(220c) Innovative Approaches for Ammonia Detection on Paper Substrates

Ammonia (NH3) serves as a crucial commodity chemical in various industries, including fertilizer production, pharmaceuticals, textiles, and ammunition manufacturing. However, accurately quantifying ammonia concentrations remains challenging, often necessitating the use of expensive techniques such as nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC-MS). These methods, while sensitive, may struggle with detecting lower concentrations and incur high costs, limiting their accessibility. Here, we present a novel approach to ammonia quantification using a paper-based system. Leveraging the indophenol method, our technique substantially reduces reagent volume and solution quantities, thereby minimizing costs. Notably, the absence of a requirement for a UV-Vis spectrometer in the field setting enhances its practicality. Instead, analysis is simplified using Image J software, offering a user-friendly and cost-effective alternative. Our study systematically investigates the impact of reagent volume, sample volume, and time dependence on quantification accuracy, optimizing conditions for robust ammonia detection. To validate our method, we calibrated it against NMR and successfully quantified an unknown ammonia concentration. Overall, our paper-based approach offers a promising solution for affordable and reliable ammonia quantification, with potential applications in diverse industrial and environmental settings.