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identification. The method was applied in forensic casework. Dams et al. 206
developed a LC/APCI/MS/MS (ion trap) screening method for selected
drugs of abuse (opiate agonists, cocaine, and metabolites) in plasma, saliva,
and urine. The samples were only subjected to acetonitrile precipitation
before analysis. No ion suppression was observed for the compounds
207
involved. In the study of Nordgren and Beck, urine samples were 1:10
diluted with water and directly injected into LC/APCI/MS/MS. A small
library of 24 drugs of abuse was established. The procedure was applied in
routine casework; among 529 analyzed samples, in 32 cases various drugs
were found, mainly psychoactive phenethylamines. Direct analysis of urine
was applied also by Fitzgerald et al., 208 who modified REMEDi HPLC ana-
lyzer for use with ion trap MS. A small library of 17 drugs belonging to
different classes was established. Urine samples were extracted on-line as
for HPLC/DAD analysis.

2.7 Perspectives and Future Trends

Existing needs and observed trends of development allow predicting the main
pathways of progress in LC/MS applied for forensic toxicology. This progress
may be divided into following categories:

• Sample preparation for LC/MS: The problems caused by coeluting
matrix compounds (ionization suppression, spectra overlapping)
have been well recognized. Therefore, more stress will be put on the
development of fast and efficient isolation techniques.
• HPLC separation: A trend to shortening of analysis time will be ob-
served, similar to that in clinical toxicology. This may be achieved
either through introduction of columns assuring faster and more
efficient separation (short, fine-grain or monolithic columns),
through application of fast elution (fast gradient, high percentage of
organic solvent in mobile phase, high flow rate), or by flow switching
of eluent flow during separation process.
• Application area: LC/MS will cover practically the whole spectrum of
compounds of toxicological relevance. The use of LC/MS as a tool
for general screening procedures will be common, and the libraries
of mass spectra will be available with any purchased instrument. Most
probable will be combined use of in-source CID for preliminary
screening with consecutive MS/MS confirmation.
• Technical aspects: Detection part of LC/MS, i.e., the mass spectrometer
itself, will became smaller without compromising the quality. Bench-
top, tandem mass spectrometers at affordable prices already have

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