Minimum ignition energy of amino acids and their Fmocs

Abstract

Fmoc groups are base labile functional groups attached to amino acids to reduce undesirable reactions in peptide synthesis. As with ordinary amino acids, Fmoc-protected amino acid dusts are combustible, and exhibit the potential for a dust explosion. Dust explosions are a continuing challenge in the process industries and has been the subject of much research. Industrial dusts are usually evaluated for explosion hazard probability on the basis of their minimum ignition energy, the minimum energy an ignition source must supply in order to ignite a dust cloud. Such data is often used in risk assessments and to compare combustible dusts to each other, but there is a lack of data in the literature for minimum ignition energies for both ordinary amino acid dust and Fmoc-protected amino acid dusts. This study experimentally determined minimum ignition energies for the following amino acids and their corresponding Fmoc-protected versions: L-serine, L-proline, glycine, L-glutamic acid, and L-alanine. By comparing the Fmoc-protected amino acid dusts to their ordinary amino acid counterpart, it becomes apparent that the protected variants are much more combustible than the parent molecules. From a perspective of loss prevention, this publication attempts to bring immediate awareness and takes the first step in filling a gap in the published information addressing this topic and contextualize these findings as they pertain to process safety.