Chemical derivatization technique in ToF-SIMS for quantification analysis of surface amine groups

A chemical derivatization technique in ToF-SIMS along with principal component analysis (PCA) were used to perform a quantitative study of the surface amine density of the plasma-polymerized ethylenediamine (PPEDA) thin film. We used the scores on principal component (PC) 1 from a PCA of ToF-SIMS data for the PPEDA films and their chemical-derivatized surfaces for comparison with the surface amine densities. These surface amine densities were independently determined by UV-visible spectroscopy. Our work found a good linear relationship between the surface amine densities and the scores on PC 1 from a PCA of the ToF-SIMS data for the chemical-derivatized PPEDA surfaces, but not for the PPEDA thin films themselves. In addition to quantification, our PCA results provided insights into the surface chemical composition of each surface.