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Rare-cell enrichment by a rapid, label-free, ultrasonic isopycnic technique for medical diagnostics.

Bourquin Y, Syed A, Reboud J, Ranford-Cartwright LC, Barrett MP, Cooper JM - Angew. Chem. Int. Ed. Engl. (2014)

Bottom Line: 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.

View Article: PubMed Central - PubMed

Affiliation: Division of Biomedical Engineering, University of Glasgow, Glasgow, G12 8LT (UK).

No MeSH data available.


Related in: MedlinePlus

a) Photograph of the device comprising a slanted-finger interdigitated electrode (SFIDT) on LiNbO3. The surface acoustic wave (SAW) is generated at a defined position asymmetrically with respect to the drop of blood, thereby inducing a rotational motion within the drop. Scale bar: 3 mm. b) Photographs of a droplet of blood before (left) and after (right) actuation with SAW (3 s). In the actuated droplet, the red blood cells (RBCs) are concentrated in the middle, while infected RBCs (iRBCs) are enriched at the periphery. Scale bars: 1.5 mm. c) Fluorescent micrographs of the enriched iRBCs at the periphery (left) and concentrated RBCs in the center of the drop (right). Acridine orange (1.5 μg mL−1) was added to the solution to stain the parasites. Scale bars: 100 μm.
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fig01: a) Photograph of the device comprising a slanted-finger interdigitated electrode (SFIDT) on LiNbO3. The surface acoustic wave (SAW) is generated at a defined position asymmetrically with respect to the drop of blood, thereby inducing a rotational motion within the drop. Scale bar: 3 mm. b) Photographs of a droplet of blood before (left) and after (right) actuation with SAW (3 s). In the actuated droplet, the red blood cells (RBCs) are concentrated in the middle, while infected RBCs (iRBCs) are enriched at the periphery. Scale bars: 1.5 mm. c) Fluorescent micrographs of the enriched iRBCs at the periphery (left) and concentrated RBCs in the center of the drop (right). Acridine orange (1.5 μg mL−1) was added to the solution to stain the parasites. Scale bars: 100 μm.

Mentions: To achieve this, we have established an innovative technique based on an acoustically actuated microchip (Figure 1 a). The technique has been implemented in hand-held instrumentation which can be battery powered. In a first example, we study the performance of the microchip by enriching the circulating ring stage of Plasmodium falciparum in malaria-infected red blood cells (iRBCs). It is noteworthy that it is only the ring stage of this Plasmodium species that circulates in the peripheral blood, and is thus available within a fingerprick of blood; It is therefore important that any diagnostic or enrichment technique can demonstrate the separation of this specific parasite stage. Our method is based on developing unique flow patterns generated by the interaction of surface acoustic waves (SAWs) with blood, which, when coupled with a density gradient akin to that used in isopycnic techniques, results in the separation of parasites and parasite-infected cells from non-infected cells (Figure 1 b,c and Video 1 in the Supporting Information). Only a few microliters of blood are required, without the need for tubes, pumps, or centrifuges. Current standard methods are discussed in Note 1 in the Supporting Information


Rare-cell enrichment by a rapid, label-free, ultrasonic isopycnic technique for medical diagnostics.

Bourquin Y, Syed A, Reboud J, Ranford-Cartwright LC, Barrett MP, Cooper JM - Angew. Chem. Int. Ed. Engl. (2014)

a) Photograph of the device comprising a slanted-finger interdigitated electrode (SFIDT) on LiNbO3. The surface acoustic wave (SAW) is generated at a defined position asymmetrically with respect to the drop of blood, thereby inducing a rotational motion within the drop. Scale bar: 3 mm. b) Photographs of a droplet of blood before (left) and after (right) actuation with SAW (3 s). In the actuated droplet, the red blood cells (RBCs) are concentrated in the middle, while infected RBCs (iRBCs) are enriched at the periphery. Scale bars: 1.5 mm. c) Fluorescent micrographs of the enriched iRBCs at the periphery (left) and concentrated RBCs in the center of the drop (right). Acridine orange (1.5 μg mL−1) was added to the solution to stain the parasites. Scale bars: 100 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4232275&req=5

fig01: a) Photograph of the device comprising a slanted-finger interdigitated electrode (SFIDT) on LiNbO3. The surface acoustic wave (SAW) is generated at a defined position asymmetrically with respect to the drop of blood, thereby inducing a rotational motion within the drop. Scale bar: 3 mm. b) Photographs of a droplet of blood before (left) and after (right) actuation with SAW (3 s). In the actuated droplet, the red blood cells (RBCs) are concentrated in the middle, while infected RBCs (iRBCs) are enriched at the periphery. Scale bars: 1.5 mm. c) Fluorescent micrographs of the enriched iRBCs at the periphery (left) and concentrated RBCs in the center of the drop (right). Acridine orange (1.5 μg mL−1) was added to the solution to stain the parasites. Scale bars: 100 μm.
Mentions: To achieve this, we have established an innovative technique based on an acoustically actuated microchip (Figure 1 a). The technique has been implemented in hand-held instrumentation which can be battery powered. In a first example, we study the performance of the microchip by enriching the circulating ring stage of Plasmodium falciparum in malaria-infected red blood cells (iRBCs). It is noteworthy that it is only the ring stage of this Plasmodium species that circulates in the peripheral blood, and is thus available within a fingerprick of blood; It is therefore important that any diagnostic or enrichment technique can demonstrate the separation of this specific parasite stage. Our method is based on developing unique flow patterns generated by the interaction of surface acoustic waves (SAWs) with blood, which, when coupled with a density gradient akin to that used in isopycnic techniques, results in the separation of parasites and parasite-infected cells from non-infected cells (Figure 1 b,c and Video 1 in the Supporting Information). Only a few microliters of blood are required, without the need for tubes, pumps, or centrifuges. Current standard methods are discussed in Note 1 in the Supporting Information

Bottom Line: 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.

View Article: PubMed Central - PubMed

Affiliation: Division of Biomedical Engineering, University of Glasgow, Glasgow, G12 8LT (UK).

No MeSH data available.


Related in: MedlinePlus