High-sensitivity detection of oxytetracycline using light scattering agglutination assay with aptasensor.
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.
Kim
Keesung
K
School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea.
Gu
Man-Bock
MB
Kang
Do-Hyun
DH
Park
Jee-Won
JW
Song
In-Hong
IH
Jung
Ho-Sup
HS
Suh
Kahp-Yang
KY
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
D052157:Aptamers, Nucleotide; D011137:Polystyrenes; D010118:Oxytetracycline