Lab
Eike Reich's Lab
About the lab
We are a team of highly qualified personnel including chemists, pharmacists and laboratory technicians with more than 50 years of combined experience.
We participate in the elaboration of monographs for the:
Swiss Pharmacopeia (Ph. Helv.)
European Pharmacopeia (Ph. Eur)
United States Pharmacopeia (USP)
Chinese Pharmacopeia (Ch.P.)
American Herbal Pharmacopoeia (AHP).
We publish results of our work in scientific journals, textbooks, through conferences and seminars as well as on our website. It is our goal to make high quality data illustrating the capabilities of HPTLC available to the public.
We participate in the elaboration of monographs for the:
Swiss Pharmacopeia (Ph. Helv.)
European Pharmacopeia (Ph. Eur)
United States Pharmacopeia (USP)
Chinese Pharmacopeia (Ch.P.)
American Herbal Pharmacopoeia (AHP).
We publish results of our work in scientific journals, textbooks, through conferences and seminars as well as on our website. It is our goal to make high quality data illustrating the capabilities of HPTLC available to the public.
Featured research (8)
The European Pharmacopoeia (Ph. Eur.), includes both individual monographs on essential oils and a general monograph that covers all essential oils for pharmaceutical use, whether covered by an individual monograph or not. The individual monographs generally describe gas chromatography as a first identification test, while thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) methods are included in the second identification series. To comply with Ph. Eur. general chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, HPTLC parameters must be standardised. Currently, 18 of the 32 monographs on essential oils feature the same TLC/HPTLC method, but differ in terms of the other conditions described. A single, standardised chromatographic system with a system suitability test (SST) and intensity markers for all 32 essential oils covered by individual monographs would be desirable, particularly for pharmacies and other users that cannot perform gas chromatography for financial reasons.
To this end, this paper describes the development of a general HPTLC method for the identification of essential oils in compliance with general chapter 2.8.25. The method proposes the use of ethyl acetate, toluene (5:95 V/V) as mobile phase, isoeugenol/isoeugenyl acetate for the SST, and a combination of one alcohol (either borneol or linalool) and one ester (either linalyl acetate or bornyl acetate) as intensity markers.
The use of chromatographic methods in routine analysis includes System Suitability Tests (SST). This paper presents a novel approach to SST in HPTLC, which allows qualification of the entire RF range of an HPTLC plate independently of the samples. It is based on the Universal HPTLC mix (UHM), a pre-defined mixture of eight reference substances: guanosine, sulisobenzone, thymidine, paracetamol, phthalimide, 9-hydroxyfluorene, thioxanthen-9-one, and 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol, selected to cover a broad range of polarities and functional groups. The chromatographic behavior of the UHM was evaluated for 20 different mobile phases on Silica gel 60 F254. At least three constituents were base line separated. In a collaborative trial with four laboratories the reproducibility of RF values for three representative mobile phases, was found to be within a confidence interval of 0.040 RF units. The response characteristics of the UHM were assessed with respect to changes in chromatographic conditions, such as variation of the relative humidity, improperly employed saturation, or mistakes in the preparation of the mobile phase. Based on the RF values of the individual constituents significant responses were found for most changes. This qualifies the UHM for use in SST.
The species Sclerocarya birrea, also known as Marula, is present in Sub-Saharan Africa. In Burkina Faso, the leaves are sold as a traditional improved medicine with antidiabetic indication. The objective of this study was to develop a simple, rapid and robust high-performance thin-layer chromatographic (HPTLC) method for the reliable quality control of S. birrea leaves in Burkina Faso and other West African countries. Chromatography was performed using HPTLC Si 60 F254 plates (20 × 10 cm) as the stationary phase and ethyl acetate‒formic acid‒water (80:10:10, V/V) as the mobile phase. Derivatiza-tion steps using natural product and anisaldehyde reagents were used after the development for the detections of flavonoids and triterpenoids. Detection was carried out prior to and after derivatization under UV 254 nm, 366 nm and white light. The HPTLC method was successfully applied to the analysis of 182 collected samples including different origins, related herbal drugs (different plant parts, confounding species) and 12 traditional improved medicines in different forms (capsule, powdered sample, tea). The method was then adapted for use in quality control at different levels in developing countries.
Quality evaluation of herbal drugs requires the assessment of identity and possible adulterations, as well as the determination of the content of active principles or markers. For that, normally, different methods, using different chromatographic techniques are prescribed in the Pharmacopeia monographs. The goal of this work is to propose a new method for evaluation, based on “comprehensive high-performance thin layer chromatography (HPTLC) fingerprinting.” A single HPTLC analysis, which combines identification of Ganoderma lucidum fruiting body with a test for adulteration and quantitative determination of the content of total triterpene acids is proposed. Parameters of the HPTLC method were optimized for simplicity, and robustness. Then, 50 samples of G. lucidum fruiting body, plus samples of possible adulterating species were evaluated, proving specificity of the method for the targeted species. Triterpene acids were assayed by integrating
the peaks of ganoderic acids in the fingerprint, summing their areas, and quantifying them against a single level calibration point of ganoderic acid A. The presented HPTLC method offers an economic
yet powerful alternative to the current USP monograph on G. lucidum fruiting body. It combines identification and quantitative assessment in a single, low-cost test, eliminating the UHPLC assay of total triterpene acids. This way the samples’ quality can be comprehensively described.