Determination of 18 photoinitiators in food paper packaging materials by FastPrep-based extraction combined with GC-MS.

Extraction of photoinitiators (PIs) from food paper packages is difficult since they normally hide inside multiple ink layers. A one-step FastPrep-based extraction in combination with GC-MS was developed to simultaneously measure 18 PIs in food paper packaging materials. FastPrep-based extraction enabled direct and efficient release of PIs from raw paperboard in a minute without additional procedures. It was simple, high-throughput, consuming less solvent and not requiring heat or radiation. GC-MS using selected ion monitoring provided identification of PIs with high selectivity. The LODs and LOQs for 18 PIs ranged from 0.060 to 0.614 mg/kg, and 0.197-2.027 mg/kg, respectively. The method was successfully applied for various real samples, and the spiked recoveries using different real sample matrices ranged from 93.3% to 110.1%. The developed method can thus be used for the quality control of PI residues in paper packaging materials of food products.

[Effect of menthol cigarette on rats for metabonomics by liquid chromatography-mass spectrometry].

A liquid chromatography-mass spectrometry (LC-MS) method was developed for the metabonomics study of menthol cigarette effect on rats. Urines from three groups of rats were analyzed, including control rats, rats treated with menthol cigarette and rats treated with normal cigarette, and the data were processed by the method of principal component analysis (PCA). The PCA score plot showed that the metabolic difference between the rats treated with menthol cigarette and the control rats was smaller than that between the rats treated with normal cigarette and the control rats. Based on the PCA score plot, eight important metabolites, for example, kynurenic acid, were found and identified. Their relative concentration changes among the three groups further indicated that menthol cigarette maybe decrease the metabolic effect on rats.