Overview
ISO/TS 13126:2023 - Traditional Chinese medicine - Determination of ochratoxin A in natural products by liquid chromatography coupled with fluorescence detector (LC‑FLD) - specifies a standardized laboratory method for detecting ochratoxin A (OTA) in natural products, including raw materials and manufactured decoction pieces derived from plants and animals. The technical specification targets quality control across harvesting, transportation, storage and domestic/foreign trade of traditional Chinese medicine (TCM) and other natural-product supply chains.
Key topics and technical requirements
- Scope: Applicable to raw materials and manufactured products (decoction pieces) from plant and animal sources; suitable for samples in production, storage and trade.
- Analytical approach: Liquid chromatography with fluorescence detection (LC‑FLD / HPLC‑FLD) is the recommended method for OTA due to sensitivity, accuracy and cost-effectiveness. LC‑MS/MS is noted as an alternative technique for multi‑mycotoxin analysis.
- Sample preparation: Crush and sieve samples; extract 25.0 g powder with 4.0 g NaCl in 85 mL methanol:water (80:20), homogenize (>11 000 rpm, 2 min), centrifuge (4 000 rpm, 10 min), then immunoaffinity column clean‑up, elute with methanol and filter (0.22 µm).
- LC‑FLD conditions: Use octadecylsilyl (C18) column; mobile phase acetonitrile–glacial acetic acid–water (isocratic); flow rate 1.0 mL/min; detector excitation λex = 333 nm and emission λem = 477 nm; chromatographic resolution between adjacent peaks > 1.5.
- Calibration and quantification: Stock and working solutions covering 0.1–100 ng/mL; inject 25 µL for calibration curves plotting peak area vs concentration.
- Sampling & storage: Batch sample minima (general materials ≥100 g, powdered ≥25 g, precious materials ≥5 g); store prepared samples in the dark at 4 °C and document chain of custody.
- Validation: Method validated for liquorice extract/root; other matrices require method validation before routine use.
Applications and users
ISO/TS 13126:2023 is practical for:
- Analytical and quality control laboratories testing OTA in TCM and natural products
- TCM manufacturers and raw material suppliers implementing mycotoxin monitoring
- Regulatory bodies and inspection agencies assessing compliance with maximum residue limits (MRLs)
- Import/export quality control for domestic and international trade
- Research groups validating analytical methods for herbal matrices
Benefits include harmonized test procedures, reproducible results for OTA monitoring, and support for consumer safety and trade conformity.
Related standards
- Annex A lists referenced national and regional analytical methods (e.g., Chinese Pharmacopoeia, GB standards, AOAC, European and British Pharmacopoeias).
- Annex C summarizes referenced MRLs used by different jurisdictions.
- LC‑MS/MS methods are referenced as complementary techniques for multi‑mycotoxin analysis.
Keywords: ISO/TS 13126:2023, ochratoxin A, OTA, LC‑FLD, HPLC‑FLD, traditional Chinese medicine, natural products, immunoaffinity column, mycotoxin testing, method validation, MRLs.