3D-printed electrode as a new platform for electrochemical immunosensors for virus detection

Abstract

Simple, low-cost, and sensitive new platforms for electrochemical immunosensors for virus detection have been attracted attention due to the recent pandemic caused by a new type of coronavirus (SARS-CoV-2). In the present work, we report for the first time the construction of an immunosensor using a commercial 3D conductive filament of carbon black and polylactic acid (PLA) to detect Hantavirus Araucaria nucleoprotein (Np) as a proof-of-concept. The recognition biomolecule was anchored directly at the filament surface by using N -(3-Dimethylaminopropyl)- N ′-ethylcarbodiimide hydrochloride and N -Hydroxysuccinimide (EDC/NHS). Conductive and non-conductive composites of PLA were characterized using thermal gravimetric analysis (TGA), revealing around 30% w/w of carbon in the filament. Morphological features of composites were obtained from SEM and TEM measurements. FTIR measurement revealed that crosslinking agents were covalently bonded at the filament surface. Electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for the evaluation of each step involved in the construction of the proposed immunosensor. The results showed the potentiality of the device for the quantitative detection of Hantavirus Araucaria nucleoprotein (Np) from 30 μg mL −1 to 240 μg mL −1 with a limit of detection of 22 μg mL −1 . Also, the proposed immunosensor was applied with success for virus detection in 100x diluted human serum samples. Therefore, the PLA conductive filament with carbon black is a simple and excellent platform for immunosensing, which offers naturally carboxylic groups able to anchor covalently biomolecules.

3D-Printed COVID-19 immunosensors with electronic readout

“… [3] from Supporting Information). Importantly, some pivotal electroanalytical parameters achieved by this 3D-printed G/PLA electrode, such as LOD (0.5 μg·mL -1 ), lineal range (1.0 to 10 μg·mL -1 ) and reproducibility (error bars), were significantly improved with respect to those obtained by the only alternative 3D-printed immunosensing device —made of carbon black/PLA— reported to date (LOD of 22 μg·mL -1 and lineal range from 30 to 240 μg·mL -1 for the determination of the Hantavirus Araucaria nucleoprotein) [32] . However, since 3D-printing technology is still in early stages, further research is highly encouraged in light of this promising cross-disciplinary field.…”

“…Such capability is especially important when dealing with urgent global pandemic. Nonetheless, the use of this technology for immunosensing approaches is almost an unexplored field, with only one published work [32] . This fact can be mainly ascribed to the lack of robust biofunctionalization methods for tuning 3D-printed transducers, being mainly limited to the use of weak physisorption or costly sputtering processes [33] .…”

Electrochemical immunosensors using electrodeposited gold nanostructures for detecting the S proteins from SARS-CoV and SARS-CoV-2

“…Electrochemical sensors with a set of electrodes, viz. working (WE), reference (RE), and counter (CE) electrodes, allow for multi-target detection, simple arrays, portability, and fast responses, being ideal for applications in situ [2,11,12]. Analytes can be detected and quantified through redox reactions when binding occurs between the target and the biorecognition element [13], and, therefore, the sensing performance depends strongly on the WE material [14,15].…”

Versatile Design of Functional Organic–Inorganic 3D‐Printed (Opto)Electronic Interfaces with Custom Catalytic Activity

“…Surface engineering has been responsible to light up different nanocomposites made of both inorganic and organic components for their custom application in extremely divers fields. [1,2,3,4,5] Particularly, the use of functional inorganic nanoparticles (FINPs) has received considerable attention owing to their catalytic and electrochemical features, providing great and polylactic acid (PLA) are being extensively used for several electrochemical applications, including electroanalysis, [28,29,30,31] energy (storage and conversion) [32,33,34,35] and switching memories. [36] However, a main limitation when using 3D-nCEs can be clearly identified: the lack of effective (bio)functionalization methods for tuning their functional capabilities, being mainly limited to the use of weak physisorption or costly sputtering processes.…”