Analytical and Bioanalytical Chemistry

, Volume 409, Issue 1, pp 275–285 | Cite as

Design and microfabrication of a miniature fiber optic probe with integrated lenses and mirrors for Raman and fluorescence measurements

  • Thitaphat Ngernsutivorakul
  • Cynthia M. Cipolla
  • Colleen E. Dugan
  • Shi Jin
  • Michael D. Morris
  • Robert T. Kennedy
  • Francis W. L. Esmonde-White
Research Paper


Fiber optics coupled to components such as lenses and mirrors have seen extensive use as probes for Raman and fluorescence measurements. Probes can be placed directly on or into a sample to allow for simplified and remote application of these optical techniques. The size and complexity of such probes however limits their application. We have used microfabrication in polydimethylsiloxane (PDMS) to create compact probes that are 0.5 mm thick by 1 mm wide. The miniature probes incorporate pre-aligned mirrors, lenses, and two fiber optic guides to allow separate input and output optical paths suitable for Raman and fluorescence spectroscopy measurements. The fabricated probe has 70 % unidirectional optical throughput and generates no spectral artifacts in the wavelength range of 200 to 800 nm. The probe is demonstrated for measurement of fluorescence within microfluidic devices and collection of Raman spectra from a pharmaceutical tablet. The fluorescence limit of detection was 6 nM when using the probe to measure resorufin inside a 150-μm inner diameter glass capillary, 100 nM for resorufin in a 60-μm-deep × 100-μm-wide PDMS channel, and 11 nM for fluorescein in a 25-μm-deep × 80-μm-wide glass channel. It is demonstrated that the same probe can be used on different sample types, e.g., microfluidic chips and tablets. Compared to existing Raman and fluorescence probes, the microfabricated probes enable measurement in smaller spaces and have lower fabrication cost.

Graphical abstract

A microfabricated spectroscopic probe with integrated optics was developed for chemical detection in small spaces and in remote applications


Microfabrication/microfluidics Miniaturized optical probe Spectroscopy Remote application Diagnostics 



We acknowledge Professor Fred Terry (EECS, UMich) for measuring the refractive index of PDMS, Brian Johnson (CHE, UMich) for the assistance with multilayer mask alignment, Jim Tedesco (Kaiser Optical Systems) for the help with Zemax modelling, and Rafal Pawluczyk (Fiber Tech Optical) for the advice and donation of various supplies in support of this project. This work was supported by NIH R37DK46960 & R37EB003320 (R.T.K.) and R01AR056646 (M.D.M.).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

216_2016_9999_MOESM1_ESM.pdf (1.3 mb)
ESM 1 (PDF 1.31 mb)


  1. 1.
    De Beer T, Burggraeve A, Fonteyne M, Saerens L, Remon JP, Vervaet C. Near infrared and Raman spectroscopy for the in-process monitoring of pharmaceutical production processes. Int J Pharm. 2011;417(1–2):32–47.CrossRefGoogle Scholar
  2. 2.
    Blanco M, Villarroya I. NIR spectroscopy: a rapid-response analytical tool. TrAC Trends Anal Chem. 2002;21(4):240–50.CrossRefGoogle Scholar
  3. 3.
    Wolfbeis OS. Fiber-optic chemical sensors and biosensors. Anal Chem. 2008;80(12):4269–83.CrossRefGoogle Scholar
  4. 4.
    Wang J, Bergholt MS, Zheng W, Huang Z. Development of a beveled fiber-optic confocal Raman probe for enhancing in vivo epithelial tissue Raman measurements at endoscopy. Opt Lett. 2013;38(13):2321.CrossRefGoogle Scholar
  5. 5.
    Schwarz RA, Arifler D, Chang SK, Pavlova I, Hussain IA, Mack V, et al. Ball lens coupled fiber-optic probe for depth-resolved spectroscopy of epithelial tissue. Opt Lett. 2005;30(10):1159–61.CrossRefGoogle Scholar
  6. 6.
    Shim MG, Song L-MWK, Marcon NE, Wilson BC. In vivo near-infrared Raman spectroscopy: demonstration of feasibility during clinical gastrointestinal endoscopy. Photochem Photobiol. 2000;72(1):146–50.Google Scholar
  7. 7.
    Bergholt MS, Zheng W, Ho KY, Teh M, Yeoh KG, So JBY, et al. Fiber-optic Raman spectroscopy probes gastric carcinogenesis in vivo at endoscopy. J Biophotonics. 2013;6(1):49–59.CrossRefGoogle Scholar
  8. 8.
    Krogmeier JR, Schaefer I, Seward G, Yantz GR, Larson JW. An integrated optics microfluidic device for detecting single DNA molecules. Lab Chip. 2007;7(12):1767.CrossRefGoogle Scholar
  9. 9.
    Kaigala GV, Bercovici M, Behnam M, Elliott D, Santiago JG, Backhouse CJ. Miniaturized system for isotachophoresis assays. Lab Chip. 2010;10(17):2242.CrossRefGoogle Scholar
  10. 10.
    Day JCC, Bennett R, Smith B, Kendall C, Hutchings J, Meaden GM, et al. A miniature confocal Raman probe for endoscopic use. Phys Med Biol. 2009;54(23):7077–87.CrossRefGoogle Scholar
  11. 11.
    Grimbergen MCM, van Swol CFP, Draga ROP, van Diest P, Verdaasdonk RM, Stone N, Bosch JHLR. Bladder cancer diagnosis during cystoscopy using Raman spectroscopy. In SPIE; 2009;716114 – 6.Google Scholar
  12. 12.
    Latka I, Dochow S, Krafft C, Dietzek B, Bartelt H, Popp J. Development of a fiber-based Raman probe for clinical diagnostics. In: Ramanujam N, Jürgen P, editors. Clinical and biomedical spectroscopy and imaging II. Munich: SPIE and Optical Society of America; 2011. 80872D-1-8.Google Scholar
  13. 13.
    Komachi Y, Katagiri T, Sato H, Tashiro H. Improvement and analysis of a micro Raman probe. Appl Opt. 2009;48(9):1683–96.CrossRefGoogle Scholar
  14. 14.
    Burns MA, Johnson BN, Brahmasandra SN, Handique K, Webster JR, Krishnan M, et al. An integrated nanoliter DNA analysis device. Science. 1998;282(5388):484–7.CrossRefGoogle Scholar
  15. 15.
    Roulet J-C, Völkel R, Herzig HP, Verpoorte E, de Rooij NF, Dändliker R. Performance of an integrated microoptical system for fluorescence detection in microfluidic systems. Anal Chem. 2002;74(14):3400–7.CrossRefGoogle Scholar
  16. 16.
    Verpoorte E. Focus. Lab Chip. 2003;3(3):42N–52.CrossRefGoogle Scholar
  17. 17.
    Roman GT, Kennedy RT. Fully integrated microfluidic separations systems for biochemical analysis. J Chromatogr A. 2007;1168(1):170–88.CrossRefGoogle Scholar
  18. 18.
    Mogensen KB, Kutter JP. Optical detection in microfluidic systems. Electrophoresis. 2009;30(S1):S92–100.CrossRefGoogle Scholar
  19. 19.
    Zeng X, Jiang H. Liquid tunable microlenses based on MEMS techniques. J Phys Appl Phys. 2013;46(32):323001.CrossRefGoogle Scholar
  20. 20.
    Vieillard J, Mazurczyk R, Morin C, Hannes B, Chevolot Y, Desbene P, et al. Application of microfluidic chip with integrated optics for electrophoretic separations of proteins. J Chromatogr B. 2007;845(2):218–25.CrossRefGoogle Scholar
  21. 21.
    Bliss CL, McMullin JN, Backhouse CJ. Rapid fabrication of a microfluidic device with integrated optical waveguides for DNA fragment analysis. Lab Chip. 2007;7(10):1280.CrossRefGoogle Scholar
  22. 22.
    Godin J, Chen C-H, Cho SH, Qiao W, Tsai F, Lo Y-H. Microfluidics and photonics for Bio-System-on-a-Chip: a review of advancements in technology towards a microfluidic flow cytometry chip. J Biophotonics. 2008;1(5):355–76.CrossRefGoogle Scholar
  23. 23.
    Becker H, Gärtner C. Polymer microfabrication technologies for microfluidic systems. Anal Bioanal Chem. 2007;390(1):89–111.CrossRefGoogle Scholar
  24. 24.
    Nge PN, Rogers CI, Woolley AT. Advances in microfluidic materials, functions, integration, and applications. Chem Rev. 2013;113(4):2550–83.CrossRefGoogle Scholar
  25. 25.
    Camou S, Fujita H, Fujii T. PDMS 2D optical lens integrated with microfluidic channels: principle and characterization. Lab Chip. 2003;3(1):40.CrossRefGoogle Scholar
  26. 26.
    Seo J, Lee LP. Disposable integrated microfluidics with self-aligned planar microlenses. Sensors Actuators B Chem. 2004;99(2–3):615–22.CrossRefGoogle Scholar
  27. 27.
    Jiang L, Pau S. Integrated waveguide with a microfluidic channel in spiral geometry for spectroscopic applications. Appl Phys Lett. 2007;90(11):111108.CrossRefGoogle Scholar
  28. 28.
    Watts BR, Zhang Z, Xu C-Q, Cao X, Lin M. Integration of optical components on-chip for scattering and fluorescence detection in an optofluidic device. Biomed Opt Express. 2012;3(11):2784–93.CrossRefGoogle Scholar
  29. 29.
    Chang-Yen DA, Eich RK, Gale BK. A monolithic PDMS waveguide system fabricated using soft-lithography techniques. J Lightwave Technol. 2005;23(6):2088–93.CrossRefGoogle Scholar
  30. 30.
    Cai Z, Qiu W, Shao G, Wang W. A new fabrication method for all-PDMS waveguides. Sens Actuators Phys. 2013;204:44–7.CrossRefGoogle Scholar
  31. 31.
    Mao X, Waldeisen JR, Juluri BK, Huang TJ. Hydrodynamically tunable optofluidic cylindrical microlens. Lab Chip. 2007;7(10):1303.CrossRefGoogle Scholar
  32. 32.
    Tang SKY, Stan CA, Whitesides GM. Dynamically reconfigurable liquid-core liquid-cladding lens in a microfluidic channel. Lab Chip. 2008;8(3):395.CrossRefGoogle Scholar
  33. 33.
    Rosenauer M, Vellekoop MJ. 3D fluidic lens shaping—a multiconvex hydrodynamically adjustable optofluidic microlens. Lab Chip. 2009;9(8):1040–2.CrossRefGoogle Scholar
  34. 34.
    Rosenauer M, Vellekoop MJ. An adjustable optofluidic micro lens enhancing single cell analysis systems. In: Dössel O, Schlegel WC, editors. World congress on medical physics and biomedical engineering, September 7–12, 2009. Munich: Springer; 2010. p. 185–8. IFMBE Proceedings.Google Scholar
  35. 35.
    Song C, Nguyen NT, Asundi AK, Low CLN. Tunable optofluidic aperture configured by a liquid-core/liquid-cladding structure. Opt Lett. 2011;36(10):1767–9.CrossRefGoogle Scholar
  36. 36.
    Chao KS, Lin MS, Yang RJ. An in-plane optofluidic microchip for focal point control. Lab Chip. 2013;13(19):3886.CrossRefGoogle Scholar
  37. 37.
    Lin BS, Yang YC, Ho CY, Yang HY, Wang HY. A PDMS-based cylindrical hybrid lens for enhanced fluorescence detection in microfluidic systems. Sensors. 2014;14(2):2967–80.CrossRefGoogle Scholar
  38. 38.
    Chabinyc ML, Chiu DT, McDonald JC, Stroock AD, Christian JF, Karger AM, et al. An integrated fluorescence detection system in poly(dimethylsiloxane) for microfluidic applications. Anal Chem. 2001;73(18):4491–8.CrossRefGoogle Scholar
  39. 39.
    Qi S, Liu X, Ford S, Barrows J, Thomas G, Kelly K, et al. Microfluidic devices fabricated in poly(methyl methacrylate) using hot-embossing with integrated sampling capillary and fiber optics for fluorescence detection. Lab Chip. 2002;2(2):88.CrossRefGoogle Scholar
  40. 40.
    Wu MH, Cai H, Xu X, Urban JP, Cui ZF, Cui Z. A SU-8/PDMS hybrid microfluidic device with integrated optical fibers for online monitoring of lactate. Biomed Microdevices. 2005;7(4):323–9.CrossRefGoogle Scholar
  41. 41.
    Mazurczyk R, Vieillard J, Bouchard A, Hannes B, Krawczyk S. A novel concept of the integrated fluorescence detection system and its application in a lab-on-a-chip microdevice. Sensors Actuators B Chem. 2006;118(1–2):11–9.CrossRefGoogle Scholar
  42. 42.
    Irawan R, Tjin SC, Fang X, Fu CY. Integration of optical fiber light guide, fluorescence detection system, and multichannel disposable microfluidic chip. Biomed Microdevices. 2007;9(3):413–9.CrossRefGoogle Scholar
  43. 43.
    Ashok PC, Singh GP, Rendall HA, Krauss TF, Dholakia K. Waveguide confined Raman spectroscopy for microfluidic interrogation. Lab Chip. 2011;11(7):1262–70.CrossRefGoogle Scholar
  44. 44.
    Sapuppo F, Schembri F, Fortuna L, Llobera A, Bucolo M. A polymeric micro-optical system for the spatial monitoring in two-phase microfluidics. Microfluid Nanofluid. 2011;12(1–4):165–74.Google Scholar
  45. 45.
    Dugan CE, Cawthorn WP, MacDougald OA, Kennedy RT. Multiplexed microfluidic enzyme assays for simultaneous detection of lipolysis products from adipocytes. Anal Bioanal Chem. 2014;406(20):4851–9.CrossRefGoogle Scholar
  46. 46.
    Roper MG, Shackman JG, Dahlgren GM, Kennedy RT. Microfluidic chip for continuous monitoring of hormone secretion from live cells using an electrophoresis-based immunoassay. Anal Chem. 2003;75(18):4711–7.CrossRefGoogle Scholar
  47. 47.
    Harrison DJ, Fluri K, Seiler K, Effenhauser CS, Manz A. Micromachining a miniaturized capillary electrophoresis-based chemical analysis system on a chip. Science. 1993;261(5123):895–7.CrossRefGoogle Scholar
  48. 48.
    Jacobson SC, Hergenroder R, Moore AWJ, Ramsey JM. Precolumn reactions with electrophoretic analysis integrated on a microchip. Anal Chem. 1994;66(23):4127–32.CrossRefGoogle Scholar
  49. 49.
    Clark AM, Sousa KM, Jennings C, MacDougald OA, Kennedy RT. Continuous-flow enzyme assay on a microfluidic chip for monitoring glycerol secretion from cultured adipocytes. Anal Chem. 2009;81(6):2350–6.CrossRefGoogle Scholar
  50. 50.
    Free glycerol colorimetric/fluorometric assay kit. In: The BioVision index of manuals online. BioVision Incorporated. 2014. Accessed 24 Jan 2015.
  51. 51.
    Jin S, Anderson GJ, Kennedy RT. Western blotting using microchip electrophoresis interfaced to a protein capture membrane. Anal Chem. 2013;85(12):6073–9.CrossRefGoogle Scholar
  52. 52.
    Miyaki K, Guo Y, Shimosaka T, Nakagama T, Nakajima H, Uchiyama K. Fabrication of an integrated PDMS microchip incorporating an LED-induced fluorescence device. Anal Bioanal Chem. 2005;382(3):810–6.CrossRefGoogle Scholar
  53. 53.
    Li HF, Lin JM, Su RG, Uchiyama K, Hobo T. A compactly integrated laser-induced fluorescence detector for microchip electrophoresis. Electrophoresis. 2004;25(12):1907–15.CrossRefGoogle Scholar
  54. 54.
    Lee KS, Lee HLT, Ram RJ. Polymer waveguide backplanes for optical sensor interfaces in microfluidics. Lab Chip. 2007;7(11):1539.CrossRefGoogle Scholar
  55. 55.
    Llobera A, Demming S, Joensson HN, Vila-Planas J, Andersson-Svahn H, Büttgenbach S. Monolithic PDMS passband filters for fluorescence detection. Lab Chip. 2010;10(15):1987.CrossRefGoogle Scholar
  56. 56.
    Hofmann O, Wang X, Cornwell A, Beecher S, Raja A, Bradley DDC, et al. Monolithically integrated dye-doped PDMS long-pass filters for disposable on-chip fluorescence detection. Lab Chip. 2006;6(8):981.CrossRefGoogle Scholar
  57. 57.
    Richard C, Renaudin A, Aimez V, Charette PG. An integrated hybrid interference and absorption filter for fluorescence detection in lab-on-a-chip devices. Lab Chip. 2009;9(10):1371.CrossRefGoogle Scholar
  58. 58.
    Lee JN, Park C, Whitesides GM. Solvent compatibility of poly(dimethylsiloxane)-based microfluidic devices. Anal Chem. 2003;75(23):6544–54.CrossRefGoogle Scholar
  59. 59.
    Martens WN, Frost RL, Kristof J, Theo Kloprogge J. Raman spectroscopy of dimethyl sulphoxide and deuterated dimethyl sulphoxide at 298 and 77 K. J Raman Spectrosc. 2002;33(2):84–91.CrossRefGoogle Scholar
  60. 60.
    Horrocks Jr WD, Cotton FA. Infrared and Raman spectra and normal co-ordinate analysis of dimethyl sulfoxide and dimethyl sulfodize-d6. Spectrochim Acta. 1961;17:134–47.CrossRefGoogle Scholar
  61. 61.
    Wang C, Vickers TJ, Mann CK. Direct assay and shelf-life monitoring of aspirin tablets using Raman spectroscopy. J Pharm Biomed Anal. 1997;16:87–94.CrossRefGoogle Scholar
  62. 62.
    Kontoyannis CG, Orkoula M. Quantitative non-destructive determination of salicylic acid acetate in aspirin tablets by Raman spectroscopy. Talanta. 1994;41(11):1981–4.CrossRefGoogle Scholar
  63. 63.
    Pagliara S, Camposeo A, Polini A, Cingolani R, Pisignano D. Electrospun light-emitting nanofibers as excitation source in microfluidic devices. Lab Chip. 2009;9(19):2851.CrossRefGoogle Scholar
  64. 64.
    Yao B, Luo G, Wang L, Gao Y, Lei G, Ren K, et al. A microfluidic device using a green organic light emitting diode as an integrated excitation source. Lab Chip. 2005;5(10):1041.CrossRefGoogle Scholar
  65. 65.
    Kamei T, Paegel BM, Scherer JR, Skelley AM, Street RA, Mathies RA. Integrated hydrogenated amorphous Si photodiode detector for microfluidic bioanalytical devices. Anal Chem. 2003;75(20):5300–5.CrossRefGoogle Scholar
  66. 66.
    Kendall C, Day J, Hutchings J, Smith B, Shepherd N, Barr H, et al. Evaluation of Raman probe for oesophageal cancer diagnostics. Analyst. 2010;135(12):3038.CrossRefGoogle Scholar
  67. 67.
    Morris MD, Finney WF, Rajachar RM, Kohn DH. Bone tissue ultrastructural response to elastic deformation probed by Raman spectroscopy. Faraday Discuss. 2004;126:159.CrossRefGoogle Scholar
  68. 68.
    Dishinger JF, Reid KR, Kennedy RT. Quantitative monitoring of insulin secretion from single islets of Langerhans in parallel on a microfluidic chip. Anal Chem. 2009;81(8):3119–27.CrossRefGoogle Scholar
  69. 69.
    Nunemaker CS, Dishinger JF, Dula SB, Wu R, Merrins MJ, Reid KR, et al. Glucose metabolism, islet architecture, and genetic homogeneity in imprinting of [Ca2+] and insulin rhythms in mouse islets. Maedler K, editor. PLoS ONE. 2009;4(12):e8428.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Thitaphat Ngernsutivorakul
    • 1
  • Cynthia M. Cipolla
    • 1
  • Colleen E. Dugan
    • 1
  • Shi Jin
    • 1
  • Michael D. Morris
    • 1
  • Robert T. Kennedy
    • 1
    • 2
  • Francis W. L. Esmonde-White
    • 1
    • 3
  1. 1.Department of ChemistryUniversity of MichiganAnn ArborUSA
  2. 2.Department of PharmacologyUniversity of MichiganAnn ArborUSA
  3. 3.Kaiser Optical Systems IncAnn ArborUSA

Personalised recommendations