1. Label-free electronic detection of bio-toxins using aligned carbon nanotubes
- Author
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W.H. Goh, Derrick Wen Hui Fam, B.J. Hanson, Shabbir Moochhala, Al. Palaniappan, Subodh Mhaisalkar, C.E.Z. Chan, G. Rajaseger, and Bo Liedberg
- Subjects
Fabrication ,Materials science ,Conductometry ,Transistors, Electronic ,Bacterial Toxins ,Biomedical Engineering ,Biophysics ,Nanotechnology ,Food Contamination ,Carbon nanotube ,Biosensing Techniques ,law.invention ,chemistry.chemical_compound ,symbols.namesake ,law ,Electrochemistry ,Orange juice ,Polydimethylsiloxane ,Staining and Labeling ,Nanotubes, Carbon ,General Medicine ,Equipment Design ,Equipment Failure Analysis ,chemistry ,symbols ,Surface modification ,Field-effect transistor ,Raman spectroscopy ,Biosensor ,Food Analysis ,Biotechnology - Abstract
A facile route for sensitive label-free detection of bio-toxins using aligned single walled carbon nanotubes is described. This approach involves patterning of a catalyst on the surface of a quartz substrate using a sub-100 μm stripe-patterned polydimethylsiloxane stamp for aligned carbon nanotube generation followed by fabrication of field effect transistor (FET). Atomic force microscopy, field emission scanning electron microscopy and Raman spectroscopy are employed to characterize the synthesized nanotubes. Unlike previous reports, the adopted approach enables direct electronic detection of bio-toxins with sensitivities comparable to ELISA. As a proof of concept, the fabricated FET responds to nM concentration levels (with a LOD of ∼2 nM) of epsilon toxin produced by Clostridium perfringens and a prominent food toxin. This facile approach could be customized to detect other classes of toxins and biomarkers upon appropriate functionalization of the aligned carbon nanotubes. Finally, we demonstrate the use of the FET-platform for detection of toxin in more complex matrices such as orange juice.
- Published
- 2012