%0 Journal Article %1 Waechter2009 %A Waechter, Helen %A Bescherer, Klaus %A Dürr, Christoph J. %A Oleschuk, Richard D. %A Loock, Hans-Peter %D 2009 %J Analytical Chemistry %K %N 21 %P 9048–9054 %R 10.1021/ac901696q %T 405 nm Absorption Detection in Nanoliter Volumes %V 81 %X Analytical UV absorption detection for microfluidic devices, capillary electrophoresis, and even high-performance liquid chromatography is hampered by the small detection volumes, short absorption paths, and the need to sample at a high rate with a stable background and low noise. Fiber-loop ring-down spectroscopy (FLRDS) permits absorption detection of dilute liquid samples in volumes as small as a few nanoliters, while being insensitive to light source fluctuations and permitting a millisecond temporal resolution. We demonstrate a FLRDS based detection scheme that is compatible in dimensions (<200 μm absorption path, 6.0 nL detection volume) and optical design (405 nm detection wavelength, fiber coupled) with existing separation systems. An optical/fluidic interface has been built that allows injection of laser light into the loop while also permitting delivery of the sample. The detection limit of tartrazine was determined to be 5 μM (30 fmol) corresponding to an absorption of 0.11 cm−1. Equivalent results were obtained when detecting myoglobin, a heterocyclic pharmaceutical ingredient, and 5.17 μm diameter polystyrene beads.

@article{Waechter2009, abstract = {Analytical UV absorption detection for microfluidic devices, capillary electrophoresis, and even high-performance liquid chromatography is hampered by the small detection volumes, short absorption paths, and the need to sample at a high rate with a stable background and low noise. Fiber-loop ring-down spectroscopy (FLRDS) permits absorption detection of dilute liquid samples in volumes as small as a few nanoliters, while being insensitive to light source fluctuations and permitting a millisecond temporal resolution. We demonstrate a FLRDS based detection scheme that is compatible in dimensions (<200 μm absorption path, 6.0 nL detection volume) and optical design (405 nm detection wavelength, fiber coupled) with existing separation systems. An optical/fluidic interface has been built that allows injection of laser light into the loop while also permitting delivery of the sample. The detection limit of tartrazine was determined to be 5 μM (30 fmol) corresponding to an absorption of 0.11 cm−1. Equivalent results were obtained when detecting myoglobin, a heterocyclic pharmaceutical ingredient, and 5.17 μm diameter polystyrene beads.}, added-at = {2011-10-01T00:01:29.000+0200}, author = {Waechter, Helen and Bescherer, Klaus and Dürr, Christoph J. and Oleschuk, Richard D. and Loock, Hans-Peter}, biburl = {https://www.bibsonomy.org/bibtex/2f2ba2c1fbc3d19ffeb35b8a379141023/afcallender}, doi = {10.1021/ac901696q}, file = {Waechter2009.pdf:indexed\\Waechter2009.pdf:PDF}, groups = {public}, interhash = {319a96d10d85132aabc521e73958cb9b}, intrahash = {f2ba2c1fbc3d19ffeb35b8a379141023}, journal = {Analytical Chemistry}, keywords = {}, number = 21, pages = {9048–9054}, timestamp = {2011-10-01T00:01:29.000+0200}, title = {405 nm Absorption Detection in Nanoliter Volumes}, username = {afcallender}, volume = 81, year = 2009 }