Evaluation of horse urine sample preparation methods for metabolomics using LC coupled to HRMS.

The research explores methodologies for preparing horse urine for metabolomics study using LC-HRMS, and concludes that acetonitrile precipitation is the most efficient method.

Overview and Objective of the Study

• The study is an investigation of various methods for horse urine sample preparation for metabolomics research. Metabolomics is the study of the full biochemical pathway within a biological sample, in this case, horse urine. The researchers are specifically interested in enhancing the controls for horse doping, which is a challenge due to the presence of various interfering compounds in horse urine.

Methodology and Results

• Five sample-preparation methods were examined: acetonitrile precipitation, proteinase K hydrolysis, membrane filtration and sample dilution with water at two different ratios (by factors of five and 20).
• The evaluation was performed using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS). This is a technique used in analytical chemistry to separate, identify, and quantify compounds in a sample.
• The assessment was carried out on both a global level, with features obtained from peak detection software, and a targeted level, using internal standards and 100 pre-identified metabolites. These internal standards and metabolites help to compare and validate the results obtained from each preparation method.

Conclusions

• Based on the analysis, acetonitrile precipitation was deemed the most efficient sample-preparation method for studying the horse urine metabolome with LC-HRMS.
• This conclusion was reached by considering the number of detected signals, the intensity of these signals, and the repeatability of their detection between samples prepared using the same method.

Significance of the Research

• The research offers valuable insights for the field of horse doping control. By identifying the most efficient preparation method, the study facilitates improved investigative approaches to detect doping substances.
• In a broader context, this study helps to refine the process of metabolome analysis, potentially contributing to progress in areas such as veterinary science, animal health, and competitive sports regulation.