"A combination of inverse gas-liquid chromatography (IGLC) and time-of-flight mass spectroscopy was shown to be effective in demonstrating changes in asphalts resulting from oxidation and silylation. Most test compounds emerged unaltered from IGLC columns containing the asphalt samples. Some acidic and basic test compounds provided silyl exchange products on silylated columns. Primary and secondary amines provided water from reaction with oxidized asphalt samples. Results using the various asphalts demonstrated differences between samples."