A rapid, automated method for the simultaneous quantitative analysis of nicotine and water in the condensate of tobacco smoke was developed. With the process, it is also possible to quantify the propylene glycol and diethylene glycol, as well as the triacetin contents of the condensate. The apparatus comprises an isotherm gas chromatograph with an automatic injector. A variable split is connected to the injector block, which distributes the sample between two separation columns, as analysis of all substances in a single column does not succeed in a short time. The signals of the two detectors used (thermal conductivity detector and flame ionisation detector) are transferred one after another, time-switched, to an electronic single-channel integrator to be evaluated. With the system described, up to sixty analyses a day are made possible.
To supplement known gas chromatographic processes for determining the residues of the aldicarb pesticide in tobacco, we have developed a method which makes use of high-pressure liquid chromatography. This is of particular importance inasmuch as the German Law on Pesticides provides for a maximum amount of aldicarb in tobacco.
Our investigations show that pulsed nuclear magnetic resonance spectroscopy (p-NMR) is a suitable method of determining the triacetin content of freshly produced filter rods. The table-top pulse spectrometer tested in filter rod production distinguishes itself by the fact that it enables exact and reproducible direct measurements of whole filter rods to be made in seconds. There is no need for the whole process of preparing samples; after measurement the filters can be fed back into the production process. With the measuring method we have developed triacetin can be determined completely automatically, independent of sample weight and to a large extent independent of the moisture content of the filter material. The period of time between the triacetin application and the p-NMR measurement should be as short as possible and accurately reproducible.
Watery tobacco extracts were examined with the aid of flow-injection analysis (FIA) for the substances nicotine, nitrate, chloride, ammonium and phosphate. The results proved to be exact and reproducible for the most part and the speed of analysis was between 37 and 113 measurements per hour. Because of its simple modular design the appliance is flexible in its application and is above all suited for the analysis for several components in small series of samples. A special FIA technique (stopped-flow method) enables the undersurface absorption stemming from the sample matrix to be excluded. The solutions used must exhibit uniform fluid composition and the formation of gas bubbles in the analysis system must be excluded.