Monolithic digital patterning of polydimethylsiloxane with successive laser pyrolysis

Abstract

The patterning of polydimethylsiloxane (PDMS) into complex two-dimensional (2D) or 3D shapes is a crucial step for diverse applications based on soft lithography. Nevertheless, mould replication that incorporates time-consuming and costly photolithography processes still remains the dominant technology in the field. Here we developed monolithic quasi-3D digital patterning of PDMS using laser pyrolysis. In contrast with conventional burning or laser ablation of transparent PDMS, which yields poor surface properties, our successive laser pyrolysis technique converts PDMS into easily removable silicon carbide via consecutive photothermal pyrolysis guided by a continuous-wave laser. We obtained high-quality 2D or 3D PDMS structures with complex patterning starting from a PDMS monolith in a remarkably low prototyping time (less than one hour). Moreover, we developed distinct microfluidic devices with elaborated channel architectures and a customizable organ-on-a-chip device using this approach, which showcases the potential of the successive laser pyrolysis technique for the fabrication of devices for several technological applications.

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Fig. 1: Mechanisms of two SLP process schemes.
Fig. 2: Quantitative analysis of SLP.
Fig. 3: Demonstrative fabrication of representative PDMS devices.
Fig. 4: Fabrication of a biocompatible organ-on-a-chip model by SLP.

Data availability

The authors declare that all data supporting the findings of this study are available within the main text and Supplementary Information. Source data for the figures are available at https://doi.org/10.6084/m9.figshare.12601793.

References

  1. 1.

    Xia, Y. & Whitesides, G. M. Soft lithography. Angew. Chem. Int. Ed. Engl. 37, 550–575 (1998).

    CAS  Article  Google Scholar 

  2. 2.

    McDonald, J. C. & Whitesides, G. M. Poly(dimethylsiloxane) as a material for fabricating microfluidic devices. Acc. Chem. Res. 35, 491–499 (2002).

    CAS  Article  Google Scholar 

  3. 3.

    Sia, S. K. & Whitesides, G. M. Microfluidic devices fabricated in poly(dimethylsiloxane) for biological studies. Electrophoresis 24, 3563–3576 (2003).

    CAS  Article  Google Scholar 

  4. 4.

    Thorsen, T., Maerkl, S. J. & Quake, S. R. Microfluidic large-scale integration. Science 298, 580–584 (2002).

    CAS  Article  Google Scholar 

  5. 5.

    Huh, D. et al. Reconstituting organ-level lung functions on a chip. Science 328, 1662–1668 (2010).

    CAS  Article  Google Scholar 

  6. 6.

    Huh, D. et al. Microfabrication of human organs-on-chips. Nat. Protocols 8, 2135–2157 (2013).

    CAS  Article  Google Scholar 

  7. 7.

    Ko, S. H. et al. Direct nanoimprinting of metal nanoparticles for nanoscale electronics fabrication. Nano Lett. 7, 1869–1877 (2007).

    CAS  Article  Google Scholar 

  8. 8.

    Bhattacharjee, N., Urrios, A., Kang, S. & Folch, A. The upcoming 3D-printing revolution in microfluidics. Lab Chip 16, 1720–1742 (2016).

    CAS  Article  Google Scholar 

  9. 9.

    Choi, K. M. & Rogers, J. A. A photocurable poly(dimethylsiloxane) chemistry designed for soft lithographic molding and printing in the nanometer regime. J. Am. Chem. Soc. 125, 4060–4061 (2003).

    CAS  Article  Google Scholar 

  10. 10.

    Coenjarts, C. A. & Ober, C. K. Two-photon three-dimensional microfabrication of poly(dimethylsiloxane) elastomers. Chem. Mater. 16, 5556–5558 (2004).

    CAS  Article  Google Scholar 

  11. 11.

    Bhattacharjee, N., Parra-Cabrera, C., Kim, Y. T., Kuo, A. P. & Folch, A. Desktop-stereolithography 3D-printing of a poly(dimethylsiloxane)-based material with Sylgard-184 properties. Adv. Mater. 30, e1800001 (2018).

    Article  Google Scholar 

  12. 12.

    Wolfe, D. B. et al. Customisation of poly(dimethylsiloxane) stamps by micromachining using a femtosecond-pulsed laser. Adv. Mater. 15, 62–65 (2003).

    CAS  Article  Google Scholar 

  13. 13.

    Liu, H. B. & Gong, H. Q. Templateless prototyping of polydimethylsiloxane microfluidic structures using a pulsed CO2 laser. J. Micromech. Microeng. 19, 037002 (2009).

    Article  Google Scholar 

  14. 14.

    Marcinkevi Ius, A. et al. Femtosecond laser-assisted three-dimensional microfabrication in silica. Opt. Lett. 26, 277–279 (2001).

    CAS  Article  Google Scholar 

  15. 15.

    Cheng, Y., Sugioka, K. & Midorikawa, K. Microfluidic laser embedded in glass by three-dimensional femtosecond laser microprocessing. Opt. Lett. 29, 2007–2009 (2004).

    Article  Google Scholar 

  16. 16.

    Liao, Y. et al. Three-dimensional microfluidic channel with arbitrary length and configuration fabricated inside glass by femtosecond laser direct writing. Opt. Lett. 35, 3225–3227 (2010).

    Article  Google Scholar 

  17. 17.

    Cho, S. H., Chang, W. S., Kim, K. R. & Hong, J. W. Femtosecond laser embedded grating micromachining of flexible PDMS plates. Opt. Commun. 282, 1317–1321 (2009).

    CAS  Article  Google Scholar 

  18. 18.

    Liu, H. B. & Gong, H. Q. Templateless prototyping of polydimethylsiloxane microfluidic structures using a pulsed CO2 laser. J. Micromech. Microeng. 19, 037002 (2009).

    Article  Google Scholar 

  19. 19.

    Li, M. et al. A simple and cost-effective method for fabrication of integrated electronic-microfluidic devices using a laser-patterned PDMS layer. Microfluid. Nanofluid. 12, 751–760 (2012).

    CAS  Article  Google Scholar 

  20. 20.

    Yang, H., Deschatelets, P., Brittain, S. T. & Whitesides, G. M. Fabrication of high performance ceramic microstructures from a polymeric precursor using soft lithography. Adv. Mater. 13, 54–58 (2001).

    Article  Google Scholar 

  21. 21.

    Hidai, H., Yoshioka, M., Hiromatsu, K. & Tokura, H. Glass modification by continuous-wave laser backside irradiation (CW-LBI). Appl. Phys. A 96, 869–872 (2009).

    CAS  Article  Google Scholar 

  22. 22.

    Nakajima, Y., Hayashi, S., Katayama, A., Nedyalkov, N. & Terakawa, M. Femtosecond laser-based modification of PDMS to electrically conductive silicon carbide. Nanomaterials 8, 558 (2018).

    Article  Google Scholar 

  23. 23.

    Huan, H. & Zhixiong, G. Ultra-short pulsed laser PDMS thin-layer separation and micro-fabrication. J. Micromech. Microeng. 19, 055007 (2009).

    Article  Google Scholar 

  24. 24.

    Wang, Z. K., Zheng, H. Y., Lim, R. Y. H., Wang, Z. F. & Lam, Y. C. Improving surface smoothness of laser-fabricated microchannels for microfluidic application. J. Micromech. Microeng. 21, 095008 (2011).

    Article  Google Scholar 

  25. 25.

    Minerick, A. R., Ostafin, A. E. & Chang, H.-C. Electrokinetic transport of red blood cells in microcapillaries. Electrophoresis 23, 2165–2173 (2002).

    CAS  Article  Google Scholar 

  26. 26.

    Bahrami, M., Yovanovich, M. M. & Culham, J. R. Pressure drop of fully developed, laminar flow in rough microtubes. J. Fluids Eng. 128, 632–637 (2005).

    Article  Google Scholar 

  27. 27.

    Yang, S. C. Effects of surface roughness and interface wettability on nanoscale flow in a nanochannel. Microfluid. Nanofluid. 2, 501–511 (2006).

    CAS  Article  Google Scholar 

  28. 28.

    Heng, Q., Tao, C. & Tie-chuan, Z. Surface roughness analysis and improvement of micro-fluidic channel with excimer laser. Microfluid. Nanofluid. 2, 357–360 (2006).

    Article  Google Scholar 

  29. 29.

    Unger, M. A., Chou, H. P., Thorsen, T., Scherer, A. & Quake, S. R. Monolithic microfabricated valves and pumps by multilayer soft lithography. Science 288, 113–116 (2000).

    CAS  Article  Google Scholar 

  30. 30.

    Gerlach, A. et al. Microfabrication of single-use plastic microfluidic devices for high-throughput screening and DNA analysis. Microsyst. Technol. 7, 265–268 (2002).

    Article  Google Scholar 

  31. 31.

    Rötting, O., Röpke, W., Becker, H. & Gärtner, C. Polymer microfabrication technologies. Microsyst. Technol. 8, 32–36 (2002).

    Article  Google Scholar 

  32. 32.

    Campo, A. D. & Greiner, C. SU-8: a photoresist for high-aspect-ratio and 3D submicron lithography. J. Micromech. Microeng. 17, R81–R95 (2007).

    Article  Google Scholar 

  33. 33.

    Chen, C., Hirdes, D. & Folch, A. Gray-scale photolithography using microfluidic photomasks. Proc. Natl Acad. Sci. USA 100, 1499–1504 (2003).

    CAS  Article  Google Scholar 

  34. 34.

    Jeon, N. L. et al. Generation of solution and surface gradients using microfluidic systems. Langmuir 16, 8311–8316 (2000).

    CAS  Article  Google Scholar 

  35. 35.

    Cacucciolo, V. et al. Stretchable pumps for soft machines. Nature 572, 516–519 (2019).

    CAS  Article  Google Scholar 

  36. 36.

    Mishra, A. K. et al. Autonomic perspiration in 3D-printed hydrogel actuators. Sci. Robot. 5, eaaz3918 (2020).

    Article  Google Scholar 

  37. 37.

    Toepke, M. W. & Beebe, D. J. PDMS absorption of small molecules and consequences in microfluidic applications. Lab Chip 6, 1484–1486 (2006).

    CAS  Article  Google Scholar 

  38. 38.

    Regehr, K. J. et al. Biological implications of polydimethylsiloxane-based microfluidic cell culture. Lab Chip 9, 2132–2139 (2009).

    CAS  Article  Google Scholar 

  39. 39.

    Su, X. et al. Microfluidic cell culture and its application in high-throughput drug screening: cardiotoxicity assay for hERG channels. J. Biomol. Screen. 16, 101–111 (2011).

    CAS  Article  Google Scholar 

  40. 40.

    Hinson, J. T. et al. Titin mutations in iPS cells define sarcomere insufficiency as a cause of dilated cardiomyopathy. Science 349, 982–986 (2015).

    CAS  Article  Google Scholar 

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Acknowledgements

This work is supported by the National Research Foundation of Korea (NRF) Grant funded through the Basic Science Research Program (2017R1A2B3005706, 2018R1A2A1A05019550).

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Authors

Contributions

J.S. and S.J. prepared the samples with the assistance of P.W., Y.L. and J.Kim. S.H. assisted in analysing the data and improving the discussion. J.Ko designed the biochip and conducted cell culture experiments. J.S. and S.H.K. developed the SLP concept and wrote the manuscript. N.L.J. and S.H.K. supervised the overall project. All the authors contributed to the discussion and preparation of the manuscript.

Corresponding authors

Correspondence to Noo Li Jeon or Seung Hwan Ko.

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The authors declare no competing interests.

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Supplementary information

Supplementary Information

Supplementary Notes 1–11, Methods 1–3, Figs. 1–33, Tables 1–5 and refs 1–90.

Reporting Summary

Supplementary Video 1

Initiation and progression.

Supplementary Video 2

Onset of pyrolysis.

Supplementary Video 3

SiC cleaning.

Supplementary Video 4

Demonstration: concentration gradient generator.

Supplementary Video 5

Demonstration: skin-on-a-chip.

Supplementary Video 6

Demonstration: perfusable cell-bed.

Supplementary Video 7

Demonstration: MN array mould.

Supplementary Video 8

Medium through-put manufacturing (vasculature-on-a-chip).

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Shin, J., Ko, J., Jeong, S. et al. Monolithic digital patterning of polydimethylsiloxane with successive laser pyrolysis. Nat. Mater. (2020). https://doi.org/10.1038/s41563-020-0769-6

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