title: Rare-cell enrichment by a rapid, label-free, ultrasonic isopycnic technique for medical diagnostics.
abstract: One significant challenge in medical diagnostics lies in the development of label-free methods to separate different cells within complex biological samples. Here we demonstrate a generic, low-power ultrasonic separation technique, able to enrich different cell types based upon their physical properties. For malaria, we differentiate between infected and non-infected red blood cells in a fingerprick-sized drop of blood. We are able to achieve an enrichment of circulating cells infected by the ring stage of the parasite over nonparasitized red blood cells by between two and three orders of magnitude in less than 3 seconds (enabling detection at parasitemia levels as low as 0.0005%). In a second example, we also show that our methods can be used to enrich different cell types, concentrating Trypanosoma in blood at very low levels of infection, on disposable, low-cost chips.
authors.affiliation: Division of Biomedical Engineering, University of Glasgow, Glasgow, G12 8LT (UK).
authors.forename: Yannyk
authors.initials: Y
authors.lastname: Bourquin
authors.forename: Abeer
authors.initials: A
authors.lastname: Syed
authors.forename: Julien
authors.initials: J
authors.lastname: Reboud
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Ranford-Cartwright
authors.forename: Michael P
authors.initials: MP
authors.lastname: Barrett
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Cooper
mesh_terms: D002469:Cell Separation; D004912:Erythrocytes / Q000469:parasitology / Q000502:physiology*; D006801:Humans; D008288:Malaria / Q000175:diagnosis*; D010963:Plasmodium falciparum / Q000502:physiology; D011137:Polystyrenes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014345:Trypanosoma / Q000502:physiology; D014352:Trypanosomiasis / Q000175:diagnosis*; D014465:Ultrasonics
chemical_list: D011137:Polystyrenes; D012822:Silicon Dioxide
keywords: diagnostic; isopycnic gradient; malaria; surface acoustic waves