title: Seed particle-enabled acoustic trapping of bacteria and nanoparticles in continuous flow systems.
abstract: Acoustic trapping of sub-micron particles can allow enrichment and purification of small-sized and low-abundance microorganisms. In this paper, we investigate the dependency of the ability to capture sub-micron particles on the particle concentration. Based on the findings, it is demonstrated that seed particles can be introduced to acoustic trapping, to enable capture of low-abundance sub-micron particles. Without using seed particles, continuous enrichment of 490 nm polystyrene particles is demonstrated in a rectangular capillary with a locally generated acoustic field at high particle concentrations, i.e. above 1% wt. Trapping of sub-micron particles at significantly lower concentrations was subsequently accomplished by seeding 10-12 micrometer-sized particles in the acoustic trap prior to the sub-micron particle capture. Furthermore, the new seeded-particle-aided acoustic trapping technique was employed for the continuous enrichment of bacteria (E. coli) with a capture efficiency of 95%. Finally, seed particle assisted acoustic trapping and enrichment is demonstrated for polymer-based particles down to 110 nm in diameter.
authors.affiliation: Department of Measurement Technology and Industrial Electrical Engineering, Lund University, Sweden. Bjorn.Hammarstrom@elmat.lth.se
authors.forename: Björn
authors.initials: B
authors.lastname: Hammarström
authors.forename: Thomas
authors.initials: T
authors.lastname: Laurell
authors.forename: Johan
authors.initials: J
authors.lastname: Nilsson
mesh_terms: D000162:Acoustics / Q000295:instrumentation; D004926:Escherichia coli / Q000737:chemistry* / Q000302:isolation & purification*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry
chemical_list: D011137:Polystyrenes