Abstract
| - Using MS/MS, we have identified ions at m/z 399,421,609.4, and 819.9 as those of tris(2-butoxyethyl) phosphate, originating in the gray rubber stoppers commonlyused as closures in commercial sources of peptides andproteins. The compound is readily extracted bycontactwith organic solvents such as alcohol or acetic acid andeven by water alone. Zinc salts of proteins are alsoobserved, presumably from zinc oxide fillers present inthe stoppers.
|