Bioapplications of Polythiophene-g-Polyphenylalanine-Covered Surfaces

The fabrication of electro and bioactive surfaces by electrochemical deposition of the thiophene-functionalized polyphenylalanine macromonomer (T-g-PPhe) is reported. The resulting conducting graft copolymer, polythiophene-graft-polyphenylalanine (PT-g-PPhe) formed on the indium tin oxide (ITO) glass surface, is characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and fluorescence microscopy. Then, possible uses of PT-g-PPhe as matrices in the sensor design for both electrochemical biosensing and cell adhesion studies are investigated. In the first part, PT-g-PPhe that is deposited on ITO is further functionalized with the arginylglycylaspartic acid peptide via 1-Ethyl-3-(3 dimethylaminopropyl) carbodiimide for the selective cell adhesion. Immunofluorescence staining is performed to detect the difference between adherences of 'integrin alpha v beta 3' receptor positive (U87-MG) and negative (HaCaT) cell lines on to the biofunctional surface. In the second part, an electrochemical glucose sensor is constructed by immobilizing glucose oxidase on the surface of PT-g-PPhe, which is deposited on a glassy carbon electrode.