，需扩增及标记，有假阳性且重复性差。漏声表面波（LSAW）生物传感器灵敏度高、无需标记，优于上述技术。由于外周血中SNP、SNV及CNV含量极低，因此实现它们的无扩增检测是生物传感器领域的攻关难点。基于前期研究，我们认为LSAW生物传感器灵敏性若能进一步提高，将最有希望突破该技术难关。本项目拟构建聚丙烯酰胺修饰功能DNA纳米探针，从增加LSAW传感器表面质量负载和溶液黏度两方面提高传感器敏感性。同时为保证检测体系的稳定性，我们拟设计新型倒插式LSAW芯片及微容量检测体系。最终建立一种适用于SNP、SNV和CNV无扩增同时检测的新型倒插式LSAW生物传感器技术，并探讨该技术在地中海贫血基因检测中的应用价值。

Single nucleotide polymorphism (SNP), single nucleotide variation (SNV) and copy number variation (CNV) have been used to diagnose diseases such as thalassanemia. Now Real-time-PCR, DNA sequencing and gene array have been used to detect nucleotide markers such as SNP, SNV and CNV. However, these techniques require nucleotide amplification and labeling, which may lead to higher false positive rate and lower repeatability. Leaky surface acoustic wave (LSAW) biosensors have higher sensitivity and donot require labeling, thus outweigh the above techniques. Since the concentration of SNP, SNV and CNV are very tiny in the peripheral blood, detection of these biomarkers without nucleotide amplification is the technology challenge in the field of biosensors. Based on the former research, we believe that the LSAW biosensors would be the promise to rise this technology challenge, if the sensitivity of the biosensors could be improved. In this proposal, we intend to design Polyacrylamide modified functional DNA nano-probes to develop the sensitivity of the LSAW biosensors through increasing both mass load and the liquid viscosity on the surface of the biosensors. At the same time, in order to ensure the stability of this biosensors, we plan to design a new insert type LSAW chip and corresponding micro-capacity detection system. Eventually, a new insert type LSAW biosensor technique will be developed for SNP, SNV and CNV detection. Further, the application value of this new technique in genetic detection of thalassanemia will be studied.