Determination of succinonitrile in horse urine by gas chromatography-nitrogen-phosphorus detector and gas chromatography-mass spectrometry.

This study presents a method to detect succinonitrile (SDN), a banned substance, in horse urine using gas chromatography techniques. This new approach provides an effective tool for anti-doping monitoring in horse racing.

Methodology

• The researchers have developed a chromatographic method to detect and confirm the presence of succinonitrile (SDN) in horse urine samples. This procedure has been designed to support and enhance the effectiveness of anti-doping controls in horse racing.
• The detection method relied on two primary techniques: gas chromatography-nitrogen-phosphorus detector (GC-NPD) and gas chromatography-mass selective detection (GC-MSD). Both are sensitive and specific procedures for identifying and quantifying compounds in samples.

Procedure and Findings

• The approach begins with the extraction of samples using diethyl ether. The research utilized urine samples of 5 ml each.
• After extraction, the samples were screened by the gas chromatography-nitrogen-phosphorus detector. The role of the GC-NPD is to identify the presence of SDN in the samples.
• The confirmation of the drug’s presence was accomplished by using gas chromatography-mass selective detection. Using the GC-MSD technique allows the scientists to confirm the presence and quantity of SDN in the samples.
• The recovery of extraction, i.e., the percentage of SDN retrieved after the extraction process, was 78% for 1.0 micrograms mL-1 and 81% for 2.0 micrograms mL-1. The relative standard deviation was less than 10%, indicating that the method has good precision.
• In the study, urine samples collected after the administration of Energisan were tested. Energisan is a medicine often used in veterinary medicine, and, in this case, was used to introduce SDN into the horses’ systems. The tests were positive for SDN in the range 1-30 hours in all samples analyzed, supporting the effectiveness of the method in the detection and confirmation of SDN.