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Microfluidics and Nanofluidics

, 23:105 | Cite as

LED-based opto-wetting and fluidic transport for droplet mixing

  • Tony Thomas
  • Harikrishnan Narayanan UnniEmail author
Research Paper
  • 113 Downloads

Abstract

Light energy is utilized as an extensive tool for actuation of fluid flow in microfluidic devices. We report a novel method of droplet actuation using LED (light-emitting diode) that can be utilized for microfluidic mixing applications. This low power LED which emits light of peak wavelength 395 nm delivering luminous power of less than 300 millicandela (mcd) was used to create an interfacial tension gradient on solid–liquid interface containing photoresponsive molecule of azobenzene (C12H10N2). LED-induced photoisomerization of azobenzene creates a spatial gradient in interfacial energy on the solid–liquid interface, which enhances the droplet movement. The concept of LED-enhanced fluidic actuation was demonstrated using droplets of water, urine, blood serum over photoresponsive substrate. The substrates were prepared by coating the surface of silicon substrate with azobenzene dissolved in silicone resin solution. Detailed experimental characterization of LED-actuated droplet velocity was performed, where the effect of parameters such as frequency of light actuation, droplet volume, concentration of azobenzene was evaluated. Droplet transport of DI water (de-ionized) of volume 60 µL was achieved at a velocity of 160 µm/s corresponding to LED actuation frequency of 1 Hz. In vitro quantification of blood calcium and urine pH was performed using fabricated chip scale opto-wetting platforms. The proposed work could be useful in the development of droplet microfluidic chips, where combinatorial mixing can be achieved using an array of LEDs.

Keywords

Photoisomerization Interfacial tension LED Azobenzene Photoresponsive Contact angle Surface energy 

Notes

Acknowledgements

The authors express there sincere thanks to Ministry of Human Resources and Development, Government of India and IIT Hyderabad for their financial support to this project.

Compliance with ethical standards

Conflict of interest

The authors disclose that there is no conflicts of interest to declare.

References

  1. Arscott S (2011) Moving liquids with light: photoelectrowetting on semiconductors. Nat Sci Rep 1:184.  https://doi.org/10.1038/srep00184 CrossRefGoogle Scholar
  2. Baigl D (2012) Photoactuation of liquids for light driven microfluidics. Lab Chip 12:3637–3653.  https://doi.org/10.1039/c2lc40596b CrossRefGoogle Scholar
  3. Baron DN, Bell JL (1957) A simple specific titration method for serum calcium. Clin Chim Acta 2(4):327–331.  https://doi.org/10.1016/0009-8981(57)90010-4 CrossRefGoogle Scholar
  4. Baroud CN, Robert M, Delville JP (2007) An optical toolbox for total control of droplet microfluidics. Lab Chip 7:1029–1033.  https://doi.org/10.1039/b702472j CrossRefGoogle Scholar
  5. Bonn D, Eggers J, Indekeu J (2009) Wetting and spreading. Rev Mod Phys 81(2):739.  https://doi.org/10.1103/RevModPhys.81.739 CrossRefGoogle Scholar
  6. Brochard F (1989) Motion of droplets on solid surface induced by chemical or thermal gradients. Langmuir 5:2.  https://doi.org/10.1021/la00086a025 CrossRefGoogle Scholar
  7. Chiou PY, Park SY, Wu MC (2008a) Continuous optoelectrowetting for picoliter droplet manipulation. Appl Phys Lett 93:221110.  https://doi.org/10.1063/1.3039070 CrossRefGoogle Scholar
  8. Chiou PY, Chang Z, Wu MC (2008b) Droplet manipulation with light on optoelectrowetting device. J Microelectromech Syst 17(1):133–138.  https://doi.org/10.1109/jmems.2007.904336 CrossRefGoogle Scholar
  9. Connerty HV, Briggs AR (1966) Determination of serum calcium by means of orthocresolphthalein complexone. Am J Clin Pathol 45(3):290–296.  https://doi.org/10.1093/ajcp/45.3.290 CrossRefGoogle Scholar
  10. Cook JD, Caplan YH, Bush DM (2000) The characterization of human urine for specimen validity determination in workplace drug testing. J Anal Toxicol 24(7):579–588CrossRefGoogle Scholar
  11. Creeca CR, Roitberg AE (2006) Theoretical study of the isomerization mechanism of azobenzene and distributed azobenzene derivatives. J Phys Chem A 110:8188–8203.  https://doi.org/10.1021/jp057413c CrossRefGoogle Scholar
  12. Diguet A, Guillermic RM, Baigl D (2009) Photomanipulation of a droplet by the chromocapillary effect. Angew Chem Int 48:9281–9284.  https://doi.org/10.1002/anie.200904868 CrossRefGoogle Scholar
  13. Diguet A, Li H, Queyriaux N, Chen Y, Baigl D (2011) Photreversible fragmentation of a liquid interface for micro droplet generation by light actuation. Lab Chip 11:2666–2669.  https://doi.org/10.1039/c1lc20328b CrossRefGoogle Scholar
  14. Edwards SL (2008) Pathophysiology of acid base balance: the theory practice relationship. Intensive Crit Care Nurs 24:28–40.  https://doi.org/10.1016/j.iccn.2007.05.003 CrossRefGoogle Scholar
  15. Fan SK, Hseih HT, Lin DY (2009) General digital microfluidic platform manipulating dielectric and conductive droplets by dielectrophoresis and electrowetting. Lab Chip 9:1236–1242.  https://doi.org/10.1039/b816535a CrossRefGoogle Scholar
  16. Inui N (2007) Relationship between contact angle of liquid droplet and light beam position in optoelectrowetting. Sens Actuators A 40:123–130.  https://doi.org/10.1016/j.sna.2007.06.001 CrossRefGoogle Scholar
  17. Jin J, Ngyuen NT (2018) Manipulation schemes and applications of liquid marbles for micro total analysis systems. Microelectron Eng 197:87–95.  https://doi.org/10.1016/j.mee.2018.06.003 CrossRefGoogle Scholar
  18. Jin J, Ooi CH, Dao DV, Ngyuen NT (2017) Coalescence processes of droplets and liquid marbles. Micromachines 8:36.  https://doi.org/10.3390/mi8110336 CrossRefGoogle Scholar
  19. Kratz A, Ferraro M, Sluss PM, Lewandrowski KB (2004) Normal reference laboratory values. N Engl J Med 351:1548.  https://doi.org/10.1056/nejmcpc049016 CrossRefGoogle Scholar
  20. Krogmann F, Qu H, Zappe H (2008) Push/pull actuation using opto-electrowetting. Sens Actuators A 141:499–505.  https://doi.org/10.1016/j.sna.2007.08.017 CrossRefGoogle Scholar
  21. Mahimwalla Z, Yager KG, Barett CJ (2012) Azobenzene photomechanics: prospects and potential applications. Polym Bull.  https://doi.org/10.1007/s00289-012-0792-0 CrossRefGoogle Scholar
  22. Marques AV, Barbaud F, Baigl D (2013) Microfluidic mixing triggered by an external LED illumination. J Am Chem Soc 135:3218–3223.  https://doi.org/10.1021/ja311837r CrossRefGoogle Scholar
  23. Merino E, Ribagorda M (2012) Control over molecular motion using the cis-trans photoisomerization of the azo group. Beilstein J Org Chem 8:1071–1090.  https://doi.org/10.3762/bjoc.8.119 CrossRefGoogle Scholar
  24. Naghii MR, Ebrahimpour Y, Darvishi P (2012) Effect of consumption of fatty acids, calcium, vitamin D and boron with regular physical activity on bone mechanical properties and corresponding metabolic hormones in rat. Indian J Exp Biol 50(3):223–231Google Scholar
  25. Oh SK, Nakagawa M, Ichimura K (2002) Photocontrol of liquid motion on an azobenzene monolayer. J Mater Chem 12:2262–2269.  https://doi.org/10.1039/B110825P CrossRefGoogle Scholar
  26. Ooi CH, Jin J, Sreejith KR, Nguyen AH, Evans GM, Nguyen NT (2018a) Manipulation of a floating liquid marble using dielectrophoresis. Lab Chip 18:3770–3779.  https://doi.org/10.1039/c8lc01057a CrossRefGoogle Scholar
  27. Ooi CH, Jin J, Nguyen AH, Evans GM, Nguyen NT (2018b) Picking up and placing a liquid marble using dielectrophoresis. Microfluid Nanofluid 22:142.  https://doi.org/10.1007/s10404-018-2163-0 CrossRefGoogle Scholar
  28. Park SY, Chiou PY (2011) Light driven droplet manipulation technologies for lab on a chip applications. Adv OptoElectron 1:1.  https://doi.org/10.1155/2011/909174 CrossRefGoogle Scholar
  29. Park SY, Kalim S, Callahan C, Chiou PY (2009) A light induced dielectrophoretic droplet manipulation platform. Lab Chip 9:3228–3235.  https://doi.org/10.1039/b909158k CrossRefGoogle Scholar
  30. Persichetti G, Grimaldi IA, Testa G, Bernini R (2017) Mutlifunctional optofluidic lab-on-chip platform for Raman and fluorescence spectroscopic microfluidic analysis. Lab Chip 17:2631–2639.  https://doi.org/10.1039/C7LC00460E CrossRefGoogle Scholar
  31. Rola H, Halabieh EI, Mermut O, Barrett CJ (2004) Using light to control physical properties of polymers and surfaces with azobenzene chromophores. IUPAC Pure Appl Chem 76(7–8):1445–1465.  https://doi.org/10.1351/pac200476071445 CrossRefGoogle Scholar
  32. Tandogan B, Ulusu N (2005) Importance of calcium. Perspect Med Sci 35(1):197–201Google Scholar
  33. Teh SY, Lin R, Lee AP (2008) Droplet microfluidics. Lab Chip 8:198–220.  https://doi.org/10.1039/b715524g CrossRefGoogle Scholar
  34. Thomas T, Unni HN (2018) LED based opto-wetting platforms for micromixing. In: Proceedings of SPIE 10491, microfluidics, bioMEMS, and medical microsystems XVI, 104910R.  https://doi.org/10.1117/12.2290107
  35. Wagner N, Theato P (2014) Light induced wettability changes on polymer surfaces. Polymer 55:3436–3453.  https://doi.org/10.1016/j.polymer.2014.05.033 CrossRefGoogle Scholar
  36. Walker SW, Shapiro B (2006) Modeling the fluid dynamics of electrowetting on dielectric (EWOD). J Microelectromech Syst 15(4):986–1000.  https://doi.org/10.1109/JMEMS.2006.878876 CrossRefGoogle Scholar
  37. Yager KG, Barrett CJ (2006) Novel photoswitching using azobenzene functional material. J Photochem Photobiol A Chem 182:250–261.  https://doi.org/10.1016/j.jphotochem.2006.04.021 CrossRefGoogle Scholar
  38. Yang D, Piech M, Picraux ST (2007) Photon control of liquid motion on reversibly photoresponsive surfaces. Langmuir Am Chem Soc 23:10864–10872.  https://doi.org/10.1021/la701507 CrossRefGoogle Scholar
  39. Zak B, Epstein E, Baginski ES (1975) Review of calcium methodologies. Ann Clin Lab Sci 5(3):195–215Google Scholar
  40. Zhang H, Sun Y (2018) Optofluidic droplet dye laser generated by microfluidic nozzles. Opt Express 26:11284–11291.  https://doi.org/10.1364/OE.26.011284 CrossRefGoogle Scholar
  41. Zhao W, Wu C-X (1999) Rate equation theory of azobenzene monolayer photoisomerization. Chem Phy Lett 312:572–577.  https://doi.org/10.1016/S0009-2614(99)00988-4 CrossRefGoogle Scholar
  42. Zhou YN, Jin Li J, Zhang Q, Luo ZH (2014) Light responsive smart surface with controllable wettability and excellent stability. Langmuir 30:12236–12242.  https://doi.org/10.1021/la501907w CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Biomedical EngineeringIndian Institute of Technology Hyderabad (IIT Hyderabad)SangareddyIndia

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