Isolation and concentration of bacteria from blood using microfluidic membraneless dialysis and dielectrophoresis

D'amico, Lorenzo; Ajami, Nadim J.; Adachi, Javier A.; Gascoyne, Peter R. C.; Petrosino, Joe

doi:10.1039/c6lc01277a

Cited by 71 publications

(60 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many label-free microfluidic methods for bacteremic blood sample preparation rely on direct size-based separation without prior lysis 26,27,45,[63][64][65][66][67][68][69] . Besides the reduction of blood cells of larger or similar diameter than the targeted bacteria and the potential release of phagocytosed but viable bacterial cells 38 , other benefits might arise from selective blood cell lysis as a first step in sample preparation.…”

Section: Discussionmentioning

confidence: 99%

Gradient acoustic focusing of sub-micron particles for separation of bacteria from blood lysate

Assche

Reithuber

Qiu

et al. 2020

Sci Rep

View full text Add to dashboard Cite

Handling of submicron-sized objects is important in many biochemical and biomedical applications, but few methods today can precisely manipulate this range of particles. We present gradient acoustic focusing that enables flow-through particle separation of submicron particles and cells and we apply it for separation of bacteria from blood lysate to facilitate their detection in whole blood for improved diagnostics. To control suspended objects below the classical 2µm size limit for acoustic focusing, we introduce a co-flowing acoustic impedance gradient to generate a stabilizing acoustic volume force that supresses acoustic streaming. the method is validated theoretically and experimentally using polystyrene particles, Staphylococcus aureus, Streptococcus pneumoniae and Escherichia coli. the applicability of the method is demonstrated by the separation of bacteria from selectively chemically lysed blood. Combined with downstream operations, this new approach opens up for novel methods for sepsis diagnostics.Microfluidic flow-through channel networks can be employed to separate or analyze biological particles by their fluorescent 1 , optical 2 , electrical 3-5 , magnetic 6,7 or bio-mechanical properties 8-12 . A major benefit with these technologies is the ability to integrate sample preparation with optical or chemical analyses on the same chip. Today, few microfluidic tools can handle suspensions containing objects below 1 µm. The main reason is that small objects have a large surface-to-volume-ratio, which makes it challenging to generate a sufficient force to drag them swiftly through a liquid.Acoustic fields can be employed inside microfluidic channels to generate strong acoustic radiation forces to spatially position suspended biological particles 13 . In acoustophoresis 14 cells are separated by their lateral displacement in response to an acoustic field while flowing through a microfluidic channel. For particles smaller than 2 µm the particle motion is normally dominated by acoustic streaming 15-17 which has been a major limitation for this technology. Several systems have been proposed that address this limitation using acoustic seed trapping 18 , acoustic vortices 19,20 or a different aspect ratio of the acoustic cavity [21][22][23][24] . Purification of small particles, e.g. bacteria and platelets [25][26][27][28] has been achieved by acoustically pushing away the larger particles from the smaller particles, but this approach does not enable isolation of sub-micron-sized biological particles from a complex background of molecules, particles or debris that are of smaller size, which is essential for purification protocols. Recently sub-micron particles were pushed away from 100-nm-particles by surface acoustic waves 29,30 and the same approach was applied to separate red blood cells and microvesicles from exosomes in a two-stage process 31 .We recently found that, for bulk acoustic waves, acoustic streaming can be greatly reduced by introducing a gradient in acoustic impedance (mass density times speed o...

show abstract

Section: Discussionmentioning

confidence: 99%

Gradient acoustic focusing of sub-micron particles for separation of bacteria from blood lysate

Assche

Reithuber

Qiu

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…A pDEP force attracts particles to the higher electric‐field gradient when their polarizability is higher than that of the medium. In general, the pDEP force is applied by pulling the target cells to electrodes and then releasing them using a suspension buffer after the DEP force is removed .…”

Section: Methodsmentioning

confidence: 99%

Automatically Controlled Microfluidic System for Continuous Separation of Rare Bacteria from Blood

et al. 2019

View full text Add to dashboard Cite

Bloodstream infection by microorganisms is a major public health concern worldwide. Millions of people per year suffer from microbial infections, and current blood culture‐based diagnostic methods are time‐consuming because of the low concentration of infectious microorganisms in the bloodstream. In this study, we introduce an efficient automated microfluidic system for the continuous isolation of rare infectious bacteria (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa) from blood. Bacteria received a balanced force between a fluidic drag force and a periodically controlled dielectrophoretic (DEP) force from tilted electrodes to minimize cell adhesion to the electrodes, which prevented the loss of rare infectious bacteria. Target bacteria were efficiently segregated from the undesired blood cells to ensure that only the bacteria received the DEP force under the hypotonic condition, while the blood cells received no DEP force and exited the channel via a laminar flow. Thus, the bacteria were successfully extracted from the blood with a high recovery yield of 91.3%, and the limit of the bacteria concentration for isolation was 100 cfu/ml. We also developed an automated system that performed every step from blood‐sample loading to application of electricity to the microfluidic chip for bacteria separation. It reduced the standard deviation of the bacteria recovery yield from 6.16 to 2.77 compared with the conventional batch process, providing stable bacteria‐extraction performance and minimizing errors and bacteria loss caused by user mistakes. © 2019 International Society for Advancement of Cytometry

show abstract

“…In this manner, a single field with a single frequency can be applied to a device, and particles experiencing a non-zero DEP force will be actuated, with those at the cross over frequency being unaffected. This approach has been used to separate cells from latex beads [21], bacteria from blood [22], and fluorescently-labeled cancer cells from blood [4]. Electrode configurations that are employed consist of interdigitated [23,24], castellated [25], ratchet [26] and trapezoidal [27] configurations.…”

Section: D Electrode Systems: Single-field/single-frequencymentioning

confidence: 99%

High-Sensitivity in Dielectrophoresis Separations

2020

View full text Add to dashboard Cite

The applications of dielectrophoretic (DEP) techniques for the manipulation of cells in a label-free fashion within microfluidic systems continue to grow. However, a limited number of methods exist for making highly sensitive separations that can isolate subtle phenotypic differences within a population of cells. This paper explores efforts to leverage that most compelling aspect of DEP—an actuation force that depends on particle electrical properties—in the background of phenotypic variations in cell size. Several promising approaches, centering around the application of multiple electric fields with spatially mapped magnitude and/or frequencies, are expanding the capability of DEP cell separation.

show abstract

Isolation and concentration of bacteria from blood using microfluidic membraneless dialysis and dielectrophoresis

Cited by 71 publications

References 33 publications

Gradient acoustic focusing of sub-micron particles for separation of bacteria from blood lysate

Gradient acoustic focusing of sub-micron particles for separation of bacteria from blood lysate

Automatically Controlled Microfluidic System for Continuous Separation of Rare Bacteria from Blood

High-Sensitivity in Dielectrophoresis Separations

Contact Info

Product

Resources

About