PKKK/300/UP/049 Screening of Diethylene Glycol in Toothpaste Preparations using GCMS

Equipment/ Materials

Hewlett Packard Gas Chromatograph Mass Detector

Ethanol

25mL volumetric flask

50mL volumetric flask

Diethylene Glycol from Sigma no.D.3381 (Reference Standard)

Chromatographic Parameters

◼ Column : J & W DB – 17 MS, 30m x 250 µm x 0.25 µm

◼ Oven temperature:

◼ Injector temp : 250°C

Aux temp : 280°C

MS temp : 230°C

Quad. temp : 150°C

◼ Mode : Split

◼ Split Ratio : 10 : 01

◼ Column Flow : 1.4 mL/min

◼ Injection volume : 1 μL

Test Method

Reference Standard Preparation

Pippette accurately 20µL of the Reference Standard (using micropipette) and make up to 50mL with Ethanol. Further dilute the solution by taking 4mL and make up to 50mL with Ethanol. Filter the solution before injecting into the GCMS.

Sample Preparation

Measurement

Results

Compare the retention time in the chromatogram and mass in the mass spectrum obtained from the sample with that of the Diethylene Glycol standard.

The identity test is positive if the retention time of the sample is identical to that obtained from the standard chromatogram and the mass (m/z) of the substance matching the mass (m/z) of the standard.

If the sample positive with Diethylene Glycol, further steps is carried out where by an equal amount of standard solution and sample solution was mixed and injected into the GCMS (spiking sample & standard).