Monitoring DNA Hybridization with Organic Electrochemical Transistors Functionalized with Polydopamine

• Organic electrochemical transistors (OECTs) are finding widespread application in biosensing, thanks to their high sensitivity, broad dynamic range, and low limit of detection. An OECT biosensor requires the immobilization of a biorecognition probe on the gate, or else on the channel, through several, often lengthy, chemical steps. In this work, a fast and straightforward way to functionalize the carbon gate of a fully screen-printed OECT by means of a polydopamine (PDA) film is presented. By chemical immobilization of an amine-terminated single-stranded oligonucleotide, containing the HSP70 promoter CCAAT sequence, on the PDA film, the detection of the complementary DNA strand is demonstrated. Furthermore, the specificity of the developed genosensor is assessed by comparing its response to the fully complementary strand with the one to partially complementary and noncomplementary oligonucleotides. The developed sensor shows a theoretical limit of detection (LOD) of 100 × 10−15 m and a dynamic range over four orders of magnitude. © 2022 The Authors.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

genosensors

OECTs

organic electronics

polydopamine

Chemical detection

Transistors

Biosensing

DNA hybridization

Dynamic range limits

Functionalized

High sensitivity

Lower limits of detections

Organic electrochemical transistors

Oligonucleotides

Publication and Content Type

ref (subject category)

art (subject category)