A practical and cost-effective method to make permanently bonded acoustofluidic chips reconfigurable

Kuruoğlu F.

Microfluidics and Nanofluidics, vol.26, no.9, 2022 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 9
  • Publication Date: 2022
  • Doi Number: 10.1007/s10404-022-02579-3
  • Journal Name: Microfluidics and Nanofluidics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Biotechnology Research Abstracts, Compendex, INSPEC
  • Keywords: Acoustofluidic, Bond-detach, KOH, Lithium niobate, PDMS
  • Istanbul University Affiliated: Yes


© 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Acoustofluidic devices that save space and cost are promising for in-situ diagnosis and also the prognosis of many diseases including bacterial infections and cancer. Acoustofluidic devices owe their merit to the combined use of two functional materials, usually lithium niobate and polydimethylsiloxane. While the permanent bonding between lithium niobate-based surface acoustic wave chips and polydimethylsiloxane-based microchannel gives a wide range of functionality, it inevitably limits such devices to single-purpose use where versatility is absent. Here, a bond-detach procedure was demonstrated as a practical and cost-efficient method that enables design modification either in a lithium niobate chip or microchannel. Hence, by simply replacing either constituent, modified acoustofluidic devices targeted for different microbody types or sizes can be realized. The proposed approach to detach permanently bonded acoustofluidic devices via oxygen plasma treatment is based on immersing the devices in 0.1 M potassium hydroxide solution for two hours. It is clearly seen that the bond-detach procedure can be applied at least three times without any significant deterioration in either piezoelectric surface or microfluidic channel in terms of mechanical, optical and chemical properties. Moreover, no significant shift or attention was observed in the transmission spectra of interdigital transducers pairs after the application of the procedure three times. The proposed approach can help durability and reusability of acoustofluidic devices against factors such as clogging, and mechanical or chemical degradation. Graphical abstract: [Figure not available: see fulltext.]