Liquid chromatography-mass spectrometry-based determination of ergocristine, ergocryptine, ergotamine, ergovaline, hypoglycin A, lolitrem B, methylene cyclopropyl acetic acid carnitine, N-acetylloline, N-formylloline, paxilline, and peramine in equine hair.

The study describes a method of using liquid chromatography-mass spectrometry to determine the presence of particular toxins and compounds in horse hair. The method helps identify the ingestion of harmful substances, such as hypoglycin A and alkaloids produced by fungi in grass, in grazing animals which can lead to various syndromes.

Methodology

• The researchers developed analytical methods to monitor the long-term exposure to hypoglycin A (HGA), its metabolite MCPA-carnitine, and other toxins such as ergocristine, ergocryptine, ergotamine, ergovaline, lolitrem B, N-acetylloline, N-formylloline, peramine, and paxilline in equine hair.
• Hair samples were extracted and separation was achieved using two ultra high performance liquid chromatographic systems (HILIC or RP-C18, ammonium formate:acetonitrile).
• A benchtop orbitrap instrument was used for high resolution tandem mass spectrometric detection.

Results

• All the analytes were sensitively detected with limits of detection between 1 pg/mg and 25 pg/mg.
• Issues related to irreproducible extraction or ubiquitous presence in horse hair hindered the quantitative validation of lolitrem B/paxilline and N-acetylloline/N-formylloline.
• For the other analytes, the validation showed no interferences in blank hair.
• Other validation parameters included: limits of quantification (LOQ), recoveries, matrix effects, linearity, accuracy, and precision RSDs.

Conclusions

• The study reveals that the method allows precise detection of all analytes and enables quantification of ergocristine, ergocryptine, ergotamine, ergovaline, HGA, MCPA-carnitine, and peramine in horse hair.
• The applicability of the method for N-acetylloline and N-formylloline was validated through the analysis of hair from 13 horses.