title: Detecting endotoxin with a flow cytometry-based magnetic aptasensor.
abstract: Endotoxin, which is also known as lipopolysaccharide (LPS), is a marker for intruding gram-negative pathogens. It is essential to detect endotoxin quickly and sensitively in a complex milieu. A new flow cytometry (FCM)-based magnetic aptasensor assay that employs two endotoxin-binding aptamers and magnetic beads has been developed to detect endotoxin. The endotoxin-conjugated sandwich complex on magnetic beads was observed by scanning confocal laser microscopy. The resulting magnetic aptasensor rapidly detected (<1 min) endotoxin within a broad dynamic detection range of 10(-8) to 10(0)mg/ml in the presence of bovine serum albumin (BSA), RNA, sucrose, and glucose, which are most likely to coexist with endotoxin in the majority of biological liquids. Only 2 μl of magnetic aptasensor was required to quantify the endotoxin solution. Furthermore, the magnetic aptasensor could be regenerated seven times and still presented an outstanding response to the endotoxin solution. Therefore, the magnetic aptasensor exhibited high sensitivity, selectivity, and reproducibility, thereby serving as a powerful tool for the quality control and high-throughput detection of endotoxin in the food and pharmaceutical industries.
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Zuo
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Chen
authors.affiliation: Hefei National Laboratory for Physical Science at the Microscale, Core Facility Center for Life Sciences, University of Science and Technology of China, Hefei 230027, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Tan
authors.affiliation: Hefei National Laboratory for Physical Science at the Microscale, Core Facility Center for Life Sciences, University of Science and Technology of China, Hefei 230027, People's Republic of China. Electronic address: lzf@ustc.edu.cn.
authors.forename: Zhao-Feng
authors.initials: ZF
authors.lastname: Luo
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Wang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation / Q000379:methods*; D004731:Endotoxins / Q000032:analysis* / Q000737:chemistry; D005434:Flow Cytometry; D005453:Fluorescence; D057230:Limit of Detection; D060328:Magnetic Phenomena; D015203:Reproducibility of Results
chemical_list: D052157:Aptamers, Nucleotide; D004731:Endotoxins
keywords: Aptasensor; Endotoxin; Flow cytometry; Magnetic beads