Overview
ISO/TS 21310:2020 - Traditional Chinese medicine - Microscopic examination of medicinal herbs - specifies standardized methods for the microscopic analysis of plant-derived medicinal materials used in traditional Chinese medicine (TCM). The technical specification describes required equipment, sampling amounts, sample preparation (sections and powders), mounting/swelling agents, observation procedures and reporting. It applies to Chinese materia medica (whole medicinal materials) and decoction pieces derived from plants, but excludes animal- or mineral-derived materials.
Key topics and technical requirements
- Scope and definitions: Clarifies terms such as microscopic examination, slide, cover glass and micrometer; prepared in line with ISO/TC 249 terminology.
- Sampling: Guidance on representative sample sizes - small/powdered (50–250 g) and large/whole (250–500 g) - and preservation in airtight containers when needed.
- Apparatus: Use of optical microscopes or slide scanners, micrometers (optical or software), imaging devices (digital cameras), slides, cover glasses and botanical dissecting tools (tweezers, microtome, razor).
- Preparation methods:
- Cross-section and longitudinal-section slides (cutting to 10–20 µm; optional paraffin embedding).
- Powder slides (swelling in agents for ≥10 minutes and uniform smearing).
- Mounting and swelling agents (e.g., glycerine/water 1:1 or glycerine/95% ethanol/water 1:1:1).
- Annex A contains informative methods: moisturizing, fixation (ethanol, formalin, F.A.A., Craf III), maceration (KOH, chromic‑nitric, potassium chlorate), sectioning (free-hand, paraffin embedding, frozen/cryosection) and staining.
- Observation: Recommended observation order for whole and powdered samples (outer/inner portions, characteristic components, cell contents); includes histochemical detection procedures (e.g., phloroglucinol test for lignified walls).
- Test report requirements: Must include sample identification, sampling method, reference to ISO/TS 21310:2020, test methods and results, optional operating details, anomalies and test date.
Applications and intended users
- Quality control laboratories in herbal medicine manufacturers and suppliers
- Regulatory and pharmacopoeial testing bodies evaluating botanical identity and purity
- Research laboratories conducting anatomical and histochemical studies of medicinal herbs
- Educational institutions teaching pharmacognosy and TCM materia medica
ISO/TS 21310:2020 helps ensure consistent, reproducible microscopic identification of plant-based TCM materials, supporting authenticity checks, adulteration detection and quality assurance.
Related standards
- ISO/TC 249 (Traditional Chinese medicine) - responsible technical committee
- Cited terminology sources: ISO 17639:2003 and ISO 10934-1:2002 (for microscopy terms)
Keywords: ISO/TS 21310:2020, traditional Chinese medicine, microscopic examination, medicinal herbs, Chinese materia medica, decoction pieces, sample preparation, microscopy, microtome, paraffin embedding, powder slides, histochemical detection.
