Monolithic PDMS passband filters for fluorescence detection
2010 (English)In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 10, no 15, 1987-1992 p.Article in journal (Refereed) Published
We present the fabrication and characteristics of monolithically integrated ink dyed poly(dimethylsiloxane) (PDMS) filters for optical sensing in disposable lab-on-a-chip. This represents a migration of auxillary functions onto the disposable chip with the goal of producing truly portable systems. Filters made from commercially available ink (Pelikan) directly mixed into PDMS oligomer without the use of any additional solvents were patterned with standard soft lithography technologies. Furthermore, a fabrication process based on capillary forces is presented allowing PDMS coloration of arbitrary shapes. Different filters of varying thickness fabricated using red, green and blue ink in four different concentrations were characterized. The optimal performance was found with filter thicknesses of 250 mm and ink to PDMS ratios of 0.1 (mL ink : mL PDMS oligomer) resulting in a transmittance ranging from -15.1 dB to -12.3 dB in the stopband and from -4.0 dB to -2.5 dB in the passband. Additionally, we demonstrate the robustness of this approach as the ink dyed PDMS filters do not exhibit temporal ageing due to diffusion or autofluorescence. We also show that such filters can easily be integrated in fluorescence systems, with stopbands efficient enough to allow fluorescence measurements under non-optimal conditions (broadband excitation, 180 degrees configuration). Integrated ink dyed PDMS filters add robust optical functionalities to disposable microdevices at a low cost and will enable the use of these devices for a wide range of fluorescence and absorbance based biological and chemical analysis.
Place, publisher, year, edition, pages
2010. Vol. 10, no 15, 1987-1992 p.
HOLLOW PRISMS, POLY(DIMETHYLSILOXANE), ABSORPTION, SENSORS, ARRAYS, SYSTEM, CHIP
IdentifiersURN: urn:nbn:se:kth:diva-29482DOI: 10.1039/c003575kISI: 000279851200015ScopusID: 2-s2.0-77954619141OAI: oai:DiVA.org:kth-29482DiVA: diva2:395138
FunderEU, FP7, Seventh Framework Programme, (FP7/2007-2013)/ERC 209243
QC 201102042011-02-042011-02-022011-02-25Bibliographically approved