Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350004, China.
Biosens Bioelectron. 2011 Feb 15;26(6):2870-6. doi: 10.1016/j.bios.2010.11.030. Epub 2010 Dec 1.
In this study, a novel DNA electrochemical probe (locked nucleic acid, LNA) was designed and involved in constructing an electrochemical DNA biosensor for detection of promyelocytic leukemia/retinoic acid receptor alpha (PML/RARα) fusion gene in acute promyelocytic leukemia for the first time. This biosensor was based on a 'sandwich' sensing mode, which involved a pair of LNA probes (capture probe immobilized at electrode surface and biotinyl reporter probe as an affinity tag for streptavidin-horseradish peroxidase (streptavidin-HRP). Since biotin can be connected with streptavidin-HRP, this biosensor offered an enzymatically amplified electrochemical current signal for the detection of target DNA. In the simple hybridization system, DNA fragment with its complementary DNA fragment was evidenced by amperometric detection, with a detection limit of 74 fM and a linear response range of 0.1-10 pM for synthetic PML/RARα fusion gene in acute promyelocytic leukemia (APL). Otherwise, the biosensor showed an excellent specificity to distinguish the complementary sequence and different mismatch sequences. The new pattern also exhibited high sensitivity and selectivity in mixed hybridization system.
在这项研究中，设计了一种新型 DNA 电化学探针（锁核酸，LNA），并首次将其用于构建用于检测急性早幼粒细胞白血病中早幼粒细胞白血病/维甲酸受体α（PML/RARα）融合基因的电化学 DNA 生物传感器。该生物传感器基于“三明治”传感模式，涉及一对 LNA 探针（固定在电极表面的捕获探针和生物素化报告探针作为链霉亲和素-辣根过氧化物酶（streptavidin-HRP）的亲和标签）。由于生物素可以与链霉亲和素-HRP 连接，因此该生物传感器提供了酶放大的电化学电流信号，用于检测靶 DNA。在简单的杂交体系中，通过电流检测证明了具有互补 DNA 片段的 DNA 片段，对于急性早幼粒细胞白血病（APL）中的合成 PML/RARα 融合基因，检测限为 74 fM，线性响应范围为 0.1-10 pM。此外，该生物传感器表现出优异的特异性，可以区分互补序列和不同的错配序列。在混合杂交体系中，新模式也表现出高灵敏度和选择性。
