The overall protocol using the Zic-Hilic stationary phase is very rapid, the only sample pretreatment that was required is a simple dilution step and DEG eluted in less than three minutes
Mass poisoning epidemics have occurred from the ingestion of pharmaceutical preparations containing toxic substances.
When an epidemic of this nature occurs, a rapid and sensitive analytical protocol is required to determine the cause so that the appropriate corrective action can be initiated as rapidly as possible.
As an example, the accidental use of diethylene glycol (DEG) in place of glycerin or propylene glycol has been the cause of several epidemics; a recent case led to 51 deaths in Panama occurred when diethylene glycol was used in an antihistamine/expectorant preparation.
Researchers at the US Centers for Disease Control (CDC) developed an analytical protocol to rapidly detect diethylene glycol in the preparation using a Zic-Hilic column (DB Barr, et al, J Anal Tox 31, 295 (2007)).
In this analytical protocol, DEG was separated from the diluted sample using a Zic-Hilic column (150x2.1mm packed with 5um particles) and a mobile phase consisting of 84.5 % acetonitrile/water (84.5/15.5) modified with 5mM ammonium acetate at a flow rate of 200ul/min.
DEG was identified using a atmospheric pressure chemical ionization mass spectrometer with isotopically labeled DEG as internal standard.
The Zic-Hilic stationary phase used in this work is an extremely versatile phase for HPLC that is said to be superb for the separation of polar compounds.
It employs zwitterionic sulfobetaine groups that are bonded to a silica backbone and has many of the characteristics of a normal phase.
A major advantage of the stationary phase is that a significant aqueous fraction can be employed in the mobile phase, thereby providing for greater solubility of polar analytes and greater sensitivity.
