dibutyl phthalate (dbp) is a phthalic acid ester and is widely used in polymeric products to make them more flexible. dbp is found in almost every plastic material and is believed to be persistent in the environment. various analytical methods have been used to measure dbp in different matrices. considering the ubiquitous nature of dbp, the most important challenge in dbp analyses is the contam...

cucumber is one of the main vegetables in iranian food basket. a wide range of pesticides are used for crops protection during the cultivation of vegetables such as cucumber due to heavy pest infestation. analysis of pesticide residues in food and other environmental commodities have become essential requirement for consumers, producers, and food quality control authorities. this study was aime...

the chemical composition of the hydrolate of citrus aurantium l. (rutaceae) flowers (neroli) grown in iran, and two commercial hydrolates were analyzed by gc/ms. thirty compounds (90.3%) were identified in the hydrolate by the use of laboratory apparatus, thirty-eight compounds (83.4%) in the hydrolate from the traditional method and fifteen compounds (98.3%) in the industrially produced sample...

a fast and simple modified quechers extraction method was developed for determination of benzo[a]pyrene (bap) in 137 traditional (sangak), semi-industrial (sangak) and industrial bread samples using spiked calibration curves by gc/ms. sample preparation includes extraction of bap into acetone followed by cleanup with dispersive solid phase extraction. the limit of detection and limit of quantif...

A new approach of flow modulation comprehensive two-dimensional gas chromatography-mass spectrometry (GC x GC-MS) with supersonic molecular beam (SMB) and a quadrupole mass analyzer is presented. Flow modulation uniquely enables GC x GC-MS to be achieved even with the limited scan speed of quadrupole MS, and its 20 ml/min column flow rate is handled, splitless, by the SMB interface. Flow modula...

Fluxome analysis aims at the quantitative analysis of in vivo carbon fluxes in metabolic networks, i. e. intracellular activities of enzymes and pathways. It allows investigating the effects of genetic or environmental modifications and thus precisely provides a global perspective on the integrated genetic and metabolic regulation within the intact metabolic network. The experimental and comput...

The applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to screening for 140 pesticides in agricultural products was examined. Validation of multi-residue screening methods for the determination of 88 pesticides in 12 crops (asparagus, cauliflower, burdock, carrot, broccoli, spinach, matsutake mushroom, orange, soybean, sesame, millet and tea) was done ...