Physical amplification of chemical colorimetric sensing

Rapid and sensitive detection of hazardous chemicals is essential for worker safety in industrial environments and for soldier safety in the field. In this work, we propose a physical coloration platform to passively amplify existing colorimetric sensing mechanisms. We outline a design process which can be targeted to an arbitrary colorimetric indicator and target and fabricate as a demonstration a sensor which produces noticeable color change on reaction with ammonia in the vapor phase.