  Nanostructured surfaces enhance ion yields in matrix assisted laser
desorption-ionization mass spectrometry (MALDI-MS). The spike protein complex,
S1, is one fingerprint signature of Sars-CoV-2 with a mass of 75 kDa. Here, we
show that MALDI-MS yields of Sars-CoV-2 spike protein ions in the 100 kDa range
are enhanced 50-fold when the matrix-analyte solution is placed on substrates
that are coated with a dense forest of multi-walled carbon nanotubes, compared
to yields from uncoated substrates. Nanostructured substrates can support the
development of mass spectrometry techniques for sensitive pathogen detection
and environmental monitoring.
