Page 35 - Clinical-Medical Solution for Clinical Chemistry

Evaluation of an automated LC-MS/MS system for
analyzing hydrophilic blood metabolites

Table 2. Comparison between the manual and automatic methods for
analyzing branched-chain and aromatic amino acids

Pre-treatment Concentration RSD Reference concentration
Product name SD
( M) (%) ( M)
Manual method 210.6 8.19 3.89
L-valine 215
Automatic method 200.2 6.65 3.32
Manual method 132.8 7.20 5.42
L-leucine 127
Automatic method 126.4 4.30 3.40
Manual method 65.6 3.38 5.15
L-isoleucine 69
Automatic method 66.8 2.81 4.22
Manual method 71.8 2.37 3.30
L-tyrosine 67
Automatic method 67.8 2.58 3.80
Manual method 54.6 1.81 3.32
L-phenylalanine 55
Automatic method 54.5 1.97 3.61
Manual method 3.24 0.048 1.47
Fischer ratio 3.4
Automatic method 3.22 0.033 1.03

Table 3. Comparison between the measurement stability of manual
and automatic methods
The number of detected metabolites
Method Manual method Automatic method
Total 45 46
0%<RSD%£20% 33 (73.3%) 40 (87.0%)
20%<RSD%£50% 11 (24.4%) 6 (13.0%)
50%<RSD% 1 (2.2%) 0 (0%)

To the best of our knowledge, this is the rst study in CLAM-2000-based procedure that remain to be
which the CLAM-2000 was utilized for metabolomics. evaluated. For example, the extracted solutions are
The CLAM-2000 is a fully automatic pre-treatment device directly transferred into an autosampler, but it might be
for LC/MS, and it can be connected online to an LC/MS better to dilute the extracted solutions with H 2 O to
system. Therefore, metabolome analysis using the reduce the percentage of organic solvent in the solution
CLAM-2000 might be suitable for measuring larger because a higher percentage might lead to column
numbers of serum/plasma samples, because CLAM-2000 ooding and poor chromatography. In addition, removal
has no manual step leading to the decreased accident of lipids from the extracted solutions may be also needed
error by hand working, and moreover CLAM-2000 for the stable measurement. If these problems could be
automatically can do the metabolite extraction and the resolved, metabolome analysis using the CLAM-2000
following measurement of 60 serum/plasma samples in could become more practical.
one batch. However, there are some issues related to our

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