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. According to the time dependent IC50 values, the CIB could provide dynamic information that can be used to identify maximum toxicity of cigarette smoke and reversibility of the toxic effects which are difficult to achieve by the endpoint assays. The comparative IC50 values indicated that the as-developed biosensor offered analytical results in good consistency with the commonly used NRU method. The features of the CIB-based cytotoxicity assay, such as no cell labeling, automatic detection, and easy operation, give this assay potential to become routine setting for evaluating the cytotoxicity of CSCs.

[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 0.999 4 and the precision of measurement ranges from 1.3% to 9.5% in terms of relative standard deviation (n = 5). The recoveries for the cigarette flavour samples and the limits of detection are in the range of 88.1%-109.3% and 0.003-0.13 microg x L(-1), respectively. The results of experiment show that the method can meet the requirements of trace analysis. Thirty eight cigarette flavours from different cigarette manufacturing enterprises were determined. The results indicate that: (1) the contents of Be, Tl, Mo, Cd, V, Pb and As in cigarette flavours are very lower, the average values of which are all lower than 0.1 microg x g(-1). The content levels of Mn, Zn and Sr in cigarette flavours are higher, and that of other 4 elements are moderate. (2) The content difference of Mn, Cd and Sr in different cigarette flavours is usually bigger, the coefficients of variation of which are 276.4%, 238.7% and 243.8%, respectively.