Real-time wash-free detection of unlabeled PNA-DNA hybridization using discrete FET sensor.

ABSTRACT: We demonstrate an electrochemical sensor for detection of unlabeled single-stranded DNA using peptide nucleic acid (PNA) probes coupled to the field-effect transistor (FET) gate. The label-free detection relies on the intrinsic charge of the DNA backbone. Similar detection schemes have mainly concentrated on sensitivity improvement with an emphasis on new sensor structures. Our approach focuses on using an extended-gate that separates the FET and the sensing electrode yielding a simple and mass fabricable device. We used PNA probes for efficient hybridization in low salt conditions that is required to avoid the counter ion screening. As a result, significant part of the target DNA lies within the screening length of the sensor. With this, we achieved a wash-free detection where  typical ga

SUBMITTER: Kaisti M 

PROVIDER: S-EPMC5691077 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature