42 / 164
Silliker
Chem, Res. Center Crete, IL – Report of A Validation of LC-MS/MS Method for Folate Analysis
16
in a sample is calculated based on calibration curve. Concentration of each of the
folate compound as ng/mL in a sample is adjusted by substracting the amount of
respective folate compound detected in blank (processed like sample) ran in the
batch. Concentration of each of the folate compound as ng/mL in a sample is
adjusted further by multiplying with corresponding recovery factor.
So estimated folate vitamer concentration in the extract is then multiplied by
dilution volumes (if any) and final volumes of the relevant steps (elution volume
for SPE, 1 mL). Total amount folate vitamer in the extract is then adjusted for the
aliquot of the sample used for extraction. The folate vitamer then calculated as
mcg/100g of the sample or any other desired unit.
Total folate as folic acid is calculated in the samples mcg/100g by multiplying
mcg/100g of the folate compound by the following conversion factors
Folate
Vitamers
Formula
Weight
Multiply
by to
convert to
FA
Example
value
mcg/100g
Value as
FA
mcg/100g
sum of all
folate
compound as
folic acid
FA
441.4
1
100.0
100.0
5-CH3-THF
459.5
0.9606
100.0
96.1
5-CHO-THF
473.4
0.9324
100.0
93.2
5 ,6,7,8-THF
445.4
0.9910
100.0
99.1
5,10-CH=CH-
THF
456.4
0.9671
100.0
96.7
10-CH3-FA
455.4
0.9693
100.0
96.9
10-CHO-FA
469.4
0.9403
100.0
94.0
Total Folate as
FA
Sum as FA
676.1
Reference:
Modification of the AOAC 2011.06
2011.06 (Fol-22) w/SLV
FOR ERP USE ONLY
DO NOT DISTRIBUTE