I'm thinking is one of the key things is getting a plasmon poloriton surface of 10nanometers or less will be needed to effectively snag these buggers.
Tomorrow spending some time trying to model the volume of these individual virus I think the exact size is known and they pretty darn tiny hence the 10 namometers or smaller
The Covid virus (SARS-CoV-2) is thought to be 70-90 nm in size.
It’s in the “2. Analysis of the structure of the virus by electron micrographs” section of this artice:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045880/