Psoralen dosage

Psoralen testing allows the detection and quantification of this photosensitizing compound present in certain plants, plant extracts, and essential oils. Performed by HPLC (high-performance liquid chromatography) or LC-MS (liquid chromatography-mass spectrometry), this analysis is essential for monitoring the safety of cosmetic and herbal products exposed to UV light.

Psoralen: a natural furocoumarin with photosensitizing potential

Psoralen belongs to the family of furocoumarins , natural molecules present in several aromatic and medicinal plants such as :

• the fig (Ficus carica),
• celery graveolens ),
• parsley ,​
• lime ,​
• or certain Rutaceae (bergamot, bitter orange, angelica, etc.).

These compounds have a coumarin nucleus fused to a furan ring , giving them high reactivity under UV irradiation. In cosmetics or phytotherapy, they can induce phototoxic reactions when applied to the skin before sun exposure.

Psoralen and its derivatives (xanthotoxin, bergapten, isopsoralen) are therefore subject to strict regulatory limits in products intended for cutaneous use, in particular perfumes, essential oils or photosensitizing plant preparations.

Objectives and interest of psoralen dosage

The dosage of psoralen aims to:

• ensure the safety of cosmetic products by controlling the concentrations of photosensitizing furocoumarins,
• verify regulatory compliance (cosmetic regulation EC no. 1223/2009),
• standardize plant extracts used in phytotherapy,
• identify plant sources at risk in essential oil blends,
• prevent adverse skin reactions related to UV exposure.

Affected matrices include:

• plant extracts , powders and macerates,
• essential oils ( including bergamot, lemon, celery, angelica),
• cosmetic preparations ( creams, lotions, perfumes),
• food supplements based on photosensitizing plants.

Analytical methods used

Psoralen is analyzed by HPLC-DAD (diode array detection) or LC-MS/MS , allowing accurate quantification even at low concentrations.

• HPLC-DAD : Used for routine determination, this technique separates furocoumarins on a C18 column and detects their characteristic signals in the UV (310–320 nm).
• LC-MS/MS : offers superior specificity , allowing the simultaneous identification of psoralen and its structural derivatives (bergapten, xanthotoxin, isopsoralen) in complex matrices.

The results are expressed in mg/kg or ppm , depending on the type of matrix and the applicable regulations.

This analysis can be combined with other complementary tests:

• Bergapten (5-MOP) dosage,
• Xanthotoxin dosage,
• Determination of flavonoids by HPLC,
• Analysis of essential oils by GC-MS.

Industrial and regulatory applications

Psoralen dosage is required in several contexts:

• Cosmetics : Control of photosensitizing essential oils used in creams, perfumes, massage oils, and hair care products. European regulations limit the total furocoumarin content to 1 mg/kg in leave-on products exposed to sunlight.
• Phytotherapy : standardization of plant extracts rich in furocoumarins (psoralea, angelica, celery) to guarantee a safe and reproducible composition.
• Agri-food and nutraceuticals : monitoring of potentially phototoxic plant ingredients used in supplements or functional drinks.
• Research and quality control : identification of furocoumarins in studies of plant composition, drug interactions or photoactive efficacy.

Analyses are often integrated into comprehensive quality control plans, including verification of other families of bioactive compounds such as flavonoids , saponins or simple coumarins .

Carrying out analyses at YesWeLab

YesWeLab collaborates with partner laboratories specialized in the characterization of photosensitizing plant compounds . Analyses are carried out using validated methods and comply with the requirements of the ISO 17025 .

Each request is studied according to:

• of the matrix to be analyzed ,
• applicable regulatory thresholds ,
• and analytical objectives (compliance, R&D, quality control).

Analysis reports include measured concentrations, detected derivatives and interpretive comments necessary for regulatory compliance.

Since 2020, YesWeLab has been supporting manufacturers of cosmetics, natural products and food supplements in controlling their plant-based formulations and preventing phototoxic risks.

Thanks to its digital platform, requesting, monitoring and receiving analysis results is simple and transparent.

Technical data

• Methods: HPLC-DAD, LC-MS/MS
• Expertise: Physicochemical, nutritional
• Sectors: Cosmetics, nutraceuticals, phytotherapy, aromatic plants
• Measured parameters: Psoralen and associated furocoumarins (bergapten, xanthotoxin, isopsoralen)
• Normative references: ISO 17025, Regulation (EC) No. 1223/2009, validated internal methods

For any specific request, contact our scientific team to obtain a personalized quote and technical support adapted to your products and regulatory constraints.