?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F8462%2F&rft.title=INTERFACIAL+ELECTRON+TRANSFER+OF+CYTOCHROME+C+AND+CONJUGATED+POLYELECTROLYTE%2FSURFACTANT+COMPLEXES&rft.creator=Yue%2C+Hongjun&rft.description=Cytochrome+c+(cyt+c)+acts+as+an+electron+shuttle+in+biological+respiration+and+photosynthesis.+Although+the+understanding+of+this+protein+and+its+electron+transfer+(ET)+reaction+is+relatively+highly+developed%2C+many+of+its+aspects+remain+unclear.+We+use+supramolecular+assemblies+of+cytochrome+c+to+understand+its+ET+at+an+interface+in+terms+of+how+the+ET+depends+on+solution+composition%2C+SAM+composition%2C+temperature%2C+immobilization+methods+and+the+nature+of+the+electron+tunneling+pathway.+From+these+studies+we+have+learned%3A+(1)+the+formal+potential+and+the+surface+charge+of+cytochrome+c+are+modified+when+binding+to+a+negatively+charged+surface%3B+(2)+cytochrome+c+molecules+assume+a+wide+distribution+of+geometries+when+electrostatically+binding+to+a+negatively+charged+surface%2C+which+leads+to+a+wide+distribution+of+ET+rate+constants%3B+(3)+when+the+protein+is+within+14+%C3%85+of+the+electrode%2C+the+ET+rate+is+controlled+by+local+frictional+motions+rather+than+by+electron+tunneling%3B+(4)+the+binding-inactive+sites%2C+the+diluent+molecules+on+the+SAM+can+provide+alternative+electron+tunneling+pathways+from+electrode+surface+to+the+heme+of+cytochrome+c%2C+and+in+suitable+conditions+the+diluent+molecules+dominate+in+the+electron+tunneling+pathway.+Poly+(phenylethynylene)+(PPE)+based+conjugated+polyelectrolytes+are+a+class+of+polyions+having+rigid+backbones.+We+present+a+fluorescence+correlation+spectroscopy+(FCS)+study+on+the+hydrodynamic+properties+of+complexes+formed+by+two+PPE-SO3-+polymers%2C+having+different+charge+density%2C+with+octadecyl+trimethylammoniumbromide+(OTAB)+below+the+critical+micelle+concentration.+The+concentration+ratio+COTAB+%2FCmonomer+ranges+from+0.2+to+1800.+The+hydrodynamic+radius+of+the+complexes+as+a+function+of+OTAB+concentration+has+three+regimes.+In+the+low+concentration+regime%2C+the+complex+has+a+comparable+size+with+the+polymer+in+deionized+water.+In+the+intermediate+concentration+regime+the+complexes+have+the+largest+size+and+substantial+heterogeneity.+In+the+high+concentration+regime%2C+the+complexes+have+a+size+that+is+about+three+times+larger+than+that+in+the+low+concentration+regime.+The+results+significantly+extend+the+understanding+of+the+interaction+between+polyelectrolyte+and+ionic+surfactant%2C+and+indicate+that+the+rigidity+of+polymer+backbone+and+COTAB+%2FCmonomer+concentration+ratio+act+to+determine+the+composition+of+polyelectrolyte%2Fsurfactant+complexes.&rft.date=2007-09-27&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F8462%2F1%2FYUEHJETD2.pdf&rft.identifier=++Yue%2C+Hongjun++(2007)+INTERFACIAL+ELECTRON+TRANSFER+OF+CYTOCHROME+C+AND+CONJUGATED+POLYELECTROLYTE%2FSURFACTANT+COMPLEXES.++Doctoral+Dissertation%2C+University+of+Pittsburgh.++++(Unpublished)++