HovaCAL?—a generator for multi-component humid calibration gases

摘要

Process control, breath analysis for medical purpose or the investigation of biological samples are new applications of ion mobility spectrometry or differential mobility spectrometry coupled with rapid gas-chromatographic pre-separation. Especially if pre-concentration steps should be avoided, they require a realistic and flexible multi-compound calibration down to the pptV range including relative humidity values up to 100% for identification of analytes using mobility and retention time as well as for their quantification using the signal intensity as a measure. With HovaCAL® 3834SP-VOC, a novel calibration gas generator is presented that fulfils those requirements. The performance of HovaCAL® was validated for various compounds and mixtures with varying humidity comparing 3 particular equipments. Excellent results have been obtained with standard deviations of the provided concentrations of <8% and of <0.7% for the relative humidity range of 0–100%. Furthermore, standard deviation of the provided concentrations was <3% for varying experimental conditions. The long term stability of the provided concentrations for different instrumental parameters was proofed, standard deviations of <3% have been obtained. HovaCAL® enables for the first time a reliable calibration with complex humid mixtures down to the pptV range and—compared to permeation sources—a flexible and rapid change of compounds.