Analysis of Free Amino Acid Composition and Honey Plant Species in Seven Honey Species in China.

Honey is well-known as a food product that is rich in active ingredients and is very popular among consumers. Free amino acids (FAAs) are one of the important nutritional components of honey, which can be used not only as a nutritional indicator of honey but also as an indicator of plant source identification. In this study, the contents of 20 FAAs in seven types of honey from 11 provinces in China were examined for the first time.

Occurrence of organotin compounds in food: increasing challenge of phenyltin compounds.

Concentrations and distribution for 16 organotin compounds were studied in all kinds of foods, including seafood, agricultural products, and wine. Meanwhile, the degradation of the TBT or TPhT was also evaluated. Concentrations of total organotins in seafood, agricultural products, and wine were 1047.

Simultaneous qualitative and quantitative analyses of volatile components in Chinese honey of six botanical origins using headspace solid-phase microextraction and gas chromatography-mass spectrometry.

Background: Honey aroma is one of its most important properties and it depends on the qualitative and quantitative composition of the volatile compounds. The volatile profile of honey could reveal its botanical origin to avoid a false characterization. Thus, it is of great significance to honey authentication.

Simultaneous determination of cyanide and thiocyanate in milk by GC-MS/MS using cetyltrimethylammonium bromide as both phase transfer catalyst and protein precipitant.

A method was developed for simultaneous determination of cyanide and thiocyanate in milk by gas chromatography-tandem quadrupole mass spectrometry (GC-MS/MS). Cyanide and thiocyanate were derivatized with pentafluorobenzyl bromide (PFBBr) as PFB-CN and PFB-SCN, respectively. Cetyltrimethylammonium bromide (CTAB) was employed both as a phase transfer catalyst and a protein precipitant in the sample pretreatment, which facilitates the separation of the organic and aqueous phases, and greatly simplifies the pretreatment procedures to achieve simultaneous and rapid determination of cyanide and thiocyanate.

Comprehensive investigation of the content and the origin of matrine-type alkaloids in Chinese honeys.

A HPLC-MS/MS method for simultaneous determination of four matrine-type alkaloids (matrine, oxymatrine, sophocarpine and sophoridine) in honey was established and was applied to 567 Chinese honey samples. The overall detection rate was 61.0 % and all eight Sophora viciifolia Hance honey samples were detected with the average content of 1183.

Simultaneous determination of seven perfluoroalkyl carboxylic acids in water samples by 2,3,4,5,6-pentafluorobenzyl bromide derivatization and gas chromatography-mass spectrometry.

A new derivatization reagent, 2,3,4,5,6-pentafluorobenzyl bromide (PFBBr), was employed to determine seven perfluoroalkyl carboxylic acids (PFCAs) simultaneously in tap water with gas chromatography-mass spectrometry (GC-MS) technique in this study. Firstly, seven PFCAs were derivatized to their corresponding esters under alkaline condition. The derivatization conditions including the amount of PFBBr and KCO, derivatization temperature and time were optimized to increase the derivatization efficiency.

Simultaneous determination of nine perfluoroalkyl carboxylic acids by a series of amide acetals derivatization and gas chromatography tandem mass spectrometry.

A novel and simple derivatization method using a series of amide acetals as derivatization reagents, along with gas chromatography tandem mass spectrometry (GC-MS/MS) analysis, were developed and validated for simultaneous determination of 9 perfluoroalkyl carboxylic acids (PFCAs) in this study. The structures and fragmentation pathway of PFCAs derivatives were deduced and verified. The derivatization method developed in this study improved the sensitivity of the detection of PFCAs by GC.

Novel polyclonal antibody-based rapid gold sandwich immunochromatographic strip for detecting the major royal jelly protein 1 (MRJP1) in honey.

Honey adulteration is becoming increasingly alarming incidents in food safety. Monitoring and detecting adulteration face greater challenges. Honey contains the major royal jelly proteins (MRJP) secreted by bee workers.

Comprehensive determination of polycyclic aromatic hydrocarbons in Chinese herbal medicines by solid phase extraction and gas chromatography coupled to tandem mass spectrometry.

A simple and highly sensitive gas chromatography-tandem mass spectrometry (GC-MS/MS) method combined with solid-phase extraction cleanup was established for the comprehensive determination of 16 Environmental Protection Agency (EPA) polycyclic aromatic hydrocarbons (PAHs) in various kinds of Chinese herbal medicines (CHMs). A solid-phase extraction (SPE) purification strategy, including three parallel procedures, was developed depending on sample type, and satisfactory purification performances were achieved for all selected CHMs. The limits of detection ranged from 0.

[Simultaneous determination of cyhexatin, triphenyltin and fenbutatin oxide residues in fruits and vegetables by Grignard derivatization and gas chromatography coupled to tandem mass spectrometry].

A method for the simultaneous determination of cyhexatin, triphenyltin and fenbutatin oxide residues in fruits and vegetables was developed by Grignard derivatization and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). The samples were firstly digested by HC1/THF (1 :10, v/v), then extracted by hexane and followed by the derivatization with Grignard reagent (EtMgBr). Then after purification using florisil SPE columns, the sample extracts were finally analyzed by GC-MS/MS.

Determination of methyltin compounds in urine of occupationally exposed and general population by in situ ethylation and headspace SPME coupled with GC-FPD.

A method for the determination of methyltin compounds in human urine samples was developed using headspace solid-phase microextration (HS-SPME) coupled with gas chromatographic separation and flame photometric detection. Three methyltin compounds, monomethyltin (MMT), dimethyltin (DMT), and trimethyltin (TMT) were in situ ethylated by sodium tetraethylborate (NaBEt(4)) for SPME and GC-FPD analysis. Under the optimized condition, the detection limits of MMT, DMT, and TMT were 8.