Thavanathan Jeevan, Huang Nay Ming, Thong Kwai Lin
Low Dimension Material Research Center, Department of Physics, University of Malaya, Kuala Lumpur, Malaysia.
Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
Int J Nanomedicine. 2015 Apr 2;10:2711-22. doi: 10.2147/IJN.S74753. eCollection 2015.
We have developed a colorimetric biosensor using a dual platform of gold nanoparticles and graphene oxide sheets for the detection of Salmonella enterica. The presence of the invA gene in S. enterica causes a change in color of the biosensor from its original pinkish-red to a light purplish solution. This occurs through the aggregation of the primary gold nanoparticles-conjugated DNA probe onto the surface of the secondary graphene oxide-conjugated DNA probe through DNA hybridization with the targeted DNA sequence. Spectrophotometry analysis showed a shift in wavelength from 525 nm to 600 nm with 1 μM of DNA target. Specificity testing revealed that the biosensor was able to detect various serovars of the S. enterica while no color change was observed with the other bacterial species. Sensitivity testing revealed the limit of detection was at 1 nM of DNA target. This proves the effectiveness of the biosensor in the detection of S. enterica through DNA hybridization.
我们开发了一种比色生物传感器，它使用金纳米颗粒和氧化石墨烯片的双平台来检测肠炎沙门氏菌。肠炎沙门氏菌中invA基因的存在会导致生物传感器的颜色从原来的粉红色变为浅紫色溶液。这是通过与靶向DNA序列进行DNA杂交，使初级金纳米颗粒共轭DNA探针聚集到次级氧化石墨烯共轭DNA探针的表面而发生的。分光光度法分析显示，在存在1 μM DNA靶标的情况下，波长从525 nm移至600 nm。特异性测试表明，该生物传感器能够检测肠炎沙门氏菌的各种血清型，而其他细菌物种未观察到颜色变化。灵敏度测试表明，检测限为1 nM DNA靶标。这证明了该生物传感器通过DNA杂交检测肠炎沙门氏菌的有效性。
