Stability of cocarboxylase in parenteral nutrition mixturesstored in multilayer bags

The aim of this study was to determine the stability of cocarboxylase, a thiamine derivativeemployed as a vitamin B, source in multivitamin additives, in parenteral nutrition (PN) mixtures containing different commercial amino acid infusions. In particular, the influence of a metabisulphite-containing amino acid product, Freamine III®, was investigated. A liquid chromatographic assay method for cocarboxylase was developed and employed to investigate cocarboxylase degradation during extended storage of PN mixtures at 5°C in multilayered bags. Results indicated that cocarboxylase was relatively stable over the 28-day storage period in PN mixtures containing Synthamine® or Vamin® products as amino acid source. In contrast, degradation was accelerated in PN mixtures containing Freamine III®, suggesting that cocarboxylase is degraded by sodium metabisulphite, showing similar sensitivity to thiamine.