Page 26 - Microorganism Species Analysis
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LCMS-2020 LCMS-2020
Analysis of Nucleic Acids, Amino Acids, and Aflatoxins
Microorganism Solutions Microorganism Solutions
LC/MS Analysis of Microorganism-Derived Components Data
Liquid chromatography has been widely used for the analysis of microorganism-derived components. However, the UV
detector cannot achieve adequate sensitivity for compounds with almost no UV absorption. Sophisticated investigation of the Analysis of Aflatoxins
separation conditions is often necessary, such as for the analysis of trace levels of components in a mixture. LC/MS uses a
Aflatoxin is a natural, highly carcinogenic toxic Microorganism Species Observation of
variety of methods to ionize the sample components. This method separates these ions in a vacuum according to the
Int. 313.00 (1.22) substance produced by a mould (Aspergillus). This
mass-to-charge ratio (m/z) and detects the ion intensities at high sensitivity. The mass is information unique to the molecule 35000 315.10 (1.00) G2 m/z 331
and directly using this information makes it simple to analyze complex component mixtures. 32500 329.10 (1.00) S/N=557 mould grows on crops such as peanuts and corn.
Observation of
331.10 (1.00)
The Japanese Ministry of Health, Labour and Welfare has set and notified standards and test methods for mycotoxins such 30000 The Japanese Ministry of Health, Labour and
27500 G1 m/z 329 Welfare notified a test method for aflatoxins in 1971.
Microorganism Species
as patulin and aflatoxin produced as secondary metabolites of mould. 25000 S/N=398
The Japanese Food Sanitation Act regulates foods
22500
B2 m/z 315
20000 S/N=296 in which more than 10 ppb aflatoxin is detected.
17500 B1 m/z 313 The aflatoxin test method was upgraded to use
S/N=203
Features of the LCMS-2020 Ultra Fast Liquid Chromatograph Mass Spectrometer 15000 non-toxic reagents on 26 March 2002 and new LC
12500
fluorescence detection and LC/MS methods were
10000
Prominence UFLC offers both speed and separation capacity as well as high accuracy and expandability not
7500 adopted.
available from conventional HPLC. Used with a high-speed, high-accuracy autosampler, it achieves genuine high 5000
throughput. Microorganism Species Identification of
2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 min
Rapid 15 msec positive/negative ion switching time permits high-speed detection (MS measurements) that follows
high-speed LC separation.
Fig. 1 SIM Chromatogram of Aflatoxin Mixture (2.5 ppb each)
Identification of
The newly developed Qarray ion optical system achieves superior sensitivity, reproducibility, and linearity.
Rapid, 15,000 u/sec scanning achieves high ion permeability while maintaining resolution.
Microorganism Species
Analytical Conditions
The LCMS-2020 dramatically enhances long-term stability and ease of maintenance. Column : Imtakt Cadenza CD-C18
Int.
LCMSsolution maximizes analysis performance with a number of comprehensive functions including data 313.00 (1.41) G2 m/z 331 (150 mm L. × 2.0 mm I.D.)
9500 315.10 (1.21) S/N=84 G1 m/z 329 Mobile phase : acetonitrile / methanol / 10 mM ammonium acetate
comparisons, peak integration, and report output. 9000 329.10 (1.08) = 2 / 6 / 15
331.10 (1.00) S/N=60 Flow rate : 0.2 mL/min
8500 B2 m/z 315 B1 m/z 313 Column temp. : 40 °C
8000 S/N=62 S/N=43 Injection volume : 6 µL
7500 Probe voltage : 4.5 kV (ESI-positive mode)
7000 CDL temp. : 300 °C
Nebulizing gas flow : 1.5 L/min
6500
Drying gas pressure : 0.15 MPa Specific Microorganisms Detection of
6000
CDL voltage : 25 V
5500 Qarray DC voltage : Scan mode
5000 Qarray RF voltage : Scan mode
4500 Scan range : m/z 200-400 (1.0 sec/scan)
Detection of
4000 SIM : m/z 331.1, 329.1, 315.1, 313.0 (0.25 sec/ch)
3500
3000
Specific Microorganisms
2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 min
Fig. 2 SIM Chromatogram of Aflatoxin Mixture (0.5 ppb each)
Fig. 1 shows the SIM chromatogram of
LCMS-2020 four aflatoxin components, G2, G1, B2, Components Analysis of Microorganism-Derived
Ultra Fast Liquid Chromatograph Mass Spectrometer Int. Area
B1 (each 2.5 ppb), and Fig. 2 shows the Aflatoxin G2 331.1 17.5e6
Components
SIM chromatogram of 0.5 ppb 1250e3 MW 330 15.0e6
1000e3 12.5e6
concentrations. A satisfactory S/N ratio
750e3 10.0e6
was obtained, even at 0.5 ppb 7500e3
500e3
concentration of each component. 369.0 5000e3
Analysis of Microorganism-Derived
250e3 353.1 389.1 2500e3
The LC/MS test method for aflatoxins 313.3 362.1 r 2 =0.99998
0e3 0e3
conforming to the official analytical 200 250 300 350 m/z 0 25 50 75 Conc
method is introduced here. Int. Area
Aflatoxin G1 329.1 17.5e6
Fig. 3 shows the MS spectra and MW 328
750e3 15.0e6
calibration curves for aflatoxin G2 (600 12.5e6
pg) and aflatoxin G1 (600 pg). The 500e3 10.0e6 Other Applications
7500e3
calibration curves achieve good linearity
250e3 5000e3
with r 2 (coefficient of determination) = 374.1 2500e3
311.0 r 2 =0.99999
0.9999 min. 0e3 0e3
200 250 300 350 m/z 0 25 50 75 Conc
Other Applications
Browser screen Analytical conditions optimization screens
LCMSsolution Ver.5 Fig. 3 MS Spectra and Calibration Curves for Aflatoxin G2 and G1
LCMS-2020 Workstation
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