检测急性早幼粒细胞白血病PML-RARα融合基因的DNA传感器研制

Preparation of DNA Biosensor for Detection of PML-RARα Fusion Gene in Acute Promyelocytic Leukemia

利用共价键合法,将氨基修饰的具有急性早幼粒细胞白血病PML-RARα融合基因特异性的单链DNA探针固定在玻碳电极表面,构成急性早幼粒细胞白血病DNA传感器(急粒DNA传感器)。以电活性的芦荟大黄素(AE)为杂交指示剂,考察了杂交温度及传感器的特异性、重现性和检出限等性能。结果表明:AE在裸电极上的吸附常数为(4.5±0.2)×105L.mol-1,与单链DNA修饰的玻碳电极(ssDNA/GCE)和双链DNA修饰的玻碳电极(dsDNA/GCE)结合常数分别为(2.1±0.4)×105和(2.7±0.2)×105L.mol-1。这种新型的DNA传感器具有特异性强、灵敏度高和重现性好的优点。应用此方法于临床血清分析,初步探索了将该法应用于临床检测的可行性。

A DNA electrochemical sensor was prepared by fixing amino group-modified ssDNA probe with particular DNA sequence of PML-RARα fusion gene in acute promyelocytic leukemia （APL） on the surface of a glassy carbon electrode using covalent bond technology. The response of the sensor to hybridization temperature and the specificity, reproducibility and sensitivity of the sensor were investigatied using Aloe-emodin （AE） as an electroactive indicator. The Langmuir adsorption constants of AE at ssDNA/GCE and dsDNA/GCE were （2.1 ± 0.4） × 10^5 and （2.7± 0.2）×10^5 L·mol^-1 , respectively. The difference between AE at ssDNA/GCE and dsDNA/GCE has been used for the preparation of a sequence-specific DNA electrochemical biosensor, and the electrochemical response for detection of PML-RARα fusion gene in APL has a high specificity, sensitivity and good reproducibility. The method has been evaluated by the determination of the positive/negative standard human serum, and the clinical applicability of the sensor was briefly discussed.