SARS-CoV-2 spike protein detection through a plasmonic D-shaped plastic optical fiber aptasensor

Abstract

A specific aptameric sequence has been immobilized on short polyethyleneglycol (PEG) interface on gold nano-film deposited on a D-shaped plastic optical fiber (POFs) probe, and the protein binding has been monitored exploiting the very sensitive surface plasmon resonance (SPR) phenomenon. The receptor-binding domain (RBD) of the SARS-CoV-2 spike glycoprotein has been specifically used to develop an aptasensor. Surface analysis techniques coupled to fluorescence microscopy and plasmonic analysis have been utilized to characterize the biointerface. Spanning a wide protein range (25÷1000 nM), the SARS-Cov-2 spike protein was detected with a Limit of Detection (LoD) of about 37 nM. Different interferents (BSA, AH1N1 hemagglutinin protein and MERS spike protein) have been tested confirming the specificity of our aptasensor. Finally, a preliminary test in diluted human serum encouraged its application in a point-of-care device, since POF-based aptasensor represent a potentially low-cost compact biosensor, characterized by a rapid response, a small size and could be an ideal laboratory portable diagnostic tool.

Recent advances in the biosensors application for the detection of bacteria and viruses in wastewater

“…The specificity and sensitivity of the sensor were demonstrated by testing against different interferences, namely BSA, AH1N1 hemagglutinin protein and MERS spike protein. As a result, an LOD of 37 nM was obtained, which is highly comparable to similar reported optical sensor performances in the literature [78] . In general, the sensitivities of optical sensors were significantly lower than those of electrochemical sensors [87] – [85] .…”

“…Several studied investigated optical biosensors for the detection of SARS-CoV-2 [78] – [77] . Cennamo et al reported an optical biosensor for the detection of SARS-CoV-2 using DNA sequences [78] .…”

“…Several studied investigated optical biosensors for the detection of SARS-CoV-2 [78] – [77] . Cennamo et al reported an optical biosensor for the detection of SARS-CoV-2 using DNA sequences [78] . Specific DNA sequences were immobilized on the sensor surface to trigger protein bonding in the presence of the S1 protein, the receptor binding domain.…”

Optical Biomedical Diagnostics Using Lab-on-Fiber Technology: A Review

“…For the clinical cases, the LOD value of the present method was found to be 8.25 × 10 4 copies/mL, whereas ELISA method showed the detection limit of 2.06 × 10 6 copies/mL. Cennamo et al has reported the detection of SARS-CoV-2 spike glycoprotein using a SPR based sensor over D-shaped plastic optical fiber platform [181]. The specific sensing of glycoprotein was achieved using receptor-binding domain (RBD) aptamer of the same SARS-CoV-2 spike glycoprotein target biomolecule.…”

Aptamer Sandwich Assay for the Detection of SARS-CoV-2 Spike Protein Antigen

“…Cennamo et al also used Song’s aptamers in a plasmonic D-shaped plastic optical fiber aptasensor, achieving a detection limit of 37 nM, but the sensor was not applied to the analysis of real samples. 66 Li et al selected an aptamer against the wild-type and B.1.1.7 spike protein and demonstrated the use of the selected aptamers for the detection of a pseudotyped lentivirus in saliva samples, but again, no real samples from individuals with SARS-CoV-2 were analyzed. 51 In another work, the use of aptamer-functionalized gold nanoparticles was reported, achieving a detection limit of 10 nM, which is equivalent to 3540 genome copies/μL of inactivated SARS-CoV-2.…”