342 / 658
We confirmed the presence of ranitidine and
metoclopramide through the mass spectra, which are very
similar to that present in the library and the measured
retention times are very similar to the expected (Figure
2). Moreover, some immunoassays are known to give
cross-reactivity between ranitidine and amphetamines. As
a consequence, we established that a false positive was
found by the immunoassay and the ToxSpec Analyzer that
identified the cross-reacting molecule as ranitidine.
Conclusion
The ToxSpec Analyzer was used to screen toxic
compounds and their metabolites in urine based on
LC-MS/MS. This method has been compared with other
classical screening techniques such as HPLC-DAD and
an immunoassay. LC-MS/MS demonstrated more reliable
results than other techniques. In conclusion, the
LC-MS/MS method provides rapid sample preparation,
ease-of-use, sensitivity, specificity and a low cost per
sample analysis, making the ToxSpec Analyzer an
appropriate tool for non-targeted screening in a forensic
toxicology laboratory.
Peak 1
1
2
3
4
5
6
7
8
9
10
11
12
Time (min)
0
20
40
60
80
100
Relative Abundance
6.90
6.88
6.92
8.46
6.86
1.91
8.54
7.10
9.39
1.99
5.45
7.75
6.47
NL: 1.37E2
m/z= 236.60-237.60 F:
ITMS + c ESI w Full
ms2
356.20@cid35.00
[95.00-360.00]
Figure 1. Example ToxID software short report showing ion chromatogram and a compound detected in urine positive for LSD.
Peak
Compound Name
Code
SI
RSI
m/z
Expected RT
Actual RT
Intensity
Library Name
Number
1
OH-LSD
m
756
922
356.20
6.20
6.90
15461
Tox_Library_LXQ