Label-free direct electronic detection of biomolecules with amorphous silicon nanostructures.
We present the fabrication and characterization of a nano-scale sensor made of amorphous silicon for the label-free, electronic detection of three classes of biologically important molecules: ions, oligonucleotides, and proteins. The sensor structure has an active element which is a 50 nm wide amorphous silicon semicircle and has a total footprint of less than 4 microm2. We demonstrate the functionalization of the sensor with receptor molecules and the electronic detection of three targets: H(+) ions, short single-stranded DNAs, and streptavidin. The sensor is able to reliably distinguish single base-pair mismatches in 12 base long strands of DNA and monitor the introduction and identification of straptavidin in real-time. The versatile sensor structure can be readily functionalized with a wide range of receptor molecules and is suitable for integration with high-speed electronic circuits as a post-process on an integrated circuit chip.
Lund
John
J
Department of Electrical Engineering, University of Washington, Seattle, Washington 98195-2500, USA.
Mehta
Ranjana
R
Parviz
Babak A
BA
D015415:Biomarkers / Q000737:chemistry; D015374:Biosensing Techniques; D004581:Electronics; D004583:Electrons; D004867:Equipment Design; D006801:Humans; D007477:Ions; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry*; D049329:Nanostructures; D036103:Nanotechnology / Q000379:methods*; D020411:Oligonucleotide Array Sequence Analysis; D009841:Oligonucleotides / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D019809:Streptavidin / Q000737:chemistry
D015415:Biomarkers; D007477:Ions; D009841:Oligonucleotides; D019809:Streptavidin; D012825:Silicon