title: Measuring ligand-receptor binding events on polymeric surfaces with periodic wave patterns using liquid crystals.
abstract: In this study, we measured ligand-receptor binding events on polymeric substrates with periodic nanostructures using liquid crystals (LCs). Periodic sinusoidal wave patterns were generated through the buckling of the poly-(dimethylsiloxane) (PDMS) substrate on a cylindrical surface followed by replicating the associated relief structures on a poly-(urethane acrylate) (PUA) surface, where a film of gold was deposited. Avidin was then covalently immobilized onto a gold surface decorated with carboxylic acid-terminated self-assembled monolayer via NHS/EDC chemistry. The optical response of the device showed that the orientation of nematic 4-cyano-4'-pentylbiphenyl (5CB) was parallel to the plane of the avidin surface. However, the formation of the avidin-biotin complexes disturbed the sinusoidal topographies of the surface, and induced a random orientation of LCs, which produced a distinctive change in the optical response. We also confirmed the specific ligand-receptor interactions using ellipsometry and atomic force microscopy (AFM). These results suggest that polymeric surfaces with continuous wavy features could be used to develop novel LC-based sensors for the detection of ligand-receptor binding events.
authors.affiliation: College of BioNano Technology, Kyungwon University, Sujeong-Gu, Seongnam-City, Gyeonggi-Do, Republic of Korea.
authors.forename: Gyeo-Re
authors.initials: GR
authors.lastname: Han
authors.forename: Chang-Hyun
authors.initials: CH
authors.lastname: Jang
mesh_terms: D001360:Avidin / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry; D001713:Biphenyl Compounds / Q000737:chemistry*; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D008024:Ligands; D050866:Liquid Crystals / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009570:Nitriles / Q000737:chemistry*; D055096:Optical Devices; D011140:Polyurethanes / Q000737:chemistry; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000032:analysis*; D013499:Surface Properties
chemical_list: D001713:Biphenyl Compounds; D004129:Dimethylpolysiloxanes; D008024:Ligands; D008689:Methacrylates; D009570:Nitriles; D011140:Polyurethanes; D011956:Receptors, Cell Surface; C097103:polyurethane dimethacrylate; D001360:Avidin; C433919:4-cyano-4'-pentylbiphenyl; C013830:baysilon; D001710:Biotin; D006046:Gold