Diagnostic method for high sensitivity detection of component concentrations in human gas emission

A skin gas collection system, comprising:

• a collection chamber housing defining an interior space, the collection chamber housing having a gas inlet, a gas outlet, and an opening, the opening being configured for enclosing a skin portion from which to receive an emitted gas sample and sealing the interior space against the skin portion;
• an inert gas source connected to the gas inlet, the gas inlet configured for allowing inert gas from the inert gas source to flow into the interior space;
• a gas cell connected to the gas outlet, the gas outlet configured for allowing a mixture of the inert gas and the gas sample to flow from the interior space into the gas cell;
• a tunable optical radiation emitter configured for directing an optical radiation beam through the gas cell;
• a power detector for measuring one or more power signals of the optical radiation beam after the optical radiation beam passes through the gas cell;
• an acoustic microphone for measuring one or more optoacoustic signals from the gas cell as the optical radiation beam basses through the gas cell;
• and
• a concentration detection system for measuring a concentration of a specified component in the emitted gas sample based on the one or more power signals and the one or more optoacoustic signals.