A new and highly sensitive TLC method to measure hypericin using chemiluminescence

ABSTRACT

Hypericin is a polyphenolic compound belonging to the group of polyphenols and is the active constituents of Hypericum perforatum (Saint John’s wort). We present a new high-performance thin-layer chromatography (HPTLC) method to measure a large number of hypericin extracts using chemiluminescence. On a 10 × 10 cm HPTLC plate (LiChrospher® Merck, 1.05586), more than 40 tracks can be simultaneously quantified using a piezoelectric application system (pipeJet) which can apply 56 nL of a methanolic hypericin extract contactless with high precision. For separation, a solvent mixture of ethyl acetate, water, formic acid, methyl tert-butyl ether, and cyclohexane (180 + 14 + 14 + 80 + 30, v/v) was used. The R_f-value of hypericin is 0.27. The method presented is specific for hypericin and offers a limit of quantification of 690 pg hypericin per band.

GRAPHICAL ABSTRACT

KEYWORDS:

• Chemiluminescence
• Hypericum perforatum
• HPTLC
• hypericin
• Saint John’s wort
• TLC

Acknowledgments

The authors express their appreciation to Merck-Company (Darmstadt, Germany), biostep (Burkhardtsdorf, Germany) and CAMAG (Muttenz, Switzerland) for their kind support.