Interactions of Hydroxyl Radicals with Tris (Hydroxymethyl) Aminomethane and Good's Buffers Containing Hydroxymethyl or Hydroxyethyl Residues Produce Formaldehyde

The production of formaldehyde from tris(hydroxymethyl) aminomethane(Tris) by interaction with hydroxyl radicals(.OH) was studied, since the reaction mixture from the Fenton reaction performed in Tris/HCl buffer was found to be color-developed by colorimetric determination of formaldehyde. The absorption spectrum of chromogens was identical to that of authentic formaldehyde. Color development, which required the presence of Tris, hydrogen peroxide and cupric ions in the Fenton reaction mixture, was inhibited by the addition of hydroxyl radical scavengers such as glucose or hyaluronic acid. These results indicated that formaldehyde was produced when Tris interacted with ·OH. With structures similar to Tris, Good's buffers were also found to produce formaldehyde by interaction with ·OH. Analysis of formaldehyde derived from these buffers may provide a simple and convenient assay for detecting ·OH generation. In evaluating effects of ·OH on the biological system in Tris/HCl buffer or certain Good's Buffers, ·OH loss may be due to interactions of ·OH with these buffers. The formaldehyde produced as a result of such interactions may affect biological systems.