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Thermo Scientific Poster Note
•
PN64229-MSACL-EN 0814S
Resu
Over 96
(Analyte
Formula
compari
Analyte Precursor
(m/z)
Product
(m/z)
Analyte Precursor
(m/z)
Product
(m/z)
Cit
232.10
113.10
C0
218.25
85.00
Cit IS
234.10
115.10
C0 IS
227.25
85.00
Met
206.15
104.10
C8
344.25
85.00
Met IS
209.20
107.10
C8 IS
347.25
85.00
Orn
189.20
70.20
C14
428.35
85.00
Orn IS
191.20
72.20
C14:1
426.35
85.00
Phe
222.10
120.10
C14 IS
437.35
85.00
Phe IS
228.20
125.90
C16
456.35
85.00
Tyr
238.10
136.10
C16 IS
459.35
85.00
Tyr IS
244.10
142.10
Meta Calculation Software
A new meta calculation software, iRC PRO (2Next srl, Prato, Italy)
was used for offline automated calculation of raw data files
generated from Tandem MS in SRM scanning mode. This software
is designed specifically for Thermo Scientific™ TSQ Tandem MS.
This beta version of software is developed for an automatic
calculation of mass ion ratio and user defined formulas.
Data Analysis
Manual Calculation:
Manual calculation was performed by creating
a processing method to extract chromatograms and calculate peak
areas for each analyte and IS using Thermo
Scientific™Xcalibur™
software.
Peak areas were exported in Excel (Microsoft Co.) format and copied
and pasted into an Excel worksheet setup to calculate analyte
TABLE 1. SRMs Monitored for Amino Acids and Acylcaritines
Ty
Anal
Peak
Anal
Concen
For
Concen
(User D
For
Peak
TABLE
Methods
Sample Preparation
Samples were extracted from dried blood spot cards; the internal
standards were added during the extraction procedure and extracted
samples were derivatized prior to injection onto an LC-Tandem MS
system. Quality Control (QC) samples were added to the batch.
Liquid Chromatography Tandem Mass Spectrometry
The flow injection was conducted using a LC with open-tube providing
an automated sample introduction to a Tandem MS (Thermo Fisher
Scientific, San Jose, CA) without chromatographic separation. The
Tandem MS used selected reaction monitoring (SRM) scanning for the
detection of amino acids and acylcarnitines. Transitions used in this
study are listed in Table 1.