Abstract

Capillaries present a promising structure for microfluidic refractive index sensors. We demonstrate a capillary-type fluorescent core microcavity sensor based on whispering gallery mode (WGM) resonances. The device consists of a microcapillary having a layer of fluorescent silicon quantum dots (QDs) coated on the channel surface. The high effective index of the QD layer confines the electric field near the capillary channel and causes the development of WGM resonances in the fluorescence spectrum. Solutions consisting of sucrose dissolved in water were pumped through the capillary while the fluorescence WGMs were measured with a spectrometer. The device showed a refractometric sensitivity of 9.8 nm/RIU (up to 13.8 nm/RIU for higher solution refractive index) and a maximum detection limit of ~7.2 x 10−3 RIU. Modeling the field inside the capillary structure, which is analogous to a layered hollow ring resonator, shows that sensitivities as high as 100 nm/RIU and detection limits as low as ~10−5 RIU may be achievable by optimizing the QD film thickness.

© 2011 OSA

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2010 (2)

H. Li and X. Fan, “Characterization of sensing capability of optofluidic ring resonator biosensors,” Appl. Phys. Lett. 97(1), 011105 (2010).
[CrossRef]

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

2009 (4)

V. Zamora, A. Díez, M. V. Andrés, and B. Gimeno, “Interrogation of whispering-gallery modes resonances in cylindrical microcavities by backreflection detection,” Opt. Lett. 34(7), 1039–1041 (2009).
[CrossRef] [PubMed]

R. G. DeCorby, N. Ponnampalam, E. Epp, T. Allen, and J. N. McMullin, “Chip-scale spectrometry based on tapered hollow Bragg waveguides,” Opt. Express 17(19), 16632–16645 (2009).
[CrossRef] [PubMed]

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

K. B. Mogensen and J. P. Kutter, “Optical detection in microfluidic systems,” Electrophoresis 30(S1Suppl 1), S92–S100 (2009).
[CrossRef] [PubMed]

2008 (8)

P. S. Nunes, N. A. Mortensen, J. P. Kutter, and K. B. Mogensen, “Photonic crystal resonator integrated in a microfluidic system,” Opt. Lett. 33(14), 1623–1625 (2008).
[CrossRef] [PubMed]

F. Vollmer and S. Arnold, “Whispering-gallery-mode biosensing: label-free detection down to single molecules,” Nat. Methods 5(7), 591–596 (2008).
[CrossRef] [PubMed]

A. Francois and M. Himmelhaus, “Optical biosensor based on whispering gallery mode excitations in clusters of microparticles,” Appl. Phys. Lett. 92(14), 141107 (2008).
[CrossRef]

S. Pang, R. E. Beckham, and K. E. Meissner, “Quantum dot-embedded microspheres for remote refractive index sensing,” Appl. Phys. Lett. 92(22), 221108 (2008).
[CrossRef] [PubMed]

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

I. M. White and X. Fan, “On the performance quantification of resonant refractive index sensors,” Opt. Express 16(2), 1020–1028 (2008).
[CrossRef] [PubMed]

G. Yang, I. M. White, and X. Fan, “An opto-fluidic ring resonator biosensor for the detection of organophosphorus pesticides,” Sens. Actuators B Chem. 133(1), 105–112 (2008).
[CrossRef]

R. D. Kekatpure and M. L. Brongersma, “Fundamental photophysics and optical loss processes in Si-nanocrystal-doped microdisk resonators,” Phys. Rev. A 78(2), 023829 (2008).
[CrossRef]

2007 (14)

C. M. Hessel, E. J. Henderson, and J. G. C. Veinot, “An investigation of the formation and growth of oxide-embedded silicon nanocrystals in hydrogen silsesquioxane-derived nanocomposites,” J. Phys. Chem. C 111(19), 6956–6961 (2007).
[CrossRef]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

S. Haeberle and R. Zengerle, “Microfluidic platforms for lab-on-a-chip applications,” Lab Chip 7(9), 1094–1110 (2007).
[CrossRef] [PubMed]

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

E. Nuhiji and P. Mulvaney, “Detection of unlabeled oligonucleotide targets using whispering gallery modes in single, fluorescent microspheres,” Small 3(8), 1408–1414 (2007).
[CrossRef] [PubMed]

V. Zamora, A. Díez, M. V. Andrés, and B. Gimeno, “Refractometric sensor based on whispering-gallery modes of thin capillarie,” Opt. Express 15(19), 12011–12016 (2007).
[CrossRef] [PubMed]

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

N. A. Abu-Hatab, J. F. John, J. M. Oran, and M. J. Sepaniak, “Multiplexed microfluidic surface-enhanced Raman spectroscopy,” Appl. Spectrosc. 61(10), 1116–1122 (2007).
[CrossRef] [PubMed]

2006 (1)

2005 (1)

D. E. Gómez, I. Pastoriza-Santos, and P. Mulvaney, “Tunable whispering gallery mode emission from quantum-dot-doped microspheres,” Small 1(2), 238–241 (2005).
[CrossRef] [PubMed]

2004 (1)

2003 (2)

E. Krioukov, J. Greve, and C. Otto, “Performance of integrated optical microcavities for refractive index and fluorescence sensing,” Sens. Actuators B Chem. 90(1-3), 58–67 (2003).
[CrossRef]

J. Homola, “Present and future of surface plasmon resonance biosensors,” Anal. Bioanal. Chem. 377(3), 528–539 (2003).
[CrossRef] [PubMed]

1998 (1)

1994 (1)

M. L. Gorodetsky and V. S. Ilchenko, “High-Q optical whispering gallery microresonators: precession approach for spherical mode analysis and emission patterns,” Opt. Commun. 113(1-3), 133–143 (1994).
[CrossRef]

1965 (1)

Abu-Hatab, N. A.

Aderem, A.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Allen, T.

Andrés, M. V.

Arnold, S.

F. Vollmer and S. Arnold, “Whispering-gallery-mode biosensing: label-free detection down to single molecules,” Nat. Methods 5(7), 591–596 (2008).
[CrossRef] [PubMed]

Beckham, R. E.

S. Pang, R. E. Beckham, and K. E. Meissner, “Quantum dot-embedded microspheres for remote refractive index sensing,” Appl. Phys. Lett. 92(22), 221108 (2008).
[CrossRef] [PubMed]

Beumer, T. A. M.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Bolaños Quiñones, V. A.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Brongersma, M. L.

R. D. Kekatpure and M. L. Brongersma, “Fundamental photophysics and optical loss processes in Si-nanocrystal-doped microdisk resonators,” Phys. Rev. A 78(2), 023829 (2008).
[CrossRef]

Carmon, T.

Chang, R. K.

Dahint, R.

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

Deamer, D. W.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

DeCorby, R. G.

Diercks, A. H.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Díez, A.

Ding, F.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Epp, E.

Fan, X.

H. Li and X. Fan, “Characterization of sensing capability of optofluidic ring resonator biosensors,” Appl. Phys. Lett. 97(1), 011105 (2010).
[CrossRef]

I. M. White and X. Fan, “On the performance quantification of resonant refractive index sensors,” Opt. Express 16(2), 1020–1028 (2008).
[CrossRef] [PubMed]

G. Yang, I. M. White, and X. Fan, “An opto-fluidic ring resonator biosensor for the detection of organophosphorus pesticides,” Sens. Actuators B Chem. 133(1), 105–112 (2008).
[CrossRef]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

I. M. White, H. Oveys, and X. Fan, “Liquid-core optical ring-resonator sensors,” Opt. Lett. 31(9), 1319–1321 (2006).
[CrossRef] [PubMed]

Francois, A.

A. Francois and M. Himmelhaus, “Optical biosensor based on whispering gallery mode excitations in clusters of microparticles,” Appl. Phys. Lett. 92(14), 141107 (2008).
[CrossRef]

Gimeno, B.

Gómez, D. E.

D. E. Gómez, I. Pastoriza-Santos, and P. Mulvaney, “Tunable whispering gallery mode emission from quantum-dot-doped microspheres,” Small 1(2), 238–241 (2005).
[CrossRef] [PubMed]

Gorodetsky, M. L.

M. L. Gorodetsky and V. S. Ilchenko, “High-Q optical whispering gallery microresonators: precession approach for spherical mode analysis and emission patterns,” Opt. Commun. 113(1-3), 133–143 (1994).
[CrossRef]

Greve, J.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

E. Krioukov, J. Greve, and C. Otto, “Performance of integrated optical microcavities for refractive index and fluorescence sensing,” Sens. Actuators B Chem. 90(1-3), 58–67 (2003).
[CrossRef]

Haeberle, S.

S. Haeberle and R. Zengerle, “Microfluidic platforms for lab-on-a-chip applications,” Lab Chip 7(9), 1094–1110 (2007).
[CrossRef] [PubMed]

Hansen, C. L.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Hanumegowda, N. M.

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

Hawkins, A. R.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Heideman, R. G.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Henderson, E. J.

C. M. Hessel, E. J. Henderson, and J. G. C. Veinot, “An investigation of the formation and growth of oxide-embedded silicon nanocrystals in hydrogen silsesquioxane-derived nanocomposites,” J. Phys. Chem. C 111(19), 6956–6961 (2007).
[CrossRef]

Hessel, C. M.

C. M. Hessel, E. J. Henderson, and J. G. C. Veinot, “An investigation of the formation and growth of oxide-embedded silicon nanocrystals in hydrogen silsesquioxane-derived nanocomposites,” J. Phys. Chem. C 111(19), 6956–6961 (2007).
[CrossRef]

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

Himmelhaus, M.

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

A. Francois and M. Himmelhaus, “Optical biosensor based on whispering gallery mode excitations in clusters of microparticles,” Appl. Phys. Lett. 92(14), 141107 (2008).
[CrossRef]

Homola, J.

J. Homola, “Present and future of surface plasmon resonance biosensors,” Anal. Bioanal. Chem. 377(3), 528–539 (2003).
[CrossRef] [PubMed]

Huang, G.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Huskens, J.

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

Ilchenko, V. S.

M. L. Gorodetsky and V. S. Ilchenko, “High-Q optical whispering gallery microresonators: precession approach for spherical mode analysis and emission patterns,” Opt. Commun. 113(1-3), 133–143 (1994).
[CrossRef]

John, J. F.

Johnson, N. M.

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

Kanger, J. S.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Kekatpure, R. D.

R. D. Kekatpure and M. L. Brongersma, “Fundamental photophysics and optical loss processes in Si-nanocrystal-doped microdisk resonators,” Phys. Rev. A 78(2), 023829 (2008).
[CrossRef]

Kiesel, P.

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

Kiravittaya, S.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Krioukov, E.

E. Krioukov, J. Greve, and C. Otto, “Performance of integrated optical microcavities for refractive index and fluorescence sensing,” Sens. Actuators B Chem. 90(1-3), 58–67 (2003).
[CrossRef]

Kuswandi, B.

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

Kutter, J. P.

Lambeck, P. V.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Li, H.

H. Li and X. Fan, “Characterization of sensing capability of optofluidic ring resonator biosensors,” Appl. Phys. Lett. 97(1), 011105 (2010).
[CrossRef]

Liu, F. C.

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

Lock, J. A.

Lunt, E. J.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Malac, M.

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

Malitson, I.

McMullin, J. N.

Mei, Y.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Meissner, K. E.

S. Pang, R. E. Beckham, and K. E. Meissner, “Quantum dot-embedded microspheres for remote refractive index sensing,” Appl. Phys. Lett. 92(22), 221108 (2008).
[CrossRef] [PubMed]

Meldrum, A.

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

Mogensen, K. B.

Mohta, S.

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

Mortensen, N. A.

Mulvaney, P.

E. Nuhiji and P. Mulvaney, “Detection of unlabeled oligonucleotide targets using whispering gallery modes in single, fluorescent microspheres,” Small 3(8), 1408–1414 (2007).
[CrossRef] [PubMed]

D. E. Gómez, I. Pastoriza-Santos, and P. Mulvaney, “Tunable whispering gallery mode emission from quantum-dot-doped microspheres,” Small 1(2), 238–241 (2005).
[CrossRef] [PubMed]

Nuhiji, E.

E. Nuhiji and P. Mulvaney, “Detection of unlabeled oligonucleotide targets using whispering gallery modes in single, fluorescent microspheres,” Small 3(8), 1408–1414 (2007).
[CrossRef] [PubMed]

Nunes, P. S.

Nuriman, J.

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

Oran, J. M.

Otto, C.

E. Krioukov, J. Greve, and C. Otto, “Performance of integrated optical microcavities for refractive index and fluorescence sensing,” Sens. Actuators B Chem. 90(1-3), 58–67 (2003).
[CrossRef]

Oveys, H.

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

I. M. White, H. Oveys, and X. Fan, “Liquid-core optical ring-resonator sensors,” Opt. Lett. 31(9), 1319–1321 (2006).
[CrossRef] [PubMed]

Ozinsky, A.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Pang, S.

S. Pang, R. E. Beckham, and K. E. Meissner, “Quantum dot-embedded microspheres for remote refractive index sensing,” Appl. Phys. Lett. 92(22), 221108 (2008).
[CrossRef] [PubMed]

Pastoriza-Santos, I.

D. E. Gómez, I. Pastoriza-Santos, and P. Mulvaney, “Tunable whispering gallery mode emission from quantum-dot-doped microspheres,” Small 1(2), 238–241 (2005).
[CrossRef] [PubMed]

Ponnampalam, N.

Poon, A. W.

Rodriguez, D. J.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Rudenko, M. I.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Schmidt, H.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Schmidt, O.

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

Schmidt, O. G.

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Sepaniak, M. J.

Spotts, J. M.

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Subramaniam, V.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Summers, M. A.

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

Suter, J. D.

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

Vahala, K. J.

van Hövell, S. W.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Veinot, J. G. C.

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

C. M. Hessel, E. J. Henderson, and J. G. C. Veinot, “An investigation of the formation and growth of oxide-embedded silicon nanocrystals in hydrogen silsesquioxane-derived nanocomposites,” J. Phys. Chem. C 111(19), 6956–6961 (2007).
[CrossRef]

Verboom, W.

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

Vollmer, F.

F. Vollmer and S. Arnold, “Whispering-gallery-mode biosensing: label-free detection down to single molecules,” Nat. Methods 5(7), 591–596 (2008).
[CrossRef] [PubMed]

Weller, A.

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

White, I. M.

I. M. White and X. Fan, “On the performance quantification of resonant refractive index sensors,” Opt. Express 16(2), 1020–1028 (2008).
[CrossRef] [PubMed]

G. Yang, I. M. White, and X. Fan, “An opto-fluidic ring resonator biosensor for the detection of organophosphorus pesticides,” Sens. Actuators B Chem. 133(1), 105–112 (2008).
[CrossRef]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

I. M. White, H. Oveys, and X. Fan, “Liquid-core optical ring-resonator sensors,” Opt. Lett. 31(9), 1319–1321 (2006).
[CrossRef] [PubMed]

Wijn, R. R.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Wink, T.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Yang, G.

G. Yang, I. M. White, and X. Fan, “An opto-fluidic ring resonator biosensor for the detection of organophosphorus pesticides,” Sens. Actuators B Chem. 133(1), 105–112 (2008).
[CrossRef]

Yang, L.

Yin, D.

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Ymeti, A.

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Zamora, V.

Zengerle, R.

S. Haeberle and R. Zengerle, “Microfluidic platforms for lab-on-a-chip applications,” Lab Chip 7(9), 1094–1110 (2007).
[CrossRef] [PubMed]

Zhu, H.

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

J. D. Suter, I. M. White, H. Zhu, and X. Fan, “Thermal characterization of liquid core optical ring resonator sensors,” Appl. Opt. 46(3), 389–396 (2007).
[CrossRef] [PubMed]

Zourob, M.

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

ACS Nano (1)

G. Huang, V. A. Bolaños Quiñones, F. Ding, S. Kiravittaya, Y. Mei, and O. G. Schmidt, “Rolled-up optical microcavities with subwavelength wall thicknesses for enhanced liquid sensing applications,” ACS Nano 4(6), 3123–3130 (2010).
[CrossRef] [PubMed]

Adv. Mater. (Deerfield Beach Fla.) (1)

C. M. Hessel, M. A. Summers, A. Meldrum, M. Malac, and J. G. C. Veinot, “Direct patterning, conformal coating, and erbium doping of luminescent nc-Si/SiO2 thin films from solution processable hydrogen silsesquioxane,” Adv. Mater. (Deerfield Beach Fla.) 19(21), 3513–3516 (2007).
[CrossRef]

Anal. Bioanal. Chem. (1)

J. Homola, “Present and future of surface plasmon resonance biosensors,” Anal. Bioanal. Chem. 377(3), 528–539 (2003).
[CrossRef] [PubMed]

Anal. Biochem. (1)

A. H. Diercks, A. Ozinsky, C. L. Hansen, J. M. Spotts, D. J. Rodriguez, and A. Aderem, “A microfluidic device for multiplexed protein detection in nano-liter volumes,” Anal. Biochem. 386(1), 30–35 (2009).
[CrossRef] [PubMed]

Anal. Chem. (1)

H. Zhu, I. M. White, J. D. Suter, M. Zourob, and X. Fan, “Integrated refractive index optical ring resonator detector for capillary electrophoresis,” Anal. Chem. 79(3), 930–937 (2007).
[CrossRef] [PubMed]

Anal. Chim. Acta (1)

B. Kuswandi, J. Nuriman, J. Huskens, and W. Verboom, “Optical sensing systems for microfluidic devices: a review,” Anal. Chim. Acta 601(2), 141–155 (2007).
[CrossRef] [PubMed]

Appl. Opt. (2)

Appl. Phys. B (2)

O. Schmidt, P. Kiesel, S. Mohta, and N. M. Johnson, “Resolving pm wavelength shifts in optical sensing,” Appl. Phys. B 86(4), 593–600 (2007).
[CrossRef]

A. Weller, F. C. Liu, R. Dahint, and M. Himmelhaus, “Whispering gallery mode biosensors in the low-Q limit,” Appl. Phys. B 90(3-4), 561–567 (2008).
[CrossRef]

Appl. Phys. Lett. (3)

H. Li and X. Fan, “Characterization of sensing capability of optofluidic ring resonator biosensors,” Appl. Phys. Lett. 97(1), 011105 (2010).
[CrossRef]

A. Francois and M. Himmelhaus, “Optical biosensor based on whispering gallery mode excitations in clusters of microparticles,” Appl. Phys. Lett. 92(14), 141107 (2008).
[CrossRef]

S. Pang, R. E. Beckham, and K. E. Meissner, “Quantum dot-embedded microspheres for remote refractive index sensing,” Appl. Phys. Lett. 92(22), 221108 (2008).
[CrossRef] [PubMed]

Appl. Spectrosc. (1)

Electrophoresis (1)

K. B. Mogensen and J. P. Kutter, “Optical detection in microfluidic systems,” Electrophoresis 30(S1Suppl 1), S92–S100 (2009).
[CrossRef] [PubMed]

IEEE Sens. J. (1)

I. M. White, H. Zhu, J. D. Suter, N. M. Hanumegowda, H. Oveys, M. Zourob, and X. Fan, “Refractometric sensors for lab-on-a-chip based on optical ring resonators,” IEEE Sens. J. 7(1), 28–35 (2007).
[CrossRef]

J. Opt. Soc. Am. (1)

J. Phys. Chem. C (1)

C. M. Hessel, E. J. Henderson, and J. G. C. Veinot, “An investigation of the formation and growth of oxide-embedded silicon nanocrystals in hydrogen silsesquioxane-derived nanocomposites,” J. Phys. Chem. C 111(19), 6956–6961 (2007).
[CrossRef]

Lab Chip (2)

S. Haeberle and R. Zengerle, “Microfluidic platforms for lab-on-a-chip applications,” Lab Chip 7(9), 1094–1110 (2007).
[CrossRef] [PubMed]

D. Yin, E. J. Lunt, M. I. Rudenko, D. W. Deamer, A. R. Hawkins, and H. Schmidt, “Planar optofluidic chip for single particle detection, manipulation, and analysis,” Lab Chip 7(9), 1171–1175 (2007).
[CrossRef] [PubMed]

Nano Lett. (1)

A. Ymeti, J. Greve, P. V. Lambeck, T. Wink, S. W. van Hövell, T. A. M. Beumer, R. R. Wijn, R. G. Heideman, V. Subramaniam, and J. S. Kanger, “Fast, ultrasensitive virus detection using a Young interferometer sensor,” Nano Lett. 7(2), 394–397 (2007).
[CrossRef] [PubMed]

Nat. Methods (1)

F. Vollmer and S. Arnold, “Whispering-gallery-mode biosensing: label-free detection down to single molecules,” Nat. Methods 5(7), 591–596 (2008).
[CrossRef] [PubMed]

Opt. Commun. (1)

M. L. Gorodetsky and V. S. Ilchenko, “High-Q optical whispering gallery microresonators: precession approach for spherical mode analysis and emission patterns,” Opt. Commun. 113(1-3), 133–143 (1994).
[CrossRef]

Opt. Express (4)

Opt. Lett. (4)

Phys. Rev. A (1)

R. D. Kekatpure and M. L. Brongersma, “Fundamental photophysics and optical loss processes in Si-nanocrystal-doped microdisk resonators,” Phys. Rev. A 78(2), 023829 (2008).
[CrossRef]

Sens. Actuators B Chem. (2)

G. Yang, I. M. White, and X. Fan, “An opto-fluidic ring resonator biosensor for the detection of organophosphorus pesticides,” Sens. Actuators B Chem. 133(1), 105–112 (2008).
[CrossRef]

E. Krioukov, J. Greve, and C. Otto, “Performance of integrated optical microcavities for refractive index and fluorescence sensing,” Sens. Actuators B Chem. 90(1-3), 58–67 (2003).
[CrossRef]

Small (2)

E. Nuhiji and P. Mulvaney, “Detection of unlabeled oligonucleotide targets using whispering gallery modes in single, fluorescent microspheres,” Small 3(8), 1408–1414 (2007).
[CrossRef] [PubMed]

D. E. Gómez, I. Pastoriza-Santos, and P. Mulvaney, “Tunable whispering gallery mode emission from quantum-dot-doped microspheres,” Small 1(2), 238–241 (2005).
[CrossRef] [PubMed]

Other (5)

I. M. White, H. Zhu, J. D. Suter, X. Fan, and M. Zourob, Methods in Molecular Biology: Biosensors and Biodetection, edited by A. Rasooly and K.E. Herold, (Humana Press, 2009). Chap. 7.

H. Dirac and P. Gravesen, “Realisation and characterisation of all liquid optical waveguides,” Proc. MEMS. 14th IEEE International Conference on Micro Electro Mechanical systems, 4590462 (2001).

Some examples include FluimedX ( www.fluimedx.com ), Biacore ( www.biacore.com ), and Farfield Sensors ( www.farfield-group.com ).

Product numbers TSP025375 and TSP100170, respectively, from Polymicro Technologies ( www.polymicro.com ).

Known by its standard trade name FoX-15, Dow Corning, Inc. FoX-15 is a negative electron beam resist.

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Figures (9)

Fig. 1
Fig. 1

Schematic of the fluorescent capillary structure. The WGMs are confined in the QD film coated on the inner capillary surface. The fields associated with the TEz polarization are shown with colored arrows. The polarization is defined with respect to the plane of propagation of the WGMs.

Fig. 2
Fig. 2

(a) Scanning electron micrograph showing part of a quantum dot film extruding from the cleaved end of an FCM channel. (b) TEM micrograph from a flat film, showing several QDs embedded in a glassy matrix (highlighted by the white ellipses). Electron diffraction (not shown) confirmed the presence of randomly-oriented Si-QDs.

Fig. 3
Fig. 3

Transmission and fluorescence images for a) 25 um ID (Type-I) and b) 100 um ID (Type-II) glass capillaries coated with a Si-QD film.

Fig. 4
Fig. 4

PL spectra for a) 100 μm ID and b) 25 μm ID capillaries indicating TMz and TEz WGMs, separated using a linear polarizer. The TEz polarized modes (electric field parallel to the capillary axis) are more intense than for the TMz case, and were therefore used for the refractometric measurements. Data offset for clarity.

Fig. 5
Fig. 5

Shifts in WGM fluorescence for different sucrose solutions in the channel of (a) a 25-μm-ID Type-I capillary; (b) same as in (a) but with a 405-nm LED pump; and (c) a 100 μm-ID Type-II capillary. Insets show the WGM wavelength shifts.

Fig. 6
Fig. 6

Mode profile of a WGM (ρ = 1, l = 160, λ0 = 804.58 nm) propagating in a 25-μm-diameter capillary with a 500-nm-thick film (indicated in red), calculated from FDFD computations. The field is mostly confined in the QD film. Inset Refractive index profile of simulated structure: n1 = 1.40, n2 = 1.67 (QD film), and n3 = 1.45 (silica).

Fig. 7
Fig. 7

FDFD-calculated WGM resonance shifts for Type-I (solid) and Type-II (dashed) FCMs, as a function of QD layer thickness. Inset Refractometric sensitivity of Type-I (solid) and Type-II (dashed) capillaries at n1 = 1.375 (solid vertical line in main figure). Film thickness influences the refractometric sensitivity of the device, sharply increasing for “thin” films. For a given film thickness, the larger diameter capillary shows higher refractometric sensitivity.

Fig. 8
Fig. 8

A single mode from a Type-I capillary, with a double-Lorentzian fit. Data was fit in frequency space then translated to wavelength for visualization. The inset shows the experimental and calculated resonance shifts. The solid line corresponds to the shift obtained from FDFD computations for the l = 160 mode in a Type-I capillary with a 525-nm-thick film. The resonance shift of this peak is approximately quadratic with respect to the refractive index of the analyte, n1, as shown by the dashed curve, which included the n1 = 1 data point in the fit. The maximum refractometric sensitivity, given by the slope of this curve at n1 = 1.45, is 13.8 nm/RIU (whereas, the linear sensitivity over the more limited range shown was 9.8 nm/RIU).

Fig. 9
Fig. 9

Shift in peak resonance wavelength of a WGM in (a) a Type-II capillary; and, (b) a Type-II capillary, as a function of incident laser power. The slope of the least-squares linear fit gave a thermal shift of 0.4 pm/mW of laser power for Type-I FCMs and 1.4 pm/mW for Type-II. Some of the jitter in the data is due to random errors in the measurement or the peak fitting routine, as discussed previously. All shifts were measured with respect to the first data point (which has a zero shift, by definition).

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