Electrochemical Characterization of Protein Adsorption onto YNGRT-Au and VLGXE-Au Surfaces.
The adsorption of the proteins CD13, mucin and bovine serum albumin on VLGXE-Au and YNGRT-Au interfaces was monitored by electrochemical impedance spectroscopy in the presence of [Fe(CN)6](3-/4-). The hydrophobicity of the Au surface was tailored using specific peptides, blocking agents and diluents. The combination of blocking agents (ethanolamine or n-butylamine) and diluents (hexanethiol or 2-mercaptoethanol) was used to prepare various peptide-modified Au surfaces. Protein adsorption onto the peptide-Au surfaces modified with the combination of n-butylamine and hexanethiol produced a dramatic decrease in the charge transfer resistance, Rct, for all three proteins. In contrast, polar peptide-surfaces induced a minimal change in Rct for all three proteins. Furthermore, an increase in Rct was observed with CD13 (an aminopeptidase overexpressed in certain cancers) in comparison to the other proteins when the VLGXE-Au surface was modified with n-butylamine as a blocking agent. The electrochemical data indicated that protein adsorption may be modulated by tailoring the peptide sequence on Au surfaces and that blocking agents and diluents play a key role in promoting or preventing protein adsorption. The peptide-Au platform may also be used for targeting cancer biomarkers with designer peptides.
Department of Chemistry, Oakland University, 2200 North Squirrel Road, Rochester, MI 48309, USA. htrzecia@oakland.edu.
Hanna
H
Trzeciakiewicz
Department of Chemistry, Oakland University, 2200 North Squirrel Road, Rochester, MI 48309, USA.
Jose
J
Esteves-Villanueva
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 87 Avenue, Edmonton, AB T6G 2E1, Canada. soudy@ualberta.ca.
Rania
R
Soudy
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 87 Avenue, Edmonton, AB T6G 2E1, Canada. kkaur@chapman.edu.|Chapman University School of Pharmacy, Harry and Diane Rinker Health Science Campus, Chapman University, Irvine, CA 92618-1908, USA. kkaur@chapman.edu.
Kamaljit
K
Kaur
Department of Chemistry, Oakland University, 2200 North Squirrel Road, Rochester, MI 48309, USA. martic@oakland.edu.
Sanela
S
Martic-Milne
D000327:Adsorption; D000818:Animals; D002417:Cattle; D017097:Electric Impedance; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D055767:Immobilized Proteins / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011485:Protein Binding; D012710:Serum Albumin, Bovine / Q000302:isolation & purification*; D012996:Solutions; D013499:Surface Properties
D055767:Immobilized Proteins; D010455:Peptides; D012996:Solutions; D012710:Serum Albumin, Bovine; D006046:Gold
CD13; electrochemistry; mucin; peptides