Cris Lapthorn, Head of Mass Spectrometry, has helped understand more about the presence of antibiotics in foods, such as meat, fruit and honey. He has combined ion mobility and mass spectrometry techniques with computer molecular modelling.
The technique, which Cris was invited to present to a packed meeting at the American Society for Mass Spectrometry in Baltimore earlier this summer, promises to be able to better understand other problematic residues in foods such as insecticides, pesticides and steroids.
A former Head of Open-Access Mass Spectrometry for the pharmaceuticals giant Pfizer at Sandwich, Cris developed the new analytical approach as part of his doctoral research. The University of Greenwich Faculty of Engineering & Science’s investment in a Waters Synapt G2 IM-MS (ion mobility – mass spectrometry) instrument made the research possible.
To date, the majority of his work has focused on tracing the widely-prescribed broad spectrum antibiotic Norfloxacin in the food chain.
Cris says: “England’s Chief Medical Officer, Professor Dame Sally Davies, has described resistance to antibiotics as a catastrophic threat, on a par with terrorism, leading to deaths from routine minor surgery within 20 years.
“Antibiotics resistance is a danger for all consumers and drug residues in foods can cause serious reactions in hypersensitive individuals.
Traditionally mass spectrometry analysis of compounds has identified an antibiotic, such as Norfloxacin, as a single structure and therefore one component.
Ion mobility mass spectrometry and computer molecular modelling, looking at individual molecules of the drug, has revealed that Norfloxacin produces two markers of different intensity. The source of the second marker is not yet fully understood but offers analysts a way of identifying previously undetected residues of the antibiotic.
“It was a complete eye-opener,” says Cris. “We need to do more research but the implication is that previous detection techniques for substances such as antibiotics have been flawed.”
Cris’ poster presentation of his work won the British Mass Spectrometry Society Bordoli Award earlier this year and he was invited to tutor the society’s inaugural ion-mobility – mass spectrometry workshop.