Accuracy and speed are two important arguments when it comes to determination of quality parameters in e-liquids for e-cigarettes. Metrohm has published three new Applications Notes (AN) describing the determination of nicotine, glycerin, and water in these liquid mixtures. All three methods are time-saving and reliable solutions.
Electronic cigarettes are alternatives to conventional tobacco cigarettes. They are growing constantly in popularity. E-cigarettes are handheld devices that heat and vaporize a solution called e-liquid to simulate the feeling of smoking. The liquid usually consists of propylene glycol, glycerol, flavors, and nicotine.
For the e-cigarette market it is to be expected that stricter labeling rules relating to details about e-liquid ingredients have to be observed in the future. For this reason, fast analysis methods of quality parameters such as nicotine, glycerin, and water in e-liquids are trendsetting and already required.
A very suitable solution is the use of visible near-infrared spectroscopy (NIRS), which enables simultaneous real-time quantification of nicotine and glycerin without sample preparation. Another method to determine nicotine is potentiometric titration. Nicotine in tobacco is usually measured by gas chromatography or liquid chromatography. Acid base titration is a much more affordable alternative.
Another important quality parameter in this field is water or moisture content of e-liquids. In this case Karl Fischer titration (KFT) is the method of choice because KFT is specific for water and the result is not falsified by other volatile substances.