The liquid chromatography/tandem mass spectrometry (LC-MS/MS) method can identify markers for horse meat and the veterinary drug phenylbutazone (bute).
It detects the protein markers distinct to specific meat species and enables laboratories to detect veterinary drug residues in the same analysis, which is not possible by ELISA (enzyme-linked immunosorbent assay) or polymerase chain reaction (PCR).
While the method was optimized to identify horse tissue contamination in beef samples, it may also be adapted to detect peptide markers of different animal types simultaneously.
It can also identify horse meat that may be present in other tissue samples (such as pork, beef or lamb) by its unique protein markers.
It will allow laboratory scientists to analyse a single meat sample for 15-20 different animal species in a single run, with very little chance of false positives, said the firm.
Increasing options
Steve Lock, technical market applications manager, food and environmental, AB Sciex told FoodQualityNews.com that work is planned to add more markers to the method and increase the number of species that can be detected.
“We are at the forefront as no-one else has tests that can detect protein markers and bute at the same time and in the same test. We are ahead of the game and the market on applications development.
"A lot of labs have LC-MS facilities which enable them to offer alternative routes to solving problems, and provide the labs with food testing tools in order to respond quickly to scares.
"There is an increase in improvement in sensitivity with LC-MS, which can provide multiple tests in a single analysis as well as cut down the risk of false positives."
When asked about the challenges, Lock said “We need to make sure the markers are specific to the species as we don’t want false positives. There are no methods to detect some of the rarer animals as their DNA and the proteins they produce are not yet sequenced.
"We have this information for pig, beef and lamb, but markers still need to be developed to detect the species for which we don’t have any sequence information.”
AB SCIEX scientists used the method in a LGC Standards proficiency testing scheme, which initially confirmed detection at levels of 10% with no false positives. Further method refinement has now been carried out to achieve levels of 1%.
Technology value
Ashley Sage, technical market development manager for the food and environment business EMEA, told us that the technology has already shown its worth in terms of speed and sensitivity.
“LC-MS/MS based solutions offer the capability of comprehensive, multi-analyte screening in a single analysis, which will become faster as technology and detection gets better.
“This will benefit the customer base as there is a faster turnaround, of about a day with samples done in the morning and results back by the end of the day.”