Towards analytical stripes for detection of iron III cations in domestic water using proteinic biopolymers

Two renewable proteinic biopolymers; namely keratin and sericin, were blended, each separately, with poly acrylonitrile (PAN) as a supporter for film formation. The said protein/PAN composite was reacted with potassium thiocyanate in a way which directs the reaction away from thiohydnation mechanism. The resulted proteinium thiocyanate salt was utilized in detection of iron III ion in water through formation of the colored iron III thiocyanate complex which can be detected calorimetrically. The obtained colour depends on the concentration of iron III ion in the tested water sample. Results of this investigation proved that the said protein/PAN composite is an appropriate candidate for detection of iron III ion in water. The mode of interaction between the starting materials after being processed with PAN was monitored by using amino acid analysis, infrared spectroscopy, mass spectrometry, gel electrophoresis, and protein content. Scanning electron microscopy was used to study the surface characteristics of keratin/PAN/KSCN and sericin/PAN/KSCN films as well as their cross sections.