Investigation of Protein Detection Parameters Using Nanofunctionalized Organic Field-Effect Transistors

Abstract

Biodetection using organic field-effect transistors (OFETs) is gaining increasing interest for applications as diverse as food security, environmental monitoring, and medical diagnostics. However, there still lacks a comprehensive, empirical study on the fundamental limits of OFET sensors. In this paper, we present a thorough study of the various parameters affecting biosensing using an OFET decorated with gold nanoparticle (AuNP) binding sites. These parameters include the spacing between receptors, pH of the buffer, and ionic strength of the buffer. To this end, we employed the thrombin protein and its corresponding DNA binding aptamer to form our model detection system. We demonstrate a detection limit of 100 pM for this protein with high selectivity over other proteases in situ. We describe herein a feasible approach for protein detection with OFETs and a thorough investigation of parameters governing biodetection events using OFETs. Our obtained results should provide important guidelines to tailor the sensor's dynamic range to suit other desired OFET-based biodetection applications.

Highly stable organic polymer field-effect transistor sensor for selective detection in the marine environment

“…Remarkably, the high background concentration of salt in seawater (B600 mM) has only little effect on the interaction between Hg 2 þ and the OFET 53 compared with the interaction in DI water, allowing a detection limit down to 10 mM (Supplementary Figs S21 and S22 and Supplementary Note 4). This detection limit may be improved by decreasing the spacing between the AuNPs, to increase the density of the attached DNA 54 . In this work, the main goal of Hg 2 þ detection is to demonstrate that selective sensing is possible with OFET sensors even in high salt concentration seawater.…”

Single Crystal‐Like Performance in Solution‐Coated Thin‐Film Organic Field‐Effect Transistors

“…[50][51][52] A series of devices were dipped in mq-water for different time periods. After each immersion the device was blown with N 2 to remove any water droplets, and subsequently, they were electrically characterized.…”

Electrolytic Gated Organic Field-Effect Transistors for Application in Biosensors—A Review

“…As an example of what could be done, Poghossian et al, not in an organic-based but in a silicon-based device, reported a gating capacitive field-effect sensor [108] for detection of charged molecules using gold NPs to increase the capacitive effect ( Figure 18). Bao's group also reported biodetection using a classical bottom-gate OFET decorated with gold nanoparticles, which were used to vary spacing between receptors [109]. …”