title: Magnetophoretic Transport Line System for Rapid On-Chip Attomole Protein Detection.
abstract: A lab-on-a-chip traveling wave magnetophoresis approach for sensitive and rapid protein detection is reported. In this method, a chip-based magnetic microarray comprising lines of micrometer-sized thin film magnetic elements was used to control the movement of magnetic beads (MBs). The MBs and the chip were functionalized, forming a sandwich-type assay. The MBs were transported across a detection area, and the presence of target molecules resulted in the immobilization of MBs within this area. Target quantification was accomplished by MB counting in the detection area using an optical microscope. In order to demonstrate the versatility of the microarray, biotinylated antiavidin was selected as the target protein. In this case, avidin-functionalized MBs and an avidin-functionalized detection area were used. With a total assay time of 1 to 1.5 h (depending on the labeling approach used), a limit of detection in the attomole range was achieved. Compared to on-chip surface plasmon resonance biodetection systems, our method has a larger dynamic range and is about a factor of 500 times more sensitive. Furthermore, our MB transportation system can operate in any chip-based biosensor platform, thereby significantly improving traditional biosensors.
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Rebecca S
authors: RS
authors: Bejhed
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Bo
authors: B
authors: Tian
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Kristofer
authors: K
authors: Eriksson
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Rimantas
authors: R
authors: Brucas
authors: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden.
authors: Sven
authors: S
authors: Oscarsson
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Mattias
authors: M
authors: Strömberg
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Peter
authors: P
authors: Svedlindh
authors: Department of Engineering Sciences, Division of Solid State Physics, The Ångström Laboratory, Uppsala University , Box 534, SE-751 21 Uppsala, Sweden.
authors: Klas
authors: K
authors: Gunnarsson
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D040081:Protein Array Analysis; D011506:Proteins / Q000032:analysis / Q000737:chemistry*
chemical_list: D011506:Proteins