【摘要】 为了利用光纤传感器实现对细菌核酸分子的特异性和相对快速检测 ,我们使用直径 1mm的石英光纤和 6 35nm激光二极管 ,利用倏逝波原理制作了光纤生物传感器。光纤经过处理后产生醛基化基团 ,然后与核酸分子进行共价结合。通过 3个实验来验证传感器的特异性和灵敏度。荧光素溶液直接检测 ,使用互补模式寡核苷酸分子 (2 5mer)进行核酸杂交模式实验和设计嗜肺军团菌一段特异性探针与荧光标记嗜肺军团菌染色体DNA杂交。结果表明 :光纤检测荧光素的灵敏度可达 0 0 1nmol L ,而生物芯片扫描仪最低可检测到 1nmol L的荧光素 ;模式寡核苷酸杂交表明 :光纤传感器可以特异性地检出目的核酸分子 ,灵敏度可达纳克级水平 ;染色体杂交结果显示在正常检测浓度下 ,光纤检测军团菌之信噪比达到了 6∶1,同时具有较好的特异性。检测时间约需要 3～ 4h。我们构建的光纤生物传感器可以用于核酸分子的特异性检测 ,并且具有较好的灵敏度 ,对光纤表面修饰、样品处理和杂交过程的优化可望使之应用于实际标本的检测。更多还原

【Abstract】 For the application of the fiber optic biosensor to specific and relative rapid detection of bacterial deoxyribonucleic acid (DNA), we have developed a fiber optic evanescent wave biosensor by using a 1 mm crystal fiber and a 635 nm laser diode. The optical fiber can be chemically modified to produce a silylated surface. Covalent binding occurs when we apply an amino terminal nucleic acid to the surface of the fiber. To test the sensitivity and specificity of the biosensor, three consecutive trials were performed: direct detection of Cy5 dCTP serial dilution, model hybridization of two oligonucleotide probes and oligonucleotide probe hybridization with the target nucleic acid labeled with Cy5 by PCR amplification. The results showed that, the detection limit of biosensor was 0.1 nmol/L for the Cy5 dCTP, whereas the biochip scanner was 1 nmol/L. The model test of a pair of oligonucleotides indicated that the detection limit of oligonucleotides was at a level of nmol/L. As for the detection of L. pneumophila in a recommended concentration, the signal to noise was 6∶1, total detection lasted 4 h compared to the overnight conventional hybridization. We have successfully developed an evanescent wave biosensor the can be applied to the detection of bacterial DNA. Further modification in the treatment of optical fiber, sample preparation and hybridization process may lead to a robust, cost effective and reliable biosensor for real sample detection.更多还原