Interference-free detection of trace copper in the presence of EDTA and other metals using two complementary chelating polymers

► Interference-free copper detection in water and wastewater at trace level. ► No other existing technique can achieve it in the presence of EDTA. ► Unique chemistry of two reusable chelating polymers forms the heart of the process. ► The sensing technique is robust and easy to apply. ► Technique can be applied in the absence of instruments.