A NOVEL DERIVATIZATION OF ETHYLENE-GLYCOL FROM HUMAN SERUM USING 4-CARBETHOXYHEXAFLUOROBUTYRYL CHLORIDE FOR UNAMBIGUOUS GAS-CHROMATOGRAPHY CHEMICAL-IONIZATION MASS-SPECTROMETRIC IDENTIFICATION AND QUANTIFICATION

Ethylene glycol poisoning is a common problem and identification of et hylene glycol in serum is important for both medical and legal purpose s. Other glycols like propylene glycol, 2,3-butanediol, and diethylene glycols are also abused, Common derivatization techniques to form cyc lic ester of ethylene glycol work only for 1,2-diols and cannot deriva tize other glycols like diethylene glycol. The authors describe novel derivatization technique of ethylene glycol (Molecular weight 62) usin g 4-carbethoxyhexafluorobutyryl chloride that produces a distinct prot onated molecular ion peak at m/z 563 in chemical ionization mode, thus aiding in unambiguous confirmation of ethylene glycol. The authors' n ovel derivatization technique is not limited to 1,2-diols and can deri vatize any glycol. It yields less volatile derivatives than any conven tional derivatives and is free from interference from the serum matrix . Moreover, those glycols produce distinctively different mass spectra compared to ethylene glycol, Quantitation of ethylene glycol can be e asily achieved by using 1, 2-butanediol as an internal standard. The a ssay showed a within run and between run precision of 6.7% and 8.2% an d a linearity from 1.1-36.1 mmol/L (70-2,240 mu g/mL) of serum ethylen e glycol concentration.