Enhanced Electrochemical Detection of Heavy Metal Ions Using TPyP-sPEEK Composite-Modified Electrodes

Porphyrin/sulphonated polyetheretherketone (sPEEK) composites are successfully obtained at different dye/polymer weight/weight percentage taking advantage of electrostatic interactions among the protonable nitrogen atoms of 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin porphyrin (TPyP) and anionic sulphonated groups of the polymer with 65% of sulfonation degree. These supramolecular adducts(TPyP-sPEEK) are drop-casted onto a commercial screen-printed carbon substrate (SPCE) to fabricate new modified TPyP-sPEEK /SPCE sensors for the detection of heavy metal ions such as Pb2+, Cd2+, and Hg2+. Sample at different porphyrin loads has been analyzed by electrochemical techniques. sPEEK composite with 5% porphyrin/polymer w/w% is identified as the optimal one in terms of stability and high percentages of recovery of the tested heavy metal ions in seawater environment.