Abstract：
In numerous malignancies, miRNA-155 is overexpressed and has oncogenic activity because it is one of the most efficient microRNAs for inhibiting apoptosis in human cancer cells. As a result, the highest sensitive detection of the miRNA-155 gene is a technological instrument that can enable early cancer screening. In this study, a miRNA-155 biosensor was created to create a hairpin probe that can bind to the miRNA-155 gene using lambda nucleic acid exonuclease, which can cut the 5\' phosphorylated double strand, and by the DNA probe is recognized by the Cas12a enzyme, which then activates Cas12a to catalyze trans-cutting produces strong fluorescence. Research finding, the target concentration\'s logarithm and corresponding fluorescence intensity have a strong linear connection, and the limit of detection (LOD) of the sensing system was determined to be 8.3 pM. In addition, the biosensor displayed exceptional specificity, low false-positive signal, and high sensitivity in detecting the miRNA-155 gene in serum samples. This study\'s creation of a biosensor that has high sensitivity, good selectivity, and is simple to operate provides promising opportunities for research into biosensor design and early cancer detection.
摘要：
在许多恶性肿瘤中，miRNA-155过表达并具有致癌活性,因为它是抑制人癌细胞凋亡的最有效的microRNA之一。因此,miRNA-155基因的最高灵敏度检测是一种能够进行早期癌症筛查的技术工具。在这项研究中,一个miRNA-155生物传感器被创建创建一个发夹探针，可以结合miRNA-155基因使用λ核酸外切酶，可以切割5个磷酸化双链，DNA探针被Cas12a酶识别，然后激活Cas12a催化反式切割产生强烈的荧光。研究发现，目标浓度的对数和相应的荧光强度有很强的线性关系，并且该传感系统的检测限(LOD)被确定为8.3pM。此外,生物传感器表现出非凡的特异性，低假阳性信号，血清样品中miRNA-155基因检测灵敏度高。这项研究创造了一种高灵敏度的生物传感器，良好的选择性，并且操作简单，为生物传感器设计和早期癌症检测的研究提供了有希望的机会。
