Polymeric sensors containing P-dimethylaminocinnamaldehyde: Colorimetric detection of urea nitrate

Abstract Identifying urea nitrate (UN) in post-blast debris is difficult, since it readily decomposes under high temperature. The authors developed onsite, rapid, and accurate detection of UN, using p -dimethylaminocinnamaldehyde ( p -DMAC) dispersed in poly(acrylamide) hydrogels. These hydrogels change color (yellow to red) upon exposure to UN in a concentration as low as 2 ppm. The p -DMAC-hydrogel system is sensitive to both UN solid and solution. This method can be easily applied for onsite detection of UN.