ISO 20636-2018 PDF

Full title and description

Infant formula and adult nutritionals — Determination of vitamin D by liquid chromatography‑mass spectrometry. ISO 20636:2018 specifies a validated LC‑MS/MS method for the quantitative determination of vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) in powdered and liquid infant formula and adult nutritional products.

Abstract

This International Standard defines a test method based on sample saponification, solvent extraction, derivatisation and reversed‑phase liquid chromatography with tandem mass spectrometric detection for the quantitative determination of vitamin D2 and/or vitamin D3 in infant formula and adult nutritionals (powders, ready‑to‑feed liquids and concentrates). Typical application ranges run from about 0.15 µg/100 g (LOQ) to 59 µg/100 g for vitamin D2 and from about 0.25 µg/100 g to 65 µg/100 g for vitamin D3.

General information

• Status: Published (International Standard, confirmed on systematic review).
• Publication date: July 2018 (ISO 20636:2018).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 67.050 (General methods of tests and analysis for food products).
• Edition / version: Edition 1 (2018).
• Number of pages: 23.

Scope

Specifies a laboratory method for the quantitative determination of vitamin D2 and/or vitamin D3 in infant formula and adult nutritional products in both solid (powder) and liquid (ready‑to‑feed and concentrates) matrices. The method covers sample preparation (including alkaline saponification and extraction), derivatisation to enhance ionisation, chromatographic separation and MS/MS detection, and includes guidance on use of isotope labelled internal standards, calibration and performance characteristics within the stated analytical ranges.

Key topics and requirements

• Analytes: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
• Applicable matrices: infant formula powders, ready‑to‑feed liquids and liquid concentrates, and similar adult nutritional products.
• Sample preparation: alkaline saponification and extraction of the lipid fraction to isolate vitamin D prior to analysis.
• Derivatisation: use of PTAD (4‑phenyl‑1,2,4‑triazoline‑3,5‑dione) or equivalent to form adducts that improve MS ionisation and sensitivity.
• Analytical technique: reversed‑phase liquid chromatography coupled to tandem mass spectrometry (LC‑MS/MS) with multiple reaction monitoring (MRM).
• Quantification: use of stable isotope labelled internal standards to correct for extraction, derivatisation and ionisation variability.
• Performance range and limits: LOQ and validated working ranges typically around 0.15 µg/100 g (D2) and 0.25 µg/100 g (D3) up to the tens of µg/100 g; laboratories must verify LOQ/LOD for their setup.
• Validation and quality control: method performance characteristics (repeatability, reproducibility, recovery, uncertainty) and use of appropriate QC samples and calibration procedures.
• Reporting: reporting of results on a specified basis (mass per 100 g or per 100 kcal as required), and statement of measurement uncertainty and method conditions.

Typical use and users

Primary users are commercial and regulatory testing laboratories, infant formula and adult nutritional product manufacturers, quality assurance teams and research laboratories involved in nutrient analysis and product compliance testing. The method is intended for routine analysis, product release testing, regulatory compliance assessment and inter‑laboratory comparison studies.

Related standards

ISO 20636:2018 is part of an ISO series of methods for nutrients in infant formula and adult nutritionals. Closely related standards include ISO 20633 (vitamins A and E), ISO 20634 (vitamin B12), ISO 20635 (vitamin C), ISO 20637 (myo‑inositol), ISO 20638 (nucleotides), ISO 20639 (pantothenic acid) and ISO 23443 (β‑carotene, lycopene and lutein). ISO 20636 is equivalent to AOAC Official Method 2016.05 for vitamin D in infant formula; EN/other compendial HPLC/LC‑MS methods for vitamin D (historic EN methods and AOAC methods) are commonly referenced for comparison and cross‑validation. The Codex standard for infant formula (Codex STAN 72‑1981) provides compositional/regulatory context for nutrient determinations.

Keywords

ISO 20636, vitamin D, cholecalciferol, ergocalciferol, infant formula, adult nutritionals, LC‑MS/MS, PTAD derivatisation, isotope internal standard, saponification, LOQ, analytical method, nutrient analysis.

FAQ

Q: What is this standard?

A: ISO 20636:2018 is an International Standard that specifies a liquid chromatography‑mass spectrometry (LC‑MS/MS) method for the quantitative determination of vitamin D2 and vitamin D3 in infant formula and adult nutritional products.

Q: What does it cover?

A: It covers sample preparation (including saponification and extraction), derivatisation (typically PTAD), chromatographic separation, MS/MS detection, use of stable isotope internal standards, calibration, performance characteristics and reporting within specified analytical ranges for vitamin D2 and D3 in powdered and liquid matrices.

Q: Who typically uses it?

A: Commercial and regulatory testing laboratories, manufacturers of infant formula and adult nutritionals, QA/QC personnel and researchers performing nutrient analysis and product compliance testing.

Q: Is it current or superseded?

A: ISO 20636:2018 was published in July 2018 and underwent the ISO systematic review process; it was confirmed as the current version during the 2023 review. Users should check with their national standards body or ISO for any subsequent revisions after 2023.

Q: Is it part of a series?

A: Yes. ISO 20636 is part of a group of ISO standards addressing analytical methods for vitamins and other nutrients in infant formula and adult nutritionals (examples: ISO 20633, ISO 20634, ISO 20635, ISO 20637, ISO 20638, ISO 20639, ISO 23443) and is also aligned with AOAC methods used for the same purpose.

Q: What are the key keywords?

A: vitamin D, cholecalciferol, ergocalciferol, LC‑MS/MS, PTAD, saponification, infant formula, adult nutritionals, internal standard, LOQ, nutrient testing.