ISO/NP TS 26598

Traditional Chinese medicine — Determination of tar pigments in raw herbal medicine

Scope

This document specifies a screening method for the determination of tar pigments in raw herbal medicine where such adulteration is relevant. It encompasses the identification and extraction processes for synthetic dyes that may be present in herbal materials using Thin Layer Chromatography (TLC) as a preliminary screening test. This document includes detailed procedures for sample preparation to ensure consistency and reliability. A confirmation method using High Performance Liquid Chromatography (HPLC) is provided in Annex A for cases requiring quantitative analysis or verification of positive screening results. This document is applicable to the herbal medicines listed in the Introduction and to any other herbal medicines for which tar pigment contamination has been identified as a quality concern.