“…Prior to metal ion immobilization, the chelating agent needs to be bound to the membrane matrix. The common choices of chelating agents are multidentates, such as iminodiacetic acid, tridentate (IDA), nitrilotriacetic acid, tetradentate (NTA), and N,N,N-tris(carboxymethyl)ethylenediamine, pentadentate (TED) [ 1 , 5 , 13 , 14 , 16 , 32 , 33 ], as well as triazine dyes [ 3 , 5 , 34 , 35 , 36 ]. Nevertheless, the direct coupling of a chelating agent onto a polymeric membrane matrix is not usually easy.…”