Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Microfluidic blood fractionation and lysis towards analysis of cytokine levels in red blood cells
KTH, School of Electrical Engineering and Computer Science (EECS).
2019 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

In the process of blood analysis, for biomarker detection, blood plasma or serumis analyzed, while Red blood cells (RBCs) are usually considered waste. A recentstudy has found that cytokine concentrations in RBC lysate are on average 12-fold higher than in plasma. Microfluidic devices for the extraction of plasma fromwhole blood and containers of dried blood spots have already been developed.They o↵er a small tool size, low required sample volume, and low productioncost, which makes them suitable for point-of-care applications.In this thesis, an approach of isolating and lysing RBCs in a commercial bloodfilter using a microfluidic device was investigated. The design is based on a previouslydeveloped microfluidic device for plasma extraction. It was used for plasmaextraction, washing, and RBC lysing with RBC lysis bu↵er. The device’s functionalitywas examined, and the output lysate analyzed through measurements ofhemoglobin concentration, optical microscopy and an Elisa test of the cytokineIL-3.The results show that 48% of the devices were subject to one of two problems.One was slow filling of the capillary channel, and the other was the lysate beingvisibly clear. These problems were attributed to blood cells obstructing the filtersand increasing flow resistance. The device lysate viewed through an optical microscopewas shown to contain a significant amount of blood cells in some cases,suggesting that cells were passing through the filters. The mean lysis efficiency ofthe devices was determined to be 20%, which with the Elisa test results, suggeststhat there is low rates of mixing between the RBCs and the lysate within the filtermatrix. In conclusion, the tested method of isolating and lysing RBCs needs tobe improved in terms of reliability and efficiency. It was shown to work in someof the cases, and so shows promise for future development.

Abstract [sv]

Röda blodkroppar (RB) ses vanligtvis som avfall vid blodmatningar av biomarköreri plasma eller serum. Men en ny studie har funnit att koncentrationerna av cytokiner i lyserade RB är i snitt 12 gånger högre än i plasma. Mikrofluidiska apparater som extraherar plasma från helblod har redan utvecklats. Deras fördelarär att de är små, använder små provvolymer och är billiga att producera. Detta gör dem lampliga for patientnara analyser, eller s.k. point-of-care-användning.I det här arbetet prövas en metod för att isolera och lysera RB i ett kommersiellt blodfilter, med hjälp av en mikrofluidisk apparat. Designen av apparaten är baserad på en mikrofluidisk apparat som utvecklats för plasmaextrahering. Den används för plasmaextraktion, tvätt och lysering med lyseringsbu↵ert. Appa-ratens funktionalitet undersöktes, och RB-lysatet analyserades med mätningar avhemoglobinvärden, ljusmikroskopi och en Elisa-mätning av cytokinet IL-3.Resultaten visar att 48 % av apparaterna hade något av två problem. Det ena problemet var att den kapillära kanalen fylldes långsamt, och det andra var att lysatet var till synes ofärgat. Dessa problem tillskrivs att blodceller blockerar filtren och ökar flödesmotståndet. I ljusmikroskop visade sig lysatet från apparaten i vissa fall innehålla stora mängder blodceller. Detta tyder på att celler passerat igenom filtret. Medelvärdet av lyseringse↵ektiviteten i apparaterna visades vara 20 %. Tillsammans med Elisa-resultaten tyder detta på att vätskan i filtret blandas i otillräcklig utsträckning. Sammanfattningsvis behöver metoden för att isolera och lysera RB förbättras gällande tillförlitlighet och e↵ektivitet. Den visadesig fungera i vissa fall och är därför lovande för framtida utveckling.

Place, publisher, year, edition, pages
2019. , p. 42
Series
TRITA-EECS-EX ; 2019:605
Keywords [en]
Microfluidics, Capillary action, Blood, Fractionation, Cytokine, Interleukin 3
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:kth:diva-266109OAI: oai:DiVA.org:kth-266109DiVA, id: diva2:1381330
Educational program
Master of Science - Nanotechnology
Supervisors
Examiners
Available from: 2019-12-20 Created: 2019-12-20 Last updated: 2019-12-20Bibliographically approved

Open Access in DiVA

fulltext(11505 kB)6 downloads
File information
File name FULLTEXT01.pdfFile size 11505 kBChecksum SHA-512
d55b0a682314aebb483e474881e61e2da530254b0f62355ca33bcdd449d60832c3f3841f637e837968a1928868aa5704cc016af9602f2e8eeead7d6d13568874
Type fulltextMimetype application/pdf

By organisation
School of Electrical Engineering and Computer Science (EECS)
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 6 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 37 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf