Nitrofurazone quantification in milk at the European Union minimum required performance limit of 1 ng g⁻¹: circumventing the semicarbazide problem

Abstract

Nitrofurazone is an antibiotic with carcinogenic properties. Efforts by regulatory authorities to control nitrofurazone from agricultural foods are an important public health measure that have, to some extent, been undermined by widespread use amongst laboratories of the unreliable marker metabolite semicarbazide. This work confirms what has long been suspected, namely that powdered dairy products that are initially free of semicarbazide develop semicarbazide under storage conditions such as occur normally across commercial supply chains. The low ng g(-)(1) levels of semicarbazide formed in this way are insufficient to present any food safety hazard. That such development of a marker metabolite is demonstrated to occur by innocent means effectively invalidates the use of semicarbazide as a marker metabolite for powdered dairy products, and exacerbates the regulatory need for a more suitable analytical methodology. In milk, unlike meat, nitrofurazone is known to remain stable and thus available for analysis in the intact form, rather than necessitating any use of a metabolite or fragment. However, no previous methodology that was capable of achieving the stringent European minimum required performance limit of 1 ng g(-)(1) when using intact nitrofurazone had been described for milk. This work describes a specific methodology using LC-MS/MS for milk and milk powder; it achieves detection of intact nitrofurazone (as well as furazolidone, furaltadone and nitrofurantoin) to levels well below 1 ng g(-)(1). Laboratories will no longer need to use semicarbazide as an unreliable marker metabolite for the analysis of nitrofurazone in dairy products, paving the way for regulatory authorities to better control nitrofurazone abuse with greater confidence.

A New Derivatizing Agent for Determining Nitrofuran Metabolites in Chicken Eggs by High-Performance Liquid Chromatography–Tandem Mass Spectrometry

“…The data presented in Table 1 confirm that the interaction of nitrofuran metabolites with 5-NFA yielded the initial nitrofurans. The main characteristics coincided with the corresponding values for nitrofurans given in [40,41]. The yield of the derivatization reaction was 95-100%.…”

Temperature- and solvent-induced reversible single-crystal-to-single-crystal transformations of TbIII-based MOFs with excellent stabilities and fluorescence sensing properties toward drug molecules

“…[31][32][33] The traditional detection methods (high performance liquid chromatography-mass spectrometry and spectrophotometry) are complicated and of high cost. 22,34,35 Therefore, there is an urgent need for simple, rapid and efficient detection of the drugs. LMOF sensing can be used as a method to detect drugs due to their advantages in terms of definite fluorescence spectra, visible signals by the naked eye, high sensitivity and selectivity, and simplicity in operation.…”

Determination of Nitrofuran Metabolites in Complex Food Matrices Using a Rough, Cheap, Easy-Made Wooden-Tip-Based Solid-Phase Microextraction Probe and LC-MS/MS

“…HPLC-MS is considered the most efficient technique among these methods due to its reliability, sensitivity, and selectivity [24,26,28]. Although many HPLC-MS methods have been reported in recent years to detect nitrofuran derivatives in complex matrix foods (e.g., honey [26,[30][31][32][33][34][35], milk [34][35][36][37][38], meat [34,35,[39][40][41][42][43], seafood [44,45], and eggs [34,46,47]), there are still problems that need to be solved more or less. For example, a sample clean-up step, usually SPE, is typically required to eliminate matrix effects.…”