SPME App Note 13 Page 1

Screening Packaging
Materials with
Automated SPME
and GC/MS

Varian Application Note

Number 13

Zelda Penton
Varian Chromatography Systems

Key Words:

SPME, 8200CX, Polymers, Saturn

Solid phase microextraction (SPME) was used to compare various packaging materials to assess their suitability
for storing and shipping analytical materials. In a previous publication (SPME Application Note #7), polymeric
beads that had been subjected to various heat treatments were compared; in this note, finished sheets were
examined. The various materials showed specific repeatable contamination patterns. The technique was very
simple—approximately 1-cm

2

of the various samples were placed into 2-mL screw cap vials and the air in the

vials was sampled at ambient temperature.

0 5 10 15 20
Retention time (min)

C

B

A

Empty vial

2

1

Figure 1: Total ion chromatograms of air sampled with a SPME fiber from a blank vial and vials
containing three different packaging materials. Peaks 1 and 2 were tentatively identified as butylated
hydroxytoluene and 2,6-bis (1,1-dimethylethyl)-4-ethylphenol.

varian

SPME App Note 13 Page 2

Instrumentation and Conditions

Instrument:

Varian Saturn 2000 GCMS equipped with an automated SPME III system.

Column:

30 m x 0.25 mm coated with 0.50-µm Supelcowax 10

TM

, 50°C, 1 minute, 10°C/min to 210°, hold 8 min.

Carrier gas: helium, 41 cm/s at 60°C.

Injector:

SPI with SPME insert at 210°C, isothermal.

Ion trap:

Electron impact ionization mode, mass range 50-250 m/z, ion trap temperature, 200°C.

Automated
SPME
Conditions:

Fibers (Supelco, Inc.) were coated with 100-µm Polydimethylsiloxane.
Headspace sampling without agitation in 2-mL vials, 30 minutes absorption, 2 minutes desorption, one
sampling per vial.

Samples:

Three different packaging materials.

Results and Discussion

The samples were cut into one-cm squares and placed in the vials (one piece per vial). Samples were run in
duplicate, with an empty vial at the beginning and end of the series. The total ion chromatograms were inspected
at comparable attenuation. Figure 1 clearly shows the differences in the packaging materials. Note that
duplicates of the same sample were virtually identical (Figure 2). The method is not quantitative, as one would
expect the quantities of the various compounds released from the packaging material to be proportional to the
surface area, but if similar-sized pieces of the materials are placed in the sampling vials, the relative cleanliness
of the different samples becomes obvious.

Figure 2: Total ion chromatograms of two samples of packaging material “B”.

Conclusions

SPME is a very simple and effective technique for rapidly evaluating the cleanliness of packaging materials.
A simple GC-FID system may be used for fingerprinting, or if identification of the contaminants is required,
GC/MS should be utilized.