Biomimetic nanochannels based biosensor for ultrasensitive and label-free detection of nucleic acids

• Published in: Biosensors & bioelectronics Vol. 86; pp. 194 - 201
• Main Authors: Sun, Zhongyue, Liao, Tangbin, Zhang, Yulin, Shu, Jing, Zhang, Hong, Zhang, Guo-Jun
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.12.2016
• Subjects: Biomimetic Materials - chemistry; Biomimetics; Biosensor; Biosensors; Conductometry - instrumentation; Deoxyribonucleic acid; DNA; DNA - analysis; DNA - genetics; DNA Probes - chemistry; DNA Probes - genetics; Equipment Design; Equipment Failure Analysis; Hybridization; Immobilization; Ion Channels - chemistry; Label-free detection; Molecular Probe Techniques - instrumentation; Nanochannels; Nanopores - ultrastructure; Nanostructure; Nanostructures - chemistry; Nanostructures - ultrastructure; Reproducibility of Results; Sensing devices; Sensitivity and Specificity; Sensors; Sequence Analysis, DNA - instrumentation; Staining and Labeling; Target detection; Nanochannels; Label-free detection; Hybridization; Biosensor; DNA
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2016.06.059

A very simple sensing device based on biomimetic nanochannels has been developed for label-free, ultrasensitive and highly sequence-specific detection of DNA. Probe DNA was modified on the inner wall of the nanochannel surface by layer-by-layer (LBL) assembly. After probe DNA immobilization, DNA detection was realized by monitoring the rectified ion current when hybridization occurred. Due to three dimensional (3D) nanoscale environment of the nanochannel, this special geometry dramatically increased the surface area of the nanochannel for immobilization of probe molecules on the inner-surface and enlarged contact area between probes and target-molecules. Thus, the unique sensor reached a reliable detection limit of 10 fM for target DNA. In addition, this DNA sensor could discriminate complementary DNA (c-DNA) from non-complementary DNA (nc-DNA), two-base mismatched DNA (2bm-DNA) and one-base mismatched DNA (1bm-DNA) with high specificity. Moreover, the nanochannel-based biosensor was also able to detect target DNA even in an interfering environment and serum samples. This approach will provide a novel biosensing platform for detection and discrimination of disease-related molecular targets and unknown sequence DNA. •3-D nanochannel-based biosensor for DNA detection has been proposed.•DNA-DNA hybridization has been employed to realize label-free and sensitive detection of DNA by using fabricated nanochannel.•The fabricated nanochannel is able to detect DNA in interfering system and serum sample.•High sensitivity has been achieved based on this detection system.•The developed sensing platform shows good sequence discrimination.