Separation and quantitation of three acidic herbicide residues in tobacco and soil by dispersive solid-phase extraction and UPLC-MS/MS.

A method for the determination of three acidic herbicides, dicamba, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) in tobacco and soil has been developed based on the use of liquid-liquid extraction and dispersive solid-phase extraction (dispersive-SPE) followed by UPLC-MS/MS. Two percentage of (v/v) formic acid in acetonitrile as the extraction helped partitioning of analytes into the acetonitrile phase. The extract was then cleaned up by dispersive-SPE using primary secondary amine as selective sorbents.

Evaluation of the cytotoxicity of cigarette smoke condensate by a cellular impedance biosensor.

In this study, a cytotoxicity assay was developed for profiling the cytotoxicity of cigarette smoke condensates (CSCs) base on a cellular impedance biosensor (CIB). Compared with the traditional in vitro cytotoxicity assays, this CIB-based method offered distinct advantages in real-time kinetic measurement which provided a comprehensive understanding of cellular responses for the entire duration of the experiment and prediction of the potential mechanism of action of a given treatment. The time-dependent cell response profiles provided valid evidences for optimization of cell number per well, cell quality control, and identification of the optimal time points for compound treatment and endpoint assays.

[Determination of trace elements in cigarette flavours by closed-vessel microwave digestion-inductively coupled plasma mass spectrometry].

Tobacco flavours have great effect on the aroma, taste and quality stabilization of cigarettes. In order to effectively control the quality of cigarette flavours and reduce the content level of toxic elements in cigarette mainstream smoke, a method for the simultaneous determination of Be, V, Cr, Mn, Ni, Cu, Zn, As, Se, Sr, Mo, Cd, Tl and Pb in cigarette flavours by inductively coupled plasma mass spectrometry (ICP-MS) with closed-vessel microwave assisted digestion was developed. The linear correlative coefficients for all elements are better than 0.