Production of source material

Most qRE reference extracts are prepared from plants grown in our botanical garden. This allows us to monitor every stage of their life-cycle and certify their botanical identity with confidence. Tropical and arctic species are provided by reliable professionals, from known sources and locations. All raw material is authenticated on arrival at the laboratory.

The parts of the plants to be extracted are collected at the proper time in their growth cycle to ensure the optimum concentration of their useful compounds.

See botanical garden for more details on how we grow and authenticate our plants.


Production of dry extract

The plants or plant parts are cut and freeze-dried right after collection. The freeze-dried plants are extracted by maceration at room temperature for 48 h in ethanol-water 50 % (v/v) mix (unless specified otherwise in the corresponding Technical Documentation).


Compound quantification and identification process

All significant molecules (those with the highest concentration or the ones most important for their activities) are identified by HPLC-ESIHR-MSMS. Among them, one or two molecules are used as internal standards and are separately quantified by qNMR (incertitude ± 4.5%).

An HPLC-CAD (charged Aerosol Detector) is performed.
CAD produces a response which is similar but not fully identical from a non-volatile molecule to another, as shown by Robinson et al. 20171, and Schilling et al. 20192.
Our laboratory, the Institut des Substances Végétales, developed a proprietary algorithm to recalculate the signal in order to obtain identical responses between different molecules within a relative incertitude range of ± 7.5 %.

Download PDF summary of the analytical methods.


Retesting schedule

To check the validity of quantitative values provided in the Certificate of Analysis, a retest is performed every 12 months following the manufacture date indicated on the CoA, during 3 years.

Retests are performed on the quantitative values and the HPLC profile’s compliance is checked.

A new Certificate of Analysis is then produced, available to customers on request.

The retesting date is specified on the product’s label and on its Certificate of Analysis. It is also indicated on the Analytical Results Card enclosed in each qRE box.



(1) Use of Calculated Physicochemical Properties to Enhance Quantitative Response When Using Charged Aerosol Detection. Max W. Robinson, Alan P. Hill, Simon A. Readshaw, John C. Hollerton, Richard J. Upton, Sean M. Lynn, Steve C. Besley, and Bob J. Boughtflower. Anal. Chem. 2017, 89, 1772−1777

(2) Quantitative structure-property relationship modeling of polar analytes lacking UV chromophores to charged aerosol detector response. Klaus Schilling & Jovana Krmar & Nevena Maljurić & Ruben Pawellek & Ana Protić & Ulrike Holzgrab. Analytical and Bioanalytical Chemistry. 2019, 411, 13, 2945–2959

Laboratory HPLC