Rapid determination of furosine in milk using microwave-assisted HCl hydrolysis and ultra-performance liquid chromatography

Research progress on metabolites of nitrofurazone in aquatic products

The carcinogenic and teratogenic risks of nitrofurazone (NFZ) led to its restriction in aquatic products. Semicarbazide (SEM), one of its metabolites, is a primary focus of modern monitoring techniques. However, the SEM residue in aquatic products is believed to be formed through endogenous mechanisms, especially for aquatic crustaceans. In this article, we will discuss the source of SEM, including its usage as an antibiotic in aquatic products (nitrofurazone), its production during food processing (azodicarbonamide and hypochlorite treatment), its occurrence naturally in the body, and its intake from the environment. SEM detection techniques were divided into three groups: derivatization, extraction/purification, and analytical methods. Applications based on liquid chromatography and its tandem mass spectrometry, immunoassay, and electrochemical methods were outlined, as were the use of various derivatives and their assisted derivatization, as well as extraction and purification techniques based on liquid-liquid extraction and solid-phase extraction. The difficulties of implementing SEM for nitrofurazone monitoring in aquatic products from crustaceans are also discussed. Possible new markers and methods for detecting them are discussed. Finally, the present research on monitoring illicit nitrofurazone usage through its metabolites is summarised, and potential problems that need to be overcome by continuing research are proposed with an eye toward giving references for future studies.

Assay of honey freshness by a novel optical technique

Assay of Maillard reaction products (e.g. furosine) is a reputable method for determination of the honey freshness. In this report, novel optical technique is proposed for real-time measurement of the changes of furosine content in honey. The method is based on the unidirectional energy transfer between two peaks of the doubled-peak fluorescence spectrum as secondary inner filter effect (2nd-IFE) in a specific arrangement of the laser induced fluorescence (LIF) setup. Proper optical parameters are defined accordingly, and affirmed to be dependent on the content of furosine in honey. It is shown that the introduced parameters are not sensitive to the LIF intensity fluctuations induced by the ambient noises and particularly alter due to the 2nd-IFE. Furosine level of 8 honey types with different botanical origin were chemically determined before and after the 1 year storage, and compared with the values of the devised spectral parameters. Proofs conducted that the proposed technique can be utilized for evaluation of the honey freshness.