I am trying to replicate the reaction that occurs with endotracheal tube colorimetric CO2 indicators where, upon exposure to exhaled CO2 a paper turns from purple to yellow. I know commercial devices use m-cresolsulfonphthalein (m-cresol purple) as the indicator. What type of paper best facilitates the reaction? Do I need to use ph paper soaked in m-cresol purple to facilitate the purple to yellow color change that occurs with exposure to exhaled CO2 at 37C?
The concentration of m-cresol purple in the indicator solution, as well as the thickness of the indicator paper, can affect the sensitivity and response time of your CO2 indicator. You may need to experiment with different concentrations and paper thicknesses to achieve the desired results. This DIY approach is a basic demonstration of the concept. Commercial CO2 detection devices use more advanced materials and engineering for accurate and consistent results.
Remember to exercise caution and work in a well-ventilated area when handling chemicals, and consider safety guidelines and regulations when working on projects like this.