Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7229412 | Biosensors and Bioelectronics | 2018 | 29 Pages |
Abstract
This work reports on a molybdenum disulfide (MoS2) based field-effect transistor (FET) biosensor for ultrasensitive label-free detection of DNA via phosphorodiamidate morpholino oligos (PMO)-DNA hybridization. After the chip was fabricated and the sensing channel was modified with positive charges, the negatively charged MoS2 nanosheet was drop-casted onto the channel, enabling MoS2 to tightly bind to the sensing surface via electrostatic interactions. Meanwhile, DNA analogue, PMO, was immobilized on the MoS2 surface, and detection of PMO-DNA hybridization was conducted by the fabricated MoS2 FET biosensor. Due to the neutral character and high affinity of PMO, a limit of detection (LOD) down to 6 fM was obtained, which is lower than that of the previously reported MoS2 FET DNA biosensor based on DNA-DNA hybridization. In addition, the MoS2 FET biosensor also showed high sequence specificity capable of distinguishing the complementary DNA from one-base mismatched DNA, three-base mismatched DNA and noncomplementary DNA. Moreover, the unique FET biosensor was able to detect DNA in complex sample like serum, making the method potential in disease diagnostics.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Junchi Mei, Yu-Tao Li, Hong Zhang, Meng-Meng Xiao, Yong Ning, Zhi-Yong Zhang, Guo-Jun Zhang,