EDTA Chelates play important roles in oxygen transport and photosynthesis. Furthermore, many biological catalysts (enzymes) are chelates. In addition to their significance in living organisms, chelates are also economically important, both as products in themselves and as agents in the production of other chemicals. LidoChem, Inc. has a full line of chelates – Including CaEDTA, CuEDTA, FeEDTA, FeEDDHA – 80% and 50% Ortho and ZnEDTA.