title: High-sensitivity detection of oxytetracycline using light scattering agglutination assay with aptasensor.
abstract: We present an aptamer-based biosensor (aptasensor) for rapid and high-sensitive detection of oxytetracycline (OTC) antibiotic in PBS inside a Y-channel PDMS microfluidic device. The detection was made by real-time monitoring of the agglutination assay of ssDNA aptamer-conjugated polystyrene latex microspheres with proximity optical fibers. The agglutination assay was performed with serially diluted OTC antibiotic solutions using highly carboxylated polystyrene particles of 920 nm diameter conjugated with OTC-binding ssDNA aptamer. Proximity optical fibers were used to measure the increase in 45° forward light scattering of the aggregated particles by fixing them around the viewing cell of the device with stable angle and distance to the detector. The detection limit was around 100 ppb for the current aptasensor system with the detection time less than 3 min.
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea.
authors.forename: Keesung
authors.initials: K
authors.lastname: Kim
authors.forename: Man-Bock
authors.initials: MB
authors.lastname: Gu
authors.forename: Do-Hyun
authors.initials: DH
authors.lastname: Kang
authors.forename: Jee-Won
authors.initials: JW
authors.lastname: Park
authors.forename: In-Hong
authors.initials: IH
authors.lastname: Song
authors.forename: Ho-Sup
authors.initials: HS
authors.lastname: Jung
authors.forename: Kahp-Yang
authors.initials: KY
authors.lastname: Suh
mesh_terms: D000372:Agglutination Tests / Q000379:methods*; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D008027:Light; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D008853:Microscopy; D008863:Microspheres; D055100:Optical Fibers; D010118:Oxytetracycline / Q000032:analysis* / Q000378:metabolism; D011137:Polystyrenes; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity
chemical_list: D052157:Aptamers, Nucleotide; D011137:Polystyrenes; D010118:Oxytetracycline