ISO/FDIS 25187

• Abstract:

  This document specifies the minimum requirements of robust the thin layer chromatography (TLC) identification methods applicable for traditional Chinese medicine. It covers the normative references, terms and definitions, apparatus, experimental procedure, evaluation and documentation, and training. This document is applicable to medicinal herbs, preparations, and other natural produces used in traditional Chinese medicine worldwide.

• Status: Not Published
• ICS: 11.120.10 - Medicaments
• Technical Committee: ISO/TC 249 - Traditional Chinese medicine
• Drafting Committee: ISO/TC 249/WG 2 - Quality and safety of manufactured TCM products
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 08-Sep-2026
• Completion Date: 08-Sep-2026

Overview

ISO/FDIS 25187: Traditional Chinese Medicine - Requirements for Thin-Layer Chromatography (TLC) Identification Methods establishes the minimum requirements for robust thin-layer chromatography (TLC), including high-performance TLC (HPTLC), for the identification of medicinal herbs and natural products used in traditional Chinese medicine (TCM). This international standard ensures a harmonized approach to the identification process, supporting global quality control, regulatory compliance, and the integrity of natural products in TCM practice.

ISO/FDIS 25187 covers fundamental topics such as equipment specifications, experimental procedures, evaluation methods, documentation, and required training. The standard is applicable to medicinal herbs, preparations, extracts, oils, fats, and other natural products, enhancing confidence in the reliability and repeatability of TLC analysis for TCM worldwide.

Key Topics

• Minimum Requirements for TLC & HPTLC: Provides guidance on robust methods for TLC identification of TCM products, enabling consistent quality control across various settings.
• Apparatus and Materials: Outlines specifications for TLC plates, application devices, chromatographic chambers, derivatization and detection devices, ensuring optimal separation and visualization.
• Sample Preparation and Analysis: Details best practices in sample application, development (vertical and horizontal), derivatization, and detection-critical steps for accurate identification.
• Evaluation and Documentation: Establishes requirements for comparing chromatograms, documenting test conditions, handling anomalies, and ensuring data traceability.
• Training: Highlights the importance of operator competency in producing reliable results and maintaining the integrity of TCM identification processes.
• Annexed Examples and Reference Values: Provides in-depth procedural case studies (e.g., Panax ginseng and Fufang Danshen Tablet) and comparative tables summarizing requirements of leading pharmacopoeias.

Applications

ISO/FDIS 25187 is highly valuable in sectors where accurate identification and quality assurance of traditional Chinese medicinal products are essential. Practical applications include:

• Pharmaceutical and Herbal Industry: Ensures the authenticity and purity of raw materials, finished herbal products, and TCM preparations, supporting regulatory submissions and market access worldwide.
• Quality Control Laboratories: Provides a standardized procedure to assess and verify the identity of medicinal herbs and natural extracts using TLC or HPTLC, facilitating reliable comparison with reference substances.
• Research and Development: Supports robust, reproducible testing methodologies for the analysis and identification of herbal compounds in scientific research.
• Pharmacopeial and Regulatory Compliance: Assists manufacturers in adhering to international norms for herbal product identification, aligning with requirements of various national and regional pharmacopoeias.
• Education and Training: Serves as a benchmark for training laboratory personnel in best practices for chromatographic analysis specific to TCM.

Related Standards

For comprehensive implementation and harmonization, ISO/FDIS 25187 should be considered alongside the following key standards and references:

• ISO 23723:2021 - Traditional Chinese Medicine - General requirements for herbal raw material and materia medica
• ISO 19609-2:2021 - Traditional Chinese Medicine - Quality and safety of raw materials and finished products made with raw materials - Part 2: Identity testing of constituents of herbal origin
• ISO 4791-1:1985 - Laboratory apparatus - Vocabulary relating to apparatus made essentially from glass, porcelain, or vitreous silica
• World Health Organization (WHO): Quality control methods for herbal materials (2011)
• Chinese, Japanese, Korean, European, and U.S. Pharmacopoeias: For regional TLC requirements, sample preparation, and identification benchmarks

Leveraging ISO/FDIS 25187 supports the trust and traceability of TCM products, streamlines international trade, and fortifies public safety through scientifically validated identification practices.

Keywords: thin-layer chromatography, TLC, high-performance TLC, HPTLC, traditional Chinese medicine, TCM, ISO standard, medicinal herbs identification, quality control, natural products, herbal authentication.

DRAFT
International
Standard
ISO/DIS 25187
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Minimum requirements for
Voting begins on:
robust TLC identification methods
2025-09-01
applicable for medicinal herbs and
Voting terminates on:
natural products
2025-11-24
ICS: 11.120.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
This document has not been edited by the ISO Central Secretariat.
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 25187:2025(en)
DRAFT
ISO/DIS 25187:2025(en)
International
Standard
ISO/DIS 25187
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Minimum requirements for
Voting begins on:
robust TLC identification methods
applicable for medicinal herbs and
Voting terminates on:
natural products
ICS: 11.120.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
This document has not been edited by the ISO Central Secretariat. BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
Phone: [phone]
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 25187:2025(en)
ii
ISO/DIS 25187:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 2
4.1 Plate .2
4.2 Application device .2
4.3 Chromatographic chamber .2
4.4 Derivatization device .3
4.5 Detection device .3
5 Procedure for TLC analysis. 3
5.1 Storage and pretreatment of TLC plate .3
5.2 Sample Application .3
5.3 Development .4
5.3.1 Vertical development .4
5.3.2 Horizontal development .4
5.4 Derivatization . .4
5.5 Detection .5
6 Evaluation . 5
7 Documentation . 5
Annex A (informative) TLC identification of Panax ginseng root and rhizome . 7
Annex B (informative) TLC identification of Fufang Danshen Tablet . 9
Annex C (informative) Reference values of TLC method in different pharmacopoeias .11
Bibliography .13

iii
ISO/DIS 25187:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 249, Traditional medicine, Subcommittee SC 1,
Traditional Chinese medicine.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/DIS 25187:2025(en)
Introduction
Thin-layer chromatography (TLC) is one of the most widely employed techniques in planar chromatography.
It is a separation technology that samples are separated by migration of solutes in the mobile phase
by utilizing mechanisms such as adsorption, partition, ion-exchange or combinations thereof, and the
separated components are subsequently inspected under ultraviolet or visible light, either prior to or after
derivatization with a chromogenic reagent. TLC exhibits several characteristics: 1) Intuitive results. The
analysis results are presented in the form of images, making them more intuitive and easier to recognize
and remember. 2) Efficiency. The analysis time is relatively short, allowing multiple samples to be separated
simultaneously, thereby facilitating convenient comparisons among them. 3) flexibility. For each of the steps—
sample application, chromatogram development, visualization, detection, documentation, and evaluation—
numerous parameters can be selected freely. 4) Convenient derivatization. The post-chromatographic
derivatization process is straightforward, enabling muti-dimensional chemical and bioactivity analyses to
be conducted following separation. The advantages of high throughput, flexibility and image visualization
render TLC a valuable tool for qualitative identification of botanical drugs across various pharmacopoeias,
including Chinese Pharmacopoeia, Japanese Pharmacopoeia, Korean Pharmacopoeia, British Pharmacopoeia,
European Pharmacopoeia, American Herbal Pharmacopoeia, as well as ISO international standards.
However, TLC is multi-step technique and many of its operational processes occur in an open environment.
Consequently, factors such as the quality of stationary phase, environmental conditions (including
temperature and humidity), and level of operational experience can significantly influence the results when
compared to other analytical technologies. Therefore, it is essential to standardize and unify certain key
parameters to ensure the reliability of results without compromising the technique’s flexibility or increasing
analytical costs.
Several national pharmacopoeias have established specific requirements for TLC analysis; however,
discrepancies in key parameters among these pharmacopoeias can adversely affect the accuracy of results.
To date, there is no standard operating procedure for TLC analytical method in ISO standards. Therefore,
establishing minimum requirements for a harmonized TLC method is necessary for enhance its applicability
and ensure consistent repeatability across various applications.
To facilitate understanding of the clauses and requirements of this standard, Annex A and Annex B provide
two examples: one representing medicinal herbs and the other representing preparation, along with specific
parameter information and result descriptions for reference.

v
DRAFT International Standard ISO/DIS 25187:2025(en)
Traditional Chinese medicine — Minimum requirements for
robust TLC identification methods applicable for medicinal
herbs and natural products
1 Scope
This document specifies the minimum requirements of thin layer chromatography (TLC) identification
methods applicable for traditional Chinese medicine. This document is applicable to medicinal herbs,
preparations, oils, fats, extractives, and other natural produces used in traditional Chinese medicine
worldwide.
2 Normative references
There is no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
Thin-layer chromatography
TLC
technique in analytical chemistry used to separate, identify and quantify each component in a mixture via a
thin-layer consisting of a stationary phase
[SOURCE: ISO 4791-1:1985, 3.02.11, modified]
Note 1 to entry: TLC plate can be of various types used for thin layer chromatography.
Note 2 to entry: When using silica gel as the stationary phase, a TLC plate refers to a plate with silica gel particles sized
between 5 µm to 40 µm, with an average particle size of 10 µm to 15 µm and a thickness of 250 µm.
Note 3 to entry: High-performance thin layer chromatography (HPTLC) refers to a high-performance analytical
technique. When using silica gel as the stationary phase, an HPTLC plate has silica gel particles sized between 2 µm to
10 µm, with an average particle size of 3 µm to 7 µm and a thickness of 200 µm.
3.2
certified reference material
reference material accompanied by a certificate, one or more of whose property values are certified by a
technically valid procedure, accompanied by or traceable to a certificate or other documentation which is
issued by a certifying body
[SOURCE: ISO Guide 30, 2.1.2, modified]
Note 1 to entry: reference material can be one or more reference substances (or standards) or other certified reference
materials, such as the reference drug and the reference extractive.

ISO/DIS 25187:2025(en)
Note 2 to entry: reference solution is prepared by dissolving reference material in a solvent or obtained by other
specified method, correspondingly, the solutions may also be termed standard solution, reference drug solution, or
reference extractive (extract) solution.
3.3
stationary phase
separation material for separation of substances in an analyte
Note 1 to entry: separation materials, including but not limited to silica gel, aluminum oxide, octadecylsilane bonded
silica gel, polyamide, etc., are solid and are uniformly spread into a thin layer, or need to be laid on a flat support
material made of glass, metal or plastic.
3.4
chromogenic reagent
reagent that reacts with certain chemical groups, present or induced, in cells and tissues with the formation
of a coloured compound in situ
EXAMPLE Diazonium salt; Schiff’s reagent.
[SOURCE: ISO 19001:2013, 3.3]
Note 1 to entry: cells and tissues are replaced by stationary phase in this document.
3.5
retardation factor value
Rf-value
R Value
F
ratio from distance travelled by a given component divided by the distance travelled by the solvent front in
thin layer chromatography
[SOURCE: ISO 19609-2:2021, 3.7, modified]
Note 1 to entry: solvent front refers to the furthest point reached by the mobile phase as it ascends the plate.
4 Apparatus
4.1 Plate
TLC plate is composed of support material and stationary phase. Support material can be glass plate,
plastic plate, or aluminum. Common stationary phases include silica gel, bonded silica gel, microcrystalline
cellulose, polyamide, aluminum oxide, etc. Pre-coated plates are classified as TLC plates (10 μm to 40 μm)
and high-performance TLC (HPTLC) plates (2 μm to 10 μm) based on the particle size of silica gel. The
stationary phase may also be mixed with binder (plaster-of-Paris, abbreviated as G, or a polymeric binder)
and fluorescent indicator (F ), such as silica gel GF .
254 254
The detailed information of stationary phases and preparation method of TLC plate can refer to Clauses 6
and 22, World Health Organization: Quality control methods for herbal materials, 2011.
4.2 Application device
Micro syringes, calibrated microliter capillaries, or other hand-operated or automatic application devices
suitable for the proper application of the solutions.
4.3 Chromatographic chamber
For vertical development, a flat-bottom or twin-trough chamber of tra
...

FINAL DRAFT
International
Standard
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Requirement for (high-
Voting begins on:
performance) thin-layer
2026-09-08
chromatography [(HP)TLC]
Voting terminates on:
identification methods for
2026-11-03
medicinal herbs and natural
products
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 249/SC 1
Traditional Chinese medicine —
Secretariat: SAC
Requirement for (high-
Voting begins on:
performance) thin-layer
chromatography [(HP)TLC]
Voting terminates on:
identification methods for
medicinal herbs and natural
products
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2026
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 2
4.1 Plate .2
4.2 Application device .3
4.3 Chromatographic chamber .3
4.4 Derivatization device .3
4.5 Detection device .3
5 Procedure for (HP)TLC analysis . . 3
5.1 Storage and pretreatment of TLC plates .3
5.2 Sample application .4
5.3 Development .4
5.3.1 General .4
5.3.2 Vertical development .4
5.3.3 Horizontal development .5
5.4 Derivatization . .5
5.5 Detection .5
6 Evaluation . 5
7 Documentation . 6
Annex A (informative) TLC identification of Panax ginseng root and rhizome . 7
Annex B (informative) TLC identification of Fufang Danshen Tablet . 9
Annex C (informative) Reference values of (HP)TLC method in different pharmacopoeias .11
Bibliography .13

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 249, Traditional medicine, Subcommittee SC 1,
Traditional Chinese medicine.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Thin-layer chromatography (TLC) is one of the most widely employed techniques in planar chromatography.
It is a separation technique for samples through migration of solutes in the mobile phase, based on
mechanisms such as adsorption, partition, ion-exchange or combinations thereof. The separated components
are subsequently inspected under ultraviolet or visible light, either prior to or after derivatization with a
derivatization reagent.
High-performance thin-layer chromatography (HPTLC) is an advanced form of TLC that employs high-
quality percolated plates with smaller particle size and narrower particle size distributions, together with
automated sample application, controlled development conditions, and densitometry detection, to achieve
improved resolution, sensitivity, reproducibility, and quantitative capability.
(HP)TLC exhibits the following characteristics:
a) image-based data representation – the analytical results are directly presented as spatially
resolved images on the plate, enabling in situ visualization of separated components and facilitating
interpretation;
b) efficiency – the analysis time is relatively short, allowing multiple samples to be separated
simultaneously, thereby facilitating comparisons among them;
c) flexibility – parameters at each step (i.e. sample application, chromatographic development,
visualization, detection, documentation, and evaluation) can be adjusted as required;
d) convenient derivatization – post-chromatographic derivatization is straightforward, enabling multi-
dimensional chemical and bioactivity analyses to be conducted after separation.
The advantages of high throughput, flexibility and image-based visualization render (HP)TLC a valuable tool
for the qualitative identification of botanical drugs across various pharmacopoeias, including the Chinese
Pharmacopoeia, Japanese Pharmacopoeia, Korean Pharmacopoeia, British Pharmacopoeia, European
Pharmacopoeia, United State Pharmacopoeia, Indian Pharmacopoeia, as well as International Standards.
However, (HP)TLC is a multi-step technique, and many of its operations are carried out in an open
environment. Consequently, factors such as the quality of the stationary phase, environmental conditions
(including temperature and humidity), and operator proficiency can significantly influence analytical
results compared with other analytical techniques. Therefore, it is essential to standardize and harmonize
key parameters to ensure the reliability and comparability of results without compromising the flexibility of
the technique or increasing analytical costs.
Several national pharmacopoeias have established specific requirements for (HP)TLC analysis; however,
discrepancies in key parameters among these pharmacopoeias can adversely affect the accuracy and
comparability of results. Therefore, establishing the requirements for a harmonized (HP)TLC method is
necessary to enhance its applicability and ensure repeatability across various applications.
To facilitate the understanding and application of this document, Annex A and Annex B provide two
examples, representing medicinal herbs and preparations, respectively, together with representative
parameter settings and result descriptions. A comparison of representative (HP)TLC parameters across
different pharmacopoeias and standards is provided in Annex C.

v
FINAL DRAFT International Standard ISO/FDIS 25187:2026(en)
Traditional Chinese medicine — Requirement for (high-
performance) thin-layer chromatography [(HP)TLC]
identification methods for medicinal herbs and natural
products
1 Scope
This document specifies requirements of thin-layer chromatography (TLC) and high-performance thin layer
chromatography (HPTLC) identification methods for traditional Chinese medicine.
This document is applicable to medicinal herbs, preparations, oils, fats, extractives, and other natural
products used in traditional Chinese medicine worldwide.
2 Normative references
There is no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
thin-layer chromatography
TLC
technique in analytical chemistry used to separate, identify and quantify each component in a mixture via a
thin layer consisting of a stationary phase (3.4)
Note 1 to entry: TLC may also be used for semi-quantitative or quantitative analysis, where applicable.
Note 2 to entry: When using silica gel as the stationary phase, TLC plates typically consist of particles with a size range
of 5 µm to 40 µm, with an average particle size of 10 µm to 15 µm and a layer thickness of approximately 250 µm.
3.2
high-performance thin-layer chromatography
HPTLC
advanced form of thin-layer chromatography (3.1) that employs high-efficiency stationary phases, controlled
development conditions, and instrumental detection to achieve improved resolution, sensitivity, and
reproducibility
Note 1 to entry: HPTLC commonly involves automated sample application and densitometric detection.
Note 2 to entry: When using silica gel as the stationary phase, HPTLC plates typically consist of particles with a size
range of 2 µm to 10 µm, with an average particle size of 3 µm to 7 µm and a layer thickness of approximately 200 µm.

3.3
reference material
material or substance, one or more of whose property values are sufficiently homogeneous and well
established to be used for the calibration of an apparatus, the assessment of a measurement method, or for
assigning values to materials
[SOURCE: ISO Guide 30]
Note 1 to entry: Reference materials may include reference substances (standards), reference drug and the reference
extractive (extract).
Note 2 to entry: A reference solution is prepared by dissolving a reference material in a suitable solvent or by other
specified procedures. Such solutions may be referred to as standard solutions, reference substance solutions, reference
drug solutions, or reference extractive (extract) solution, as appropriate.
3.4
stationary phase
phase that remains fixed in place and enables the separation of components in a sample during
chromatography
Note 1 to entry: Typical stationary phase materials include silica gel, alumina, octadecylsilane (C18)-bonded silica gel,
polyamide.
Note 2 to entry: In thin-layer chromatography, the stationary phase is usually in the form of a thin layer uniformly
coated on a flat support, such as glass, metal or plastic.
3.5
chromogenic reagent
derivatization reagent
reagent that reacts with certain chemical groups present or induced in stationary phases (3.4) with the
formation of a coloured compound in situ
EXAMPLE Diazonium salt, Schiff’s reagent.
[SOURCE: ISO 19001:2013, 3.3, modified — The words "cells and tissues" have been replaced by "stationary
phases" and the term “derivatization reagent” have been added.]
3.6
Rf-value
R
F
retardation factor value
distance travelled by a given component divided by the distance travelled by the solvent front in thin-layer
chromatography (3.1)
Note 1 to entry: Solvent front refers to the furthest point reached by the mobile phase as it ascends the plate.
[SOURCE: ISO 19609-2:2021, 3.7, modified — The symbol "R ", the abbreviated term " retardation factor
F
value" and note 1 to entry have been added.]
4 Apparatus
4.1 Plate
The TLC or HPTLC plate consists of a support and a stationary phase. Common stationary phases include
silica gel, bonded silica gel, microcrystalline cellulose, polyamide, alumina. Pre-coated plates are classified as
TLC plates and high-performance TLC (HPTLC) plates based on the particle size of silica gel. The stationary
phase may contain a binder (calcium sulfate, abbreviated as G, or polymeric binders) and a fluorescent
indicator (e.g., F ), such as silica gel GF .
254 254
Detailed information about stationary phases and the preparation method of the TLC plate can be found in
Clauses 6 and 22 of Reference [8].

4.2 Application device
Micro syringes, calibrated microliter capillaries, or other hand-operated or automated devices shall be used
for application of test and reference solutions.
4.3 Chromatographic chamber
For vertical development, a flat-bottom or twin-trough chamber made of transparent material, usually
glass, with a tightly fitting lid and of suitable size to accommodate the plates, shall be used. For horizontal
development, a specially designed chamber shall be used.
4.4 Derivatization device
A glass sprayer or an appropriate spraying device shall be used for derivatization by spraying, with
compressed gas employed to disperse the derivatization reagent as a uniform mist. For imme
...

Formatted
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
ISO/TC 249/SC 1
Style Definition
...
Style Definition
...
Secretariat: SAC
Style Definition
...
Date: 2026-07-08-25
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Traditional Chinese medicine — Requirement for (high-
Style Definition
...
performance) thin-layer chromatography [(HP)TLC] identification
Style Definition
...
methods for medicinal herbs and natural products
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
FDIS stage
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
St l D fi iti
Formatted: Font: Bold
Formatted: HeaderCentered
Formatted: Default Paragraph Font
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
Formatted: Right: 1.5 cm, Bottom: 1 cm, Gutter: 0 cm,
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
Header distance from edge: 1.27 cm, Footer distance
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
from edge: 0.5 cm
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Formatted: French (France)
EmailE-mail: [e-mail]
Formatted: French (France)
Website: www.iso.orgwww.iso.org
Formatted: French (France)
Published in Switzerland
Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: Font: 11 pt
ii © ISO/DIS 25187 2026 – All rights reserved
ii
Formatted: Font: Bold
Formatted: HeaderCentered, Left
Contents Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 2
4.1 Plate . 2
4.2 Application device . 3
4.3 Chromatographic chamber . 3
4.4 Derivatization device. 3
4.5 Detection device . 3
5 Procedure for (HP)TLC analysis . 3
5.1 Storage and pretreatment of TLC plates . 3
5.2 Sample application . 4
5.3 Development . 4
5.4 Derivatization . 5
5.5 Detection . 5
6 Evaluation . 6
7 Documentation . 6
Annex A (informative) TLC identification of Panax ginseng root and rhizome . 7
Annex B (informative) TLC identification of Fufang Danshen Tablet . 9
Annex C (informative) Reference values of (HP)TLC method in different pharmacopoeias . 11
Bibliography . 13

Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 2
4.1 Plate . 2
4.2 Application device . 2
4.3 Chromatographic chamber . 2
4.4 Derivatization device. 2
4.5 Detection device . 3
5 Procedure for TLC analysis . 3
5.1 Storage and pretreatment of TLC plate . 3
5.2 Sample application . 3
5.3 Development . 3
Formatted: Font: 10 pt
5.3.1 Vertical development . 4
Formatted: FooterCentered, Left, Space Before: 0 pt,
5.3.2 Horizontal development . 4
Tab stops: Not at 17.2 cm
5.4 Derivatization . 4
5.5 Detection . 4
Formatted: Font: 11 pt
iii
Formatted: Font: Bold
Formatted: HeaderCentered
6 Evaluation . 5
7 Documentation . 5
Annex A (informative) TLC Identification of Panax ginseng root and rhizome . 6
Annex B (informative) TLC Identification of Fufang Danshen Tablet . 8
Annex C (informative) Reference values of TLC method in different pharmacopoeias . 10
Bibliography . 12
Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: Font: 11 pt
iv © ISO/DIS 25187 2026 – All rights reserved
iv
Formatted: Font: Bold
Formatted: HeaderCentered, Left
Foreword Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Formatted: English (United Kingdom)
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents.www.iso.org/patents. ISO shall not be held responsible for identifying any or all such
patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html.
Formatted: English (United Kingdom)
This document was prepared by Technical Committee ISO/TC 249, Traditional medicine, Subcommittee SC 1,
Formatted: Adjust space between Latin and Asian text,
Traditional Chinese medicine.
Adjust space between Asian text and numbers
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.htmlwww.iso.org/members.html.
Formatted: Font: 10 pt
Formatted: FooterCentered, Left, Space Before: 0 pt,
Tab stops: Not at 17.2 cm
Formatted: Font: 11 pt
v
Formatted: Font: Bold
Formatted: HeaderCentered
Introduction
Thin-layer chromatography (TLC) is one of the most widely employed techniques in planar chromatography.
It is a separation technique for samples through migration of solutes in the mobile phase, based on
mechanisms such as adsorption, partition, ion-exchange or combinations thereof. The separated components
are subsequently inspected under ultraviolet or visible light, either prior to or after derivatization with a
derivatization reagent.
High-performance thin-layer chromatography (HPTLC) is an advanced form of TLC that employs high-quality
percolated plates with smaller particle size and narrower particle size distributions, together with automated
sample application, controlled development conditions, and densitometry detection, to achieve improved
resolution, sensitivity, reproducibility, and quantitative capability.
(HP)TLC exhibits the following characteristics:
a) a) image-based data representation – the analytical results are directly presented as spatially
resolved images on the plate, enabling in situ visualization of separated components and facilitating
interpretation;
b) b) efficiency – the analysis time is relatively short, allowing multiple samples to be separated
simultaneously, thereby facilitating comparisons among them;
c) c) flexibility – parameters at each step (i.e. sample application, chromatographic development,
visualization, detection, documentation, and evaluation) can be adjusted as required;
d) d) convenient derivatization – post-chromatographic derivatization is straightforward, enabling
multi-dimensional chemical and bioactivity analyses to be conducted after separation.
The advantages of high throughput, flexibility and image-based visualization render (HP)TLC a valuable tool
Formatted: Adjust space between Latin and Asian text,
for the qualitative identification of botanical drugs across various pharmacopoeias, including the Chinese
Adjust space between Asian text and numbers
Pharmacopoeia, Japanese Pharmacopoeia, Korean Pharmacopoeia, British Pharmacopoeia, European
Pharmacopoeia, United State Pharmacopoeia, Indian Pharmacopoeia, as well as International Standards.
However, (HP)TLC is a multi-step technique, and many of its operations are carried out in an open
environment. Consequently, factors such as the quality of the stationary phase, environmental conditions
(including temperature and humidity), and operator proficiency can significantly influence analytical results
compared with other analytical techniques. Therefore, it is essential to standardize and harmonize key
parameters to ensure the reliability and comparability of results without compromising the flexibility of the
technique or increasing analytical costs.
Several national pharmacopoeias have established specific requirements for (HP)TLC analysis; however,
discrepancies in key parameters among these pharmacopoeias can adversely affect the accuracy and
comparability of results. Therefore, establishing the requirements for a harmonized (HP)TLC method is
necessary to enhance its applicability and ensure repeatability across various applications.
To facilitate the understanding and application of this document, Annex A and Annex BAnnex A and Annex B
provide two examples, representing medicinal herbs and preparations, respectively, together with
representative parameter settings and result descriptions. A comparison of representative (HP)TLC
parameters across different pharmacopoeias and standards is provided in Annex C.Annex C.

Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: Font: 11 pt
vi © ISO/DIS 25187 2026 – All rights reserved
vi
DRAFT International Standard ISO/FDIS 25187:2026(en)

Formatted: Left
Traditional Chinese medicine — Requirement for (high-performance)
thin-layer chromatography [(HP)TLC] identification methods for
medicinal herbs and natural products
1 Scope Formatted: Right: 1.5 cm, Bottom: 1 cm, Gutter: 0 cm,
Header distance from edge: 1.27 cm, Footer distance
This document specifies requirements of thin-layer chromatography (TLC) and high-performance thin layer from edge: 0.5 cm
chromatography (HPTLC) identification methods for traditional Chinese medicine.
This document is applicable to medicinal herbs, preparations, oils, fats, extractives, and other natural products
used in traditional Chinese medicine worldwide.
2 Normative references
There is no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/https://www.electropedia.org/
3.1 3.1
thin-layer chromatography
TLC
technique in analytical chemistry used to separate, identify and quantify each component in a mixture via a
thin layer consisting of a stationary phase (3.4)(3.4)
Note 1 to entry: TLC may also be used for semi-quantitative or quantitative analysis, where applicable.
Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers, Tab
Note 2 to entry: When using silica gel as the stationary phase, TLC plates typically consist of particles with a size range
stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm +
of 5 µm to 40 µm, with an average particle size of 10 µm to 15 µm and a layer thickness of approximately 250 µm.
3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
3.2 3.2
high-performance thin-layer chromatography
HPTLC
advanced form of thin-layer chromatography (3.1)(3.1) that employs high-efficiency stationary phases,
controlled development conditions, and instrumental detection to achieve improved resolution, sensitivity,
and reproducibility
Note 1 to entry: HPTLC commonly involves automated sample application and densitometric detection.
Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers, Tab
Note 2 to entry: When using silica gel as the stationary phase, HPTLC plates typically consist of particles with a size
stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm +
range of 2 µm to 10 µm, with an average particle size of 3 µm to 7 µm and a layer thickness of approximately 200 µm.
3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
Formatted: Font: Bold
Formatted: HeaderCentered
3.3 3.3
reference material
material or substance, one or more of whose property values are sufficiently homogeneous and well
Formatted: English (United Kingdom)
established to be used for the calibration of an apparatus, the assessment of a measurement method, or for
assigning values to materials
Formatted: Default Paragraph Font
[SOURCE: ISO Guide 30] Formatted: Default Paragraph Font
Formatted: Default Paragraph Font
Note 1 to entry: Reference materials may include reference substances (standards), reference drug and the reference
Formatted: Adjust space between Latin and Asian text,
extractive (extract).
Adjust space between Asian text and numbers
Note 2 to entry: A reference solution is prepared by dissolving a reference material in a suitable solvent or by other
Formatted: Adjust space between Latin and Asian text,
specified procedures. Such solutions may be referred to as standard solutions, reference substance solutions, reference
Adjust space between Asian text and numbers, Tab
drug solutions, or reference extractive (extract) solution, as appropriate.
stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm +
3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
3.4 3.4
Formatted: Adjust space between Latin and Asian text,
stationary phase
Adjust space between Asian text and numbers, Tab
phase that remains fixed in place and enables the separation of components in a sample during
stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm +
chromatography
3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
Note 1 to entry: Typical stationary phase materials include silica gel, alumina, octadecylsilane (C18)-bonded silica gel,
Formatted: Regular, Font: Bold
polyamide.
Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers, Tab
Note 2 to entry: In thin-layer chromatography, the stationary phase is usually in the form of a thin layer uniformly
stops: Not at 0.7 cm + 1.4 cm + 2.1 cm + 2.8 cm +
coated on a flat support, such as glass, metal or plastic.
3.5 cm + 4.2 cm + 4.9 cm + 5.6 cm + 6.3 cm + 7 cm
3.5 3.5 Formatted: Default Paragraph Font
chromogenic reagent
Formatted: Adjust space between Latin and Asian text,
derivatization reagent
Adjust space between Asian text and numbers
reagent that reacts with certain chemical groups present or induced in stationary phases (3.4)(3.4) with the
Formatted: Default Paragraph Font
formation of a coloured compound in situ
Formatted: Default Paragraph Font
EXAMPLE: Diazonium salt, Schiff’s reagent.
Formatted: Default Paragraph Font
Formatted: Regular Italic, Font: Bold, Not Italic
[SOURCE: ISO 19001:2013, 3.3, modified — The words "cells and tissues" have been replaced by "stationary
phases" and the term “derivatization reagent” have been added.]
Formatted
...
Formatted: Regular, Font: Bold
3.6 3.6
Rf-value Formatted
...
R
F
Formatted: Default Paragraph Font
retardation factor value
Formatted: Default Paragraph Font
distance travelled by a given component divided by the distance travelled by the solvent front in thin-layer
chromatography (3.1)(3.1) Formatted: Default Paragraph Font
Formatted: Default Paragraph Font
Note 1 to entry: Solvent front refers to the furthest point reached by the mobile phase as it ascends the plate.
Formatted: Default Paragraph Font
[SOURCE: ISO 19609-2:2021, 3.7, modified — The symbol "R ", the abbreviated term " retardation factor
F
Formatted: Default Paragraph Font
value" and note 1 to entry have been added.]
Formatted: Default Paragraph Font
4 Apparatus Formatted
...
Formatted: Default Paragraph Font
4.1 Plate
Formatted
...
The TLC or HPTLC plate consists of a support and a stationary phase. Common stationary phases include silica
Formatted: Font: 10 pt
gel, bonded silica gel, microcrystalline cellulose, polyamide, alumina. Pre-coated plates are classified as TLC
Formatted: Font: 10 pt
plates and high-performance TLC (HPTLC) plates based on the particle size of silica gel. The stationary phase
Formatted: Font: 11 pt
2 © ISO/DIS 25187 2026 – All rights reserved
Formatted: Font: 11 pt, Bold
Formatted: Font: Bold
Formatted: HeaderCentered, Left
may contain a binder (calcium sulfate, abbreviated as G, or polymeric binders) and a fluorescent indicator
(e.g., F ), such as silica gel GF .
254 254
Detailed information about stationary phases and the preparation method of the TLC plate can be found in
Clauses 6 and 22 of World Health Organization: Quality control methods for herbal materials, 2011.Reference
Formatted: Default Paragraph Font
[8].
4.2 Application device
Micro syringes, calibrated microliter capillaries, or other hand-operated or automated devices shall be used
Formatted: Adjust space between Latin and Asian text,
for application of test and reference solutions.
Adjust space between Asian text and numbers
4.3 Chromatographic chamber
For vertical development, a flat-bottom or twin-trough chamber made of transparent material, usually glass,
Formatted: Adjust space between Latin and Asian text,
with a tightly fitting lid and of suitable size to accommodate the plates, shall be used. For horizontal
Adjust space between Asian text and numbers
development, a specially designed chamber shall be used.
4.4 Derivatization device
A glass sprayer or an appropriate spraying device shall be used for derivatization by spraying, with
Formatted: Adjust space between Latin and Asian text,
compressed gas employed to disperse the derivatization reagent as a uniform mist. For immersion
Adjust space between Asian text and numbers
derivatization, a suitably sized glass chamber or apparatus shall be used. For fumigation derivatization, a
properly sized glass chamber shall be used. A suitable heating device capable of maintaining stable and
uniform temperature shall be used to facilitate derivatization.
4.5 Detection device
A device equipped with appropriate light sources,
...