Printable graphene BioFETs for DNA quantification in Lab-on-PCB microsystems

Abstract

Lab-on-Chip is a technology that aims to transform the Point-of-Care (PoC) diagnostics field; nonetheless a commercial production compatible technology is yet to be established. Lab-on-Printed Circuit Board (Lab-on-PCB) is currently considered as a promising candidate technology for cost-aware but simultaneously high specification applications, requiring multi-component microsystem implementations, due to its inherent compatibility with electronics and the long-standing industrial manufacturing basis. In this work, we demonstrate the first electrolyte gated field-effect transistor (FET) DNA biosensor implemented on commercially fabricated PCB in a planar layout. Graphene ink was drop-casted to form the transistor channel and PNA probes were immobilized on the graphene channel, enabling label-free DNA detection. It is shown that the sensor can selectively detect the complementary DNA sequence, following a fully inkjet-printing compatible manufacturing process. The results demonstrate the potential for the effortless integration of FET sensors into Lab-on-PCB diagnostic platforms, paving the way for even higher sensitivity quantification than the current Lab-on-PCB state-of-the-art of passive electrode electrochemical sensing. The substitution of such biosensors with our presented FET structures, promises further reduction of the time-to-result in microsystems combining sequential DNA amplification and detection modules to few minutes, since much fewer amplification cycles are required even for low-abundance nucleic acid targets.

Ultra‐Flexible Biodegradable Pressure Sensitive Field Effect Transistors for Hands‐Free Control of Robot Movements

“…The obtained ON/OFF ratio in our proposed device S4 was higher than that reported in works. [12,13,15] However, the GFNs show increased resistivity and reduced mobility due to the diffusive transport of charge carriers along and across the curved (strained) regions. [76] The ON/OFF ratio was reduced for GO concentration >0.5 wt%, as observed for samples S5 and S6.…”

“…As a result, their application was restricted to the FET-based sensors. [12][13][14][15] This could be addressed through the utilization of nanostructured crumpled GFN as the channel material. [16] The nanocorrugations in GFN morphology produce a bandgap (800 meV) opening in its electronic structure.…”

Biomolecular control over local gating in bilayer graphene induced by ferritin

“…Mostly, ferritin is adsorbed on gold electrodes via modification of ferritins with thiol containing amino acids (cysteine) followed by deposition on Au or by first forming a linker monolayer on Au followed by deposition of ferritin (Kim et al, 2007;Won et al, 2008;Frasconi et al,2010). Here, we directly adsorbed AfFtn-AA on graphene where AfFtn-AA readily binds to graphene likely via electrostatic interactions (as discussed in the main text) in addition to non-specific interactions (including amines exposed at the periphery that may interact strongly with graphene (Mulyana et al,2016a(Mulyana et al, , 2016bSong et al, 2016;Papamatthaiou et al,2021). Figure S4 shows additional AFM images and the height profiles corresponding to the white lines.…”

DNA Studies: Latest Spectroscopic and Structural Approaches

“…Systematic positive shifts of the channel current over the voltage gate curve were obtained with increasing complementary DNA concentrations (from 100 pM to 1 μM). The LOD of this device is still lower (1 nM) compared to more established techniques [ 72 ], given the absence of micro-fluidic integration. However, this work is the starting point for the development of Lab-on-PCB, which proposes the integration of electronics, sensing, fluidic channels, and packaging by well-established PCB protocols.…”

“…Optical detection [64,65] Electrochemical detection [66][67][68][69][70][71][72] High resolution melting analysis Structural studies [73,74] Microscopic approaches…”