The present research provides a theoretical investigation on applying pristine B3O3 nanosheet for sensory properties toward the ethyl butyrate biomarker to identify COVID-19 via exhaling breathing of lungrelated diseases. This research shows that this nanostructure is an excellent substrate for the sense of ethyl butyrate biomarker, with energy adsorption in the range of 2.421 to 15.243 kcal/mol and desired recovery time 12.7 10-3 s. In addition to detecting COVID-19 from the patient’s breath, this nanosheet can also deliver a Baricitinib drug to the target tissue to treat COVID-19. The interaction between carriers and drug indicates that adsorptions of the drug over B3O3 nanosheet are energetically favorable with energy adsorption in the range 5.788 to 40.009 kcal/mol in the gas phase 4.035 to 17.272 kcal/mol in water media with a significant percentage of changes in the band gap of the desired monolayer in considered systems. It is shown that Baricitinib can be released from the chosen carriers while apprising a weak external electric field of 0.001 and 0.002 eVÅ1 e-1 in the opposite of y-direction. The drug/B3O3 complex reaction toward the external electric field is promising for developing efficient targeting drug delivery
