title: A microdevice for rapid optical detection of magnetically captured rare blood pathogens.
abstract: Sepsis diagnosis requires development of methods to identify rare pathogen cells in small samples of human blood. Magnetic beads functionalized with pathogen-binding ligands have been used to rapidly isolate microbes from blood; however, it is commonly difficult to optically detect the captured species because the excess numbers of beads required for pathogen binding physically interfere with light transmission after they have been concentrated. Here we describe a microdevice that uses microfluidics combined with optimized magnetic field concentrators and magnetic beads coated with a generic blood opsonin to efficiently capture unknown blood pathogens and spread them into a thin layer suitable for automated optical detection. Using this device, we have been able to detect fungal pathogens in less than three hours after sample collection compared to days with current technology, and with an extremely high sensitivity (<1 cell mL(-1) of human blood).
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, CLSB 517, Boston, MA 02118, USA. don.ingber@wyss.harvard.edu.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Cooper
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Leslie
authors.forename: Karel
authors.initials: K
authors.lastname: Domansky
authors.forename: Abhishek
authors.initials: A
authors.lastname: Jain
authors.forename: Chong
authors.initials: C
authors.lastname: Yung
authors.forename: Michael
authors.initials: M
authors.lastname: Cho
authors.forename: Sam
authors.initials: S
authors.lastname: Workman
authors.forename: Michael
authors.initials: M
authors.lastname: Super
authors.forename: Donald E
authors.initials: DE
authors.lastname: Ingber
mesh_terms: D002176:Candida albicans / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D018189:Immunomagnetic Separation / Q000295:instrumentation / Q000379:methods*; D008024:Ligands; D008280:Magnetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D018805:Sepsis / Q000175:diagnosis / Q000382:microbiology
chemical_list: D008024:Ligands