Peptide nucleic acid as a sensing probe on nanowire-Field effect transistor (nano-FET) based biosensor

ANYL 445

Shiva K. Rastogi, srastogi@cambr.uidaho.edu, Nirankar N. Mishra, Wusi Maki, Brian Filanoski, Eric Cameron, Paul Winterrowd, and Gary Maki, gmaki@cambr.uidaho.edu. Center for Adavanced Microelectronics and Biomolecular Research (CAMBR), University of Idaho, Research Park (UIRP), 721 Lochsa Str, Ste. 8, Post Falls, ID 83854
Peptide nucleic acid (PNA), a neutral synthetic molecule, was designed as a sensing probe used in electronic nano-biosensors. Specific PNA, Bis-β-Ala-Thymine PNA (bβaPNAs), were synthesized manually using Boc-chemistry on solid phase and purified by RP-HPLC, MALDI-TOF mass spectroscopy was used to characterize purified PNAs. Gel shifting assay was used to analyze hybridization of PNA with oligonucleotide. PNA immobilization on the sensing surface (nano-FET) was investigated. Oligonucleotide captured by PNA on the sensing surface was verified by fluorescent microscopic method. Staphylococcal endotoxin B (SEB) was chosen as target bio-molecule in the detection model. Specific oligonucleotide generated through a signal transduction process, report the presence of SEB. These signal molecules captured by PNA probe on the sensing surface. Electrochemical impedance spectroscopy was used to test changed electronic properties of nano-FET and generate detectable signals. This label free detection method demonstrates the sensitivity achieved at atom molar (10-16 to10-18) level.