TY - JOUR
T1 - Microfabrication and characterization of Teflon AF-coated liquid core waveguide channels in silicon
AU - Datta, Arindom
AU - Eom, In Yong
AU - Dhar, Achintya
AU - Kuban, Petr
AU - Manor, Rosalynn
AU - Ahmad, Iftikhar
AU - Gangopadhyay, Shubhra
AU - Dallas, Tim
AU - Holtz, Mark
AU - Temkin, Henryk
AU - Dasgupta, Purnendu K.
N1 - Funding Information:
Manuscript received October 28, 2002; revised April 14, 2003. This work was supported in part by the National Science Foundation under Grants CTS-088198, ECS-0070240. The associate editor coordinating the review of this paper and approving it for publication was Dr. Michiel Vellekoop.
PY - 2003/12
Y1 - 2003/12
N2 - The fabrication and testing of Teflon AF-coated channels on silicon and bonding of the same to a similarly coated glass wafer are described. With water or aqueous solutions in such channels, the channels exhibit much better light conduction ability than similar uncoated channels. Although the loss is greater than extruded Teflon AF tubes, light throughput is far superior to channels described in the literature consisting of [110] planes in silicon with 45° sidewalls. Absorbance noise levels under actual flow conditions using an LED source, an inexpensive photodiode and a simple operational amplifier circuitry was 1 × 10-4 absorbance units over a 10-mm path length (channel 0.17-mm deep × 0.49-mm wide), comparable to many commercially available macroscale flow-through absorbance detectors. Adherence to Beer's law was tested over a 50-fold concentration range of an injected dye, with the linear r 2 relating the concentration to the observed absorbance being 0.9993. Fluorescence detection was tested with fluorescein as the test solute, a high brightness blue LED as the excitation source and an inexpensive miniature PMT. The concentration detection limit was 3 × 10-9 M and the corresponding mass detection limit was estimated to be 5 × 10 -16 mol.
AB - The fabrication and testing of Teflon AF-coated channels on silicon and bonding of the same to a similarly coated glass wafer are described. With water or aqueous solutions in such channels, the channels exhibit much better light conduction ability than similar uncoated channels. Although the loss is greater than extruded Teflon AF tubes, light throughput is far superior to channels described in the literature consisting of [110] planes in silicon with 45° sidewalls. Absorbance noise levels under actual flow conditions using an LED source, an inexpensive photodiode and a simple operational amplifier circuitry was 1 × 10-4 absorbance units over a 10-mm path length (channel 0.17-mm deep × 0.49-mm wide), comparable to many commercially available macroscale flow-through absorbance detectors. Adherence to Beer's law was tested over a 50-fold concentration range of an injected dye, with the linear r 2 relating the concentration to the observed absorbance being 0.9993. Fluorescence detection was tested with fluorescein as the test solute, a high brightness blue LED as the excitation source and an inexpensive miniature PMT. The concentration detection limit was 3 × 10-9 M and the corresponding mass detection limit was estimated to be 5 × 10 -16 mol.
UR - http://www.scopus.com/inward/record.url?scp=3042739618&partnerID=8YFLogxK
U2 - 10.1109/JSEN.2003.820343
DO - 10.1109/JSEN.2003.820343
M3 - Article
AN - SCOPUS:3042739618
SN - 1530-437X
VL - 3
SP - 788
EP - 795
JO - IEEE Sensors Journal
JF - IEEE Sensors Journal
IS - 6
ER -