We have developed an optical sensor platform that might fulfil the requirements of the ideal breath analysing device.Breath analysis is emerging as a valuable noninvasive clinical diagnostic tool. As an example, the detection of an elevated concentration of ammonia in human breath has the potential to probe kidney and liver malfunctions. The ideal breath monitoring device is one that is sensitive to the specific gas and capable of accurately detecting it at physiologically relevant concentrations in the ppb range, insensitive to interferences, can simultaneously measure multiple VOCs at different concentration levels, is portable and easy to use for point-of-care, displays real-time data and is low cost.The innovation of our idea is that we combine silicon photonics with a high surface area chemically selectivecoating to enable these requirements. Silicon photonics integrates optical components. Extreme miniaturisation, dense integration and high accuracy at low cost for optical applications are the key features of this technology. By coating miniature optical silicon photonics resonators with a microporous chemically selective silica film, we paved the way for sensitive, compact and inexpensive gas sensors. We have elaborated this idea for ammonia gas detection and have demonstrated that the detection is sensitive, selective, real-time and reversible. Here, we'll develop the essential conditions to start the early commercial stage to market a breath analyser.