人乳头瘤病毒(HPV)感染的快速、特异的鉴定和灵敏的检测是预防宫颈癌的关键,特别是在资源有限的地区。在这项工作中,我们希望提出一种毛细管供电和CRISPR/Cas12a响应的DNA水凝胶距离传感器,用于即时护理(POC)DNA测试。利用DNA水凝胶的热可逆性和毛细管作用,新型DNA水凝胶距离传感器可以通过在毛细管末端加载超薄CRISPR/Cas12a响应的DNA交联水凝胶膜来快速简单地构建。靶DNA特异性重组酶聚合酶反应(RPA)扩增子激活Cas12a酶的反式切割活性,裂解水凝胶膜中的交联DNA,并导致水凝胶的渗透性增加。因此,与阴性样品相比,含有靶DNA的样品溶液以更长的距离进入毛细管。读取溶液在毛细管中的移动距离,新型传感器无需任何特殊设备即可实现目标DNA检测。受益于RPA的指数靶扩增和CRISPR/Cas12a的反式切割的多重周转反应,开发的传感器可以在30分钟内视觉和特异性地检测低至1aM的HPV16DNA。这些突出的特点,包括特殊的敏感性和特异性,简单便携的设计,温和的测量条件,快速周转时间,和用户友好的读出,使新型距离传感器成为POC诊断应用的有前途的选择。
The rapid and specific identification and sensitive detection of human papillomavirus (HPV) infection is critical for preventing cervical cancer, particularly in resource-limited regions. In this work, we hope to propose a capillarity-powered and CRISPR/Cas12a-responsive DNA hydrogel distance sensor for point-of-care (POC) DNA testing. Using the thermal reversibility of DNA hydrogel and capillarity, the novel DNA hydrogel distance sensor can be rapidly and simply constructed by loading an ultra-thin CRISPR/Cas12a-responsive DNA-crosslinked hydrogel film at the end of the capillary tube. The target DNA-specific recombinase polymerase reaction (RPA) amplicons activate the trans-cleavage activity of the Cas12a enzyme, cleaving the crosslinked DNA in hydrogel film, and causing an increase of hydrogel\'s permeability. As a result, a sample solution containing target DNA travels into the capillary tube at a longer distance compared to the negative samples. Reading the solution traveling distance in capillary tubes, the novel sensor realizes target DNA detection without any special equipment. Benefiting from the exponential target amplification of RPA and multiple turnover response of trans-cleavage of CRISPR/Cas12a, the developed sensor can visually and specifically detect as low as 1 aM HPV 16 DNA within 30 min. These outstanding features, including exceptional sensitivity and specificity, simple and portable design, mild measurement conditions, quick turnaround time, and user-friendly read-out, make the novel distance sensor a promising option for POC diagnostic applications.