Cy5标记的DNA荧光毛细生物传感器的研究

Study on DNA Fluorescence Capillary Biosensor Labeled with Cy5

探索了以Cy5（吲哚-5-菁）作为荧光标记物的DNA荧光毛细生物传感器的可行性。以荧光毛细分析法（fluorescencecapillary analysis,FCA）为基础,在毛细管内壁通过poly-l-lysine将20-mer-ss DNA探针固定,制成DNA荧光毛细生物传感器（DNA fluorescence capillary biosensor,DNA-FCB）,DNA-FCB吸入含Cy5标记的靶DNA液杂交,通过检测杂交产物的荧光强度,实现对靶DNA的定性和定量分析。结果显示,样品用量5μL,Cy5标记的靶DNA浓度在0.2~1.2μmol/L（2.4~24mg/L）范围内和荧光强度有良好的线性关系（Y=129.61X＋21.233,r=0.9970）;RSD〈3.5%;检出限为0.18μmol/L。结论：以Cy5作为荧光标记物的DNA荧光毛细生物传感器能达到定量检测靶DNA的目的。该方法操作简便,试样、试剂用量少,毛细管及DNA-FCB可循环使用,测定成本极低,能大大减少环境污染。

To investigate the feasibility of DNA fluorescence capillary biosensor labeled with Cy5,based on fluorescence capillary analysis（FCA）,the DNA biosensor using capillary as immobilization and detection carrier of DNA probe（20-mer-ssDNA） were immobilized on the inner wall of capillary by poly-l-lysine to make DNA fluorescence capillary biosensor（DNA-FCB）.The DNA-FCB was hybridized with complementary target DNA labeled by Cy5.The target DNA was qualified or quantified by detecting the fluorescent density of the Cy5 using F-4500 spectrofluorometer.The results showed that the concentration of the target DNA had good linearity with the fluorescent intensity in range of 0.2～1.2μmol/L when sample volume was 5μL.RSD was lower than 3.5%.The concentration detection limit of the target DNA was 0.39μmol/L.The DNA-FCB can be used to qualify or quantify the target DNA.DNA-FCB is simple with advantages of lower sample and reagent volumes,repeated use of capillary,the lowest test cost,and reduce the pollution to environment.