methods , system and device are provided for detection and quantitative and qualitative analysis of components in a gaseous mixture distinguished by high selectivity and high resolution . the influence of individual gases may be distinguished through detection of changes associated with a sensor &# 39 ; s sensitive layer that interacts with the components of the gaseous mixture . through periodic variations of parameters or conditions of the sensor , the characteristics of the gas components may be derived . for example , the concentration of a gas or multiple gases in a mixture may be determined with a high degree of accuracy . non - invasive detection of biological off - gases may be implemented . other uses abound .