Introduction

Gas chromatography/mass spectrometry (GC/MS) is the technique of choice for the

quantitative determination of semivolatile organic compounds (SVOCs). Matrices can

vary greatly from air and water samples to soils and solid waste extracts. As such, the

effect of matrices on the GC/MS system can vary greatly.

Of particular concern are matrices that may detrimentally affect the suitability of the

GC/MS system for analysis. For example, samples with high particulate content,

involatile material, or reactive chemicals may cause irreversible changes to the

GC/MS system.

Inert inlet liners packed with glass wool are a good choice to prevent column

contamination. In addition, the use of a deactivated fused silica precolumn has also

demonstrated utility in column protection. However, these precolumns can be difﬁcult

to install and maintain in traditional GCs.

The AgilentIntuvo 9000 GC incorporates an Intuvo Guard Chip that provides column

protection analogous to a deactivated fused silica precolumn. However, unlike fused

silica precolumns, the Intuvo Guard Chip is easy to install and maintain.

To ensure that the GC/MS has not become contaminated with matrices, periodic

analysis of a control sample is good practice. For example, the United States

Environmental Protection Agency (USEPA) method 8270D speciﬁes the use of a

control standard to test for inertness and column performance every 12 hours

This Application Note demonstrates that the Intuvo Guard Chip provides protection

from repetitive injections of soil extracts by maintaining system suitability

speciﬁcations as established in USEPA 8270D for the quantitative analysis of SVOCs

in environmental matrices.

ANALYSIS OF SEMIVOLATILES

INTUVO GUARDCHIP PROTECTION

Technology Advantage: AgilentIntuvo 9000 GC with

Agilent5977 MSD

For more information, visit:

www.agilent.com/chem/intuvo

Information, descriptions and speciﬁcations in this

publication are subject to change without notice.

Published in USA, September 1, 2016

5991-7182EN

Instrumentation

• AgilentIntuvo 9000 GC

• Agilent5977 MSD

• Agilent Intuvo DB-5ms UI,

30 m × 0.25 mm, 0.5µm column

Sample Preparation

• A standard mixture of DFTPP,

4,4’-DDT, benzidine, and

pentachlorophenol

• Composite soil extract was supplied

by an environmental contract lab

Results and Discussion

Figure1 shows an image of the soil

extract used in the study, and an inlet

liner after 20 matrix injections. The

opaque extract leaves a noticeable

residue in the inlet liner after

20injections.

Figure2 shows the tailing factor for

pentachlorophenol and benzidine

measured at intervals of 20 matrix

injections, over the course of 400 total

injections. Tailing factor measurements

were made after replacement of the

contaminated liner. According to 8270D,

the tailing factor for these probes cannot

exceed 2 at 10% peak height.

In Figure2, the tailing factor for

benzidine increases from 1.3 after

160 matrix injections to 1.8 after

240injections. The increase in the

tailing factor for benzidine indicates that

the system is sustaining some acidic

activity that cannot be attributed to

matrix contamination of the liner.

Figure 1. Soil extract and liner residue after 20 injections.

Figure 2. Tailing factor reduced after Intuvo Guard Chip replacement.

Before Intuvo Guard Chip

replacement (TF = 1.8 )

After Intuvo Guard Chip

replacement

(TF = 1.2)

Tailing factor limit

0.0

0.5

1.0

1.5

2.0

2.5

050100 150200 250 300350 40

Tailing factor

Number of matrix injections

Pentachlorophenol

Benzidine

Replacement of the Intuvo Guard Chip after 240matrix injections reduces the

benzidine tailing factor from 1.8 to 1.2. This suggests that some matrix penetrated

the liner, and the Intuvo Guard Chip prevented downstream contaminating. System

performance was restored after replacement of the Intuvo Guard Chip.

Conclusion

This study shows that replacement of the Intuvo Guard Chip can restore system

performance after injection of a heavy soil extract. For more detailed information and

methodology, refer to Application Note 5991-7256EN

References

1. Semivolatile Organic Compounds by GC/MS, U.S. Environmental Protection

Agency, Method 8270D, Revision 4, February 2007.

2. The analysis of semivolatile organic compounds using the Agilent Intuvo 9000

Gas Chromatograph, AgilentTechnologies Application Note, publication number

5991-7256EN.