Varying amounts of different aldehydes present in the cryoprotectants dimethyl sulphoxide and 1,2-propanediol

Using high-pressure liquid chromatography two cryoprotectant solvents, dimethyl sulphoxide (four manufacturers) and 1,2-propanediol (one manufacturer) were investigated for aldehyde content. Fractionation of the aldehydes by high pressure liquid chromatography identified up to 11 aldehydes and two ketones in both cryoprotectant solvents in varying concentrations, which differed between manufacturer and container type. Of the 11 aldehydes identified, formaldehyde and acetylaldehyde were consistently in the greatest concentrations. As the low molecular weight aldehydes identified contain reactive polarised carbonyl groups they represent a potential source of intracellular damage when used in oocyte cryopreservation.