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Silliker
Chem, Res. Center Crete, IL – Report of A Validation of LC-MS/MS Method for Folate Analysis
23
Figure 2
:
Calibration Curve of different folate compounds (Dionex 3000 Ultmate HPLC and
5500 API MS detector). The color scheme for the calibration curve of different folate
compounds is as the following
.
Folate (295) ______,
5-CH3-THF (313)_______,
5-CHO-THF
(327)_______,
THF (299) _____,
10-CHO-FA (295)_________,
10-CH3-FA (309) ______.
CH=THF (282) _______. Conc
Calibration Values:
The calibration values based on the above calibration curve for different folate compounds are listed in
the following Table.
Table 15: Evaluation of Response Linearity against concentration of six target folate compounds
the values of linear regression
Folate
Compound
Transition
Slope
Intercept
r2
weighing
Calibration
Line Color
Folic Acid
295
0.02807 +0.00269 0.9996
1/x
Navy Blue
5-CH3-THF
313
0.02453 +0.01463 0.9931
1/x
Purple
5-CHO-THF
327
0.02746 +0.01105 0.9922
1/x
Red
THF
299
0.01553 -0.01530
0.9992
1/x
Orange
CH=CH-THF
282
0.1050 +0.00211 0.9965
1/x
Sky Blue
10-CH3-FA
309
0.03783 -0.01387
0.9979
1/x
Light Green
10-CHO-FA
295
0.04435 +0.00650 0.9996
1/x
Dark Green
Effect of Methanol concentration in the injection solvent
The initial calibration work and the injection solvent for LC-MS analysis of the analytes used in the
AOAC proposed method contains methanol at 20% in a mixture with 80% of 1% acetic acid solution
along with 1% ascorbic acid (20:80:1 v/v/w). In the subsequent work we found a way to make the
method a little bit less time consuming and labor intensive and most important to improve analyte
Folate Compound
Concentration (ppb)
2011.06 (Fol-22) w/SLV
FOR ERP USE ONLY
DO NOT DISTRIBUTE