Use of poly(tetrafluoroethylene)s as a sample support for the MALDI-TOF analysis of DNA and proteins

Matrix-assisted laser desorption/ionization mass spectrometry of DNA and proteins, directly deposited on the poly(tetrafluoroethylene) (Teflon) surface, is demonstrated. For DNA analysis, this technique apparently produces a more homogeneous coverage of the matrix/DNA over the sample surface. Moreover, it enhances the sensitivity and salt tolerance. As described here, this technique can also achieve an excellent mass resolution, similar to that observed using a metal probe for DNA up to 62mer. We also examined the use of Teflon as a sample support for protein analysis since Teflon has been used as a transfer membrane. Less than 25 fmol of myoglobin has been detected with this technique. In addition, effective MALDI-TOF analysis of salt-contaminated protein samples can also be accomplished by loading the protein sample onto Teflon, followed by steps of washing away salts, adding the matrix, and desorbing sample directly from Teflon.