Ultrasensitive Detection of COVID-19 Causative Virus (SARS-CoV-2) Spike Protein Using Laser Induced Graphene Field-Effect Transistor

Abstract

COVID-19 is a highly contagious human infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the war with the virus is still underway. Since no specific drugs have been made available yet and there is an imbalance between supply and demand for vaccines, early diagnosis and isolation are essential to control the outbreak. Current nucleic acid testing methods require high sample quality and laboratory conditions, which cannot meet flexible applications. Here, we report a laser-induced graphene field-effect transistor (LIG-FET) for detecting SARS-CoV-2. The FET was manufactured by different reduction degree LIG, with an oyster reef-like porous graphene channel to enrich the binding point between the virus protein and sensing area. After immobilizing specific antibodies in the channel, the FET can detect the SARS-CoV-2 spike protein in 15 min at a concentration of 1 pg/mL in phosphate-buffered saline (PBS) and 1 ng/mL in human serum. In addition, the sensor shows great specificity to the spike protein of SARS-CoV-2. Our sensors can realize fast production for COVID-19 rapid testing, as each LIG-FET can be fabricated by a laser platform in seconds. It is the first time that LIG has realized a virus sensing FET without any sample pretreatment or labeling, which paves the way for low-cost and rapid detection of COVID-19.

The role of electrochemical biosensors in SARS-CoV-2 detection: a bibliometrics-based analysis and review

“…Field-effect transistors (FETs) can also be used in combination with immunoassays for S-protein detection. Cui et al 67 prepared FET using laser-induced graphene and immobilized specific antibodies. The FET can achieve detection limits of 1 pg mL −1 and 1 ng mL −1 in PBS and human serum, respectively.…”

Laser-Induced Graphene (LIG) as a Smart and Sustainable Material to Restrain Pandemics and Endemics: A Perspective

“…The LIG-FET has shown high sensitivity with detection limits of up to 1 pg/mL, which are quite high as compared to previously made graphene-based FETs. 144 Along with electrochemical sensing, the optical sensing property could also be explored via photoluminescence. The nucleic acid could be incorporated with fluorescent dyes that can be quenched by graphene via nucleic acid adsorption to the surface.…”

“…This technique showed excellent reliability and effectiveness with regard to the current situation. The electrochemical process could also be extrapolated to environmental samples such as soil, as investigated by Garland et al In addition to this, people have started exploring field-effect transistors (FETs) for the detection of COVID-19 protein spikes. , Cui et al fabricated a LIG-based FET via multiple degrees of laser reduction, which formed oyster reef-like graphene channels. A liquid ion gate FET was formed, which modulated the carrier concentration of antibodies in the channel.…”

Advancement and Challenges of Biosensing Using Field Effect Transistors

“…The sensor is not only found to be highly sensitive in detecting a 1 fg/mL concentration of SARS-CoV-2 spike protein but also highly specific in not responding to a related coronavirus strain such as MERS-CoV spike protein. A similar type of detection methodology was also carried out by Cui et al with laser induced GFET, which detected 1 pg/mL of SAR-CoV2 spike protein and also exhibited good specificity in responding only to the spike protein and no significant response to non-complementary nucleocapsid proteins [ 52 ]. Other kinds of viruses such as the Japanese encaphalitis virus (JEV) and the Avian influenza virus (AIV) are also detected efficiently by this method [ 53 ].…”