title: Specific detection of avidin-biotin binding using liquid crystal droplets.
abstract: Poly(acrylicacid-b-4-cynobiphenyl-4'-undecylacrylate) (PAA-b-LCP)-functionalized 4-cyano-4'-pentylbiphenyl (5CB) droplets were made by using microfluidic technique. The PAA chains on the 5CB droplets, were biotinylated, and used to specifically detect avidin-biotin binding at the 5CB/aqueous interface. The avidin-biotin binding was characterized by the configurational change (from radial to bipolar) of the 5CB droplets, as observed through a polarized optical microscope. The maximum biotinylation was obtained by injecting a >100 μg/mL biotin aqueous solution, which enabled a limit of detection of 0.5 μg/mL avidin. This droplet biosensor could specifically detect avidin against other proteins such as bovine serum albumin, lysozyme, hemoglobin, and chymotrypsinogen solutions. Avidin detection with 5CBPAA-biotin droplets having high sensitivity, specificity, and stability demonstrates new applications of the functionalized liquid crystal droplets that can detect specific proteins or other analytes through a ligand/receptor model.
authors.affiliation: School of Applied Chemical Engineering, Department of Polymer Science and Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Mashooq
authors.initials: M
authors.lastname: Khan
authors.affiliation: School of Applied Chemical Engineering, Department of Polymer Science and Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address: psy@knu.ac.kr.
authors.forename: Soo-Young
authors.initials: SY
authors.lastname: Park
mesh_terms: D000818:Animals; D001360:Avidin / Q000378:metabolism*; D001710:Biotin / Q000378:metabolism*; D019921:Biotinylation; D001713:Biphenyl Compounds / Q000737:chemistry; D002417:Cattle; D005453:Fluorescence; D050866:Liquid Crystals / Q000737:chemistry*; D044085:Microfluidics; D008853:Microscopy; D009570:Nitriles / Q000737:chemistry; D061848:Optical Imaging; D011485:Protein Binding; D012996:Solutions
chemical_list: D001713:Biphenyl Compounds; D009570:Nitriles; D012996:Solutions; D001360:Avidin; C433919:4-cyano-4'-pentylbiphenyl; D001710:Biotin
keywords: Avidin; Biosensor; Biotin; Liquid crystal droplet; Microfluidics; Selective biosensor