Total Folate in Infant Formula and Adult Nutritionals by Trienzyme Extraction and LC-MS/MS Quantitation: A Multilaboratory Testing Study, Final Action 2011.06

Abstract

: The need for an updated reference method for folate was identified as a priority by the AOAC's Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) in 2011. An Expert Review Panel (ERP) found AOAC 2011.06 suitable for the purpose and approved it as a First Action. : To determine the repeatability and reproducibility of Method 2011.06: Total Folate in Infant Formula and Adult Nutritionals by Trienzyme Extraction and LC-MS/MS Quantitation. A multilaboratory collaborative study was conducted. Eleven laboratories located in five countries participated and completed analysis of all multilaboratory testing (MLT) samples. The study was divided into two parts. In the first part, the laboratories analyzed two practice samples (blindly coded) using the updated folate Method 2011.06. The laboratories providing results within the expected range qualified for part two, in which they analyzed 11 MLT samples in blind duplicates. The results were compared with the Standard Method Performance Requirements (SMPR 2011.006) established for folate. The precision results met the requirements stated in the SMPR for all of the samples. Repeatability and reproducibility relative standard deviations ranged from 3.5 to 6.6 and from 9.0 to 15.7%, respectively. Horwitz ratio values for all of the samples were well below 2 (0.61-1.06). The ERP determined that the method performance met the SMPR requirements in September 2017 after reviewing the presented MLT data. The ERP recommended the method for Final Action status.

Quantification of folate in food using deconjugase of plant origin combined with LC-MS/MS: A method comparison of a large and diverse sample set

“…During the analyses by the PE-LC-MS/MS method, the consistency of the folate level was checked by analyzing a certified reference material NIST 1869 Infant/Adult Nutritional Formula. The total folate content expressed as folic acid equivalent was 232 ± 12 µg/100 g (n=5), which was in accordance with previous study (Bhandari et al, 2018). Moreover, in-house reference material (freeze-dried white cabbage) was analyzed on each day of analyses.…”

“…The natural variations between different food varieties, and also the differences in the methods used for folate determination, have led to big discrepancies in results (Delchier et al, 2016). Recently, a UPLC-MS/MS method has been approved as an AOAC-method for determination of 5-CH 3 -H 4 folate, 5-HCO-H 4 folate, and PteGlu as the total folate content expressed as PteGlu equivalent in the two food matrices, infant formula and adult nutritionals, by the trienzyme treatment including rat plasma as the deconjugase enzyme (Bhandari, Ming, & Szpylka, 2018; Journal Pre-proof J o u r n a l P r e -p r o o f 5 Szpylka, De Vries, Cheney, & House, 2012). Even though tri-enzyme extraction has been proposed as a method of choice, Ringling and Rychlik (2017a) have found no differences between tri-enzyme extraction and single-enzyme extraction, using a combination of chicken pancreas and rat serum as folate hydrolases.…”

Collaborative study: Quantification of total folate in food using an efficient single-enzyme extraction combined with LC-MS/MS

“…The content varied from 8.7 to 248 μg/100 g, with a repeatability of 4.4% -10%, and reproducibility of 9.0% -28% (Table 3). The repeatability was similar to that found in the single-laboratory validation study for foods and obtained for NIST 1869 in a multi-laboratory study on infant formula and adult/pediatric nutritionals (Bhandari, Ming, & Szpylka, 2018;Ložnjak et al, 2019).…”

The use of a plant enzyme for rapid and sensitive analysis of naturally-occurring folates in food by liquid chromatography-tandem mass spectrometry

“…Although both of these detectors are highly sensitive, the better selectivity, the unaltered capacity of detection with the time and easier handling with the system makes LC-MS/MS a system of choice for folate analysis. Recently, a LC-MS/MS method for quantification of PteGlu, 5-CH3-H4folate and 5-HCO-H4folate has been successfully tested in infant formula and adult nutritionals by the use of tri-enzyme extraction [43]. The aim of this study was to develop a rapid, sensitive and reproducible LC-MS/MS method for folate analysis in foodstuffs such as: dairy products, cereals, legumes, fruit, vegetables, offal and meat, using a GGH of plant origin (Arabidopsis thaliana).…”