Review—Role of Nanomaterials in Screenprinted Electrochemical Biosensors for Detection of Covid-19 and for Post-Covid Syndromes

Abstract

Covid-19 remains a global pandemic surging with different variants like (Omicron) in various countries. An escalation in random testing for Covid-19 is considered as the golden standard by WHO to control the spread of Corona virus. RT-PCR and nucleic acid hybridization strategies are two highly sensitive outstanding tests used for the detection of SARS-CoV-2 in the DNA by the former and RNA/DNA by the later. Apart from the test for virus, antigen, and antibodies, other alternative hematological tests like CRP, Ferritine, IL-6, Blood Platelets and WBC, and plasma became essential for the detection and management of Covid-19. Overcoming the limitations of a rapid, efficient, low-cost, and easy-to-implement test kits are in imperative need to meet these requirements. Electrochemical sensors are considered as potential and ultrafast point-of-care sensors used as self-testing kits. In this work, we review the various modified electrodes with different nanomaterials such as graphene, CNTs, and nano-dopants used as electrochemical sensors in association with testing various different parameters for detection of covid-19. A detailed discussion on the merits of present testing patterns and scope of screen-printed electrochemical sensors modified with different nanomaterials and their advantages is presented.

Biolayer-Interferometry-Guided Functionalization of Screen-Printed Graphene for Label-Free Electrochemical Virus Detection

“…In contrast, screen printing (SP) offers scalable and low-cost production with the potential for high reproducibility, especially with suitably chosen postprocessing methods. 31,32 In particular, graphene SP electrodes have been widely employed in biosensing platforms for diverse targets including C-reactive proteins for early detection of cardiovascular disease, viral detection even before the COVID-19 pandemic, and broadly understood food safety measures. 33 Screen-printed electrodes are often subjected to surface modification with other materials such as metallic nanoparticles (e.g., copper 31,32,34 and gold 31,32,35 ), transition metal dichalcogenides (e.g., molybdenum disulfide 31,32 and tungsten oxide 31,32 ), conductive polymers (e.g., polyaniline 31,32,36 and polypyrole 31,32,37 ), quantum dots, 31,32,38 and other carbonbased materials.…”

“…Screen-printed electrodes are often subjected to surface modification with other materials such as metallic nanoparticles (e.g., copper ,, and gold ,, ), transition metal dichalcogenides (e.g., molybdenum disulfide , and tungsten oxide , ), conductive polymers (e.g., polyaniline ,, and polypyrole ,, ), quantum dots, ,, and other carbon-based materials. ,, When utilized individually or in combination, these surface modifications result in enhanced sensitivity and/or more efficient immobilization of the recognition agent, , the latter of which is often additionally aided by electrochemical activation . Although these surface modification methods can improve sensor performance, they require additional processing, which elevate production costs and limit manufacturing scalability.…”

“…31,32 In particular, graphene SP electrodes have been widely employed in biosensing platforms for diverse targets including C-reactive proteins for early detection of cardiovascular disease, viral detection even before the COVID-19 pandemic, and broadly understood food safety measures. 33 Screen-printed electrodes are often subjected to surface modification with other materials such as metallic nanoparticles (e.g., copper 31,32,34 and gold 31,32,35 ), transition metal dichalcogenides (e.g., molybdenum disulfide 31,32 and tungsten oxide 31,32 ), conductive polymers (e.g., polyaniline 31,32,36 and polypyrole 31,32,37 ), quantum dots, 31,32,38 and other carbonbased materials. 31,32,39 When utilized individually or in combination, these surface modifications result in enhanced sensitivity and/or more efficient immobilization of the recognition agent, 40,41 the latter of which is often additionally aided by electrochemical activation.…”

“…Electrochemical sensors frequently employ electrodes consisting of nanostructured carbon materials, , such as graphene, graphene oxide, carbon nanotubes, carbon quantum dots, or fullerenes, ,, due to their large surface-area-to-volume ratios, solution processability that enables rapid additive manufacturing, and established functionalization schemes. , Despite these advantages of carbon nanomaterials, deposition methods strongly influence film morphology, resulting in challenges with reproducibility. ,, Common deposition and printing processes include drop-casting, spin-coating, stamping, aerosol jet printing (AJP), inkjet printing, and 3D printing, ,,− each of which results in a different film morphology, thickness, roughness, and resolution, all of which can affect electrochemical performance. In contrast, screen printing (SP) offers scalable and low-cost production with the potential for high reproducibility, especially with suitably chosen postprocessing methods. , In particular, graphene SP electrodes have been widely employed in biosensing platforms for diverse targets including C-reactive proteins for early detection of cardiovascular disease, viral detection even before the COVID-19 pandemic, and broadly understood food safety measures …”

Mechanical and spectroscopic investigation of novel f-MWCNTS/g-C3N4/TiO2 ternary nanocomposite reinforced denture base PMMA

“…Non-covalent functionalization is generally performed to absorb the drug molecules on the surface of the CNTs done by hydrophobic and π-π stacking interactions between the CNTs surface and the adsorbed molecule chains [24]. Proteins, enzymes, DNA, dyes, polymers, dendrimers, and β-cyclodextrins are introduced onto the surfaces of the CNTs through non-covalent functionalization [25]. In the present work, carboxyl functional groups were attached to the surface and ends of the MWCNTs by covalent functionalization attained by reflux of HNO 3 and H 2 SO 4 [26].…”