Solid phase microextraction of volatile organic compounds from cigarette smoke

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The determination of volatile compounds in gas samples is a challenging issue. Firstly, because it is difficult to collect large and representative samples and secondly due to the potential losses of the analyte by diffusion through the pores of the sample container. Moreover, the mandatory preconcentration step that must be implemented prior to the instrumental analysis must be carried out maintaining the sample homogeneity.

From the Centers for Disease Control and Prevention in Atlanta, we can read a very interesting approach for the simultaneous determination of up to 22 volatile organic compounds (VOCs) present in cigarette smoke (1). In addition to their elegant approach to overcome the previously mentioned difficulties, they are able to quantify a broad range of smoke VOCs, usually measured by separated assays. It should also be noticed that all the samples (cigarette smokes) were generated following the ISO3308:2000 standard which assure the validity of the results in terms of compounds to be detected and also their concentration. This fact is crucial for comparison purposes.

The authors propose the use of 1 L polyvinyl fluoride sampling bags which are directly connected to the smoking machine. After collection, the bags are heated at 50 ºC for homogenization purposes. Then, 15 bags were placed on a dedicated bag tray where a 75 µm carboxen-PDMS SPME fiber was introduced through the bag injection port to isolate and preconcentrate the target compounds during 1 min. Particulate-phase sample were collected in headspace vials and analyzed using the same SPME phase.

The article discusses in depth relevant aspects related to automation, standard preparation and calibration, analyte-specific biases as well as the basic analytical properties of the analytical approach.

We encourage our readers to go through the proposed research article which in addition to the excellent analytical approach, deals with a social problem of the highest priority as they develop a new tool capable of evaluating the exposure of active and passive smokers to such compounds indentified as carcinogenic.

References:

(1) Simultaneous analysis of 22 volatile organic compounds in cigarette smoke using gas sampling bags for high-throughput SPME. Link to the article

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