Conjugation of Single-Chain Variable Fragment Antibody to Magnetic Nanoparticles and Screening of Fig Mosaic Virus by MALDI TOF Mass Spectrometry

The
ability of mass spectrometry for discrimination between protein
and peptide masses which are unique to specific pathogens provides
an accurate and fast method for the detection of different types of
pathogens, especially viruses. Capsid proteins are specific to each
virus and can be used as a biomarker for detection of this pathogen.
On the other hand, single-chain variable fragment (scFv) antibodies
have been recently used to enhance the accuracy of immunoassay techniques.
So conjugation of mass spectrometry and scFv antibody provides a very
accurate and fast method for the detection of viruses. In this report,
for the first time, we have immobilized scFv antibody of fig mosaic
virus (FMV) on the magnetic nanoparticles (MNPs) to extract the virus
capsid protein from complex biological media and subsequently identified
this protein through both its intact molecular mass and peptide mass
fingerprint (PMF) by matrix-assisted laser desorption/ionization time-of-flight
mass spectrometry (MALDI-TOF MS).