Patterned self-assembled beads in silicon channels
2001 (English)In: Electrophoresis, ISSN 0173-0835, E-ISSN 1522-2683, Vol. 22, no 18, 3876-3882 p.Article in journal (Refereed) Published
A novel technique enabling selective bead trapping in microfluidic devices without the use of physical barriers is presented in this paper. It is a fast, convenient and simple method, involving microcontact printing and self-assembly, that can be applied to silicon, quartz or plastic substrates. In the first step, channels are etched in the substrate. The surface chemistry of the internal walls of the channels is then modified by microcontact printing. The chip is submerged in a bead slurry where beads self-assemble based on surface chemistry and immobilize on the internal walls of the channels. Silicon channels (100 mum wide and 50 mum deep) have been covered with monolayers of streptavidin-, amino- and hydroxy-functionalized microspheres and resulted in good surface coverage of beads on the channel walls. A high-resolution pattern of lines of self-assembled streptavidin beads, as narrow as 5 mum, has also been generated on the bottom of a 500 mum wide and 50 mum deep channel. Flow tests were performed in sealed channels with the different immobilized beads to confirm that the immobilized beads could withstand the forces generated by water flowing in the channels. The presented results indicate that single beads can be precisely positioned within microfluidic devices based on self-assembly which is useful as screening and analysis tools within the field of biochemistry and organic chemistry.
Place, publisher, year, edition, pages
2001. Vol. 22, no 18, 3876-3882 p.
microcontact printing, self-assembly, beads, microfluidics, through filter-chamber, microfluidic systems, integration
IdentifiersURN: urn:nbn:se:kth:diva-21064ISI: 000171863900005OAI: oai:DiVA.org:kth-21064DiVA: diva2:339761
QC 201005252010-08-102010-08-10Bibliographically approved