Assessment of silicon, glass, FR4, PDMS and PMMA as a chip material for acoustic particle/cell manipulation in microfluidics

• Published in: Ultrasonics Vol. 129; p. 106911
• Main Authors: Açıkgöz, Hande N., Karaman, Alara, Şahin, M. Akif, Çaylan, Ömer R., Büke, Göknur C., Yıldırım, Ender, Eroğlu, İrem C., Erson-Bensan, A. Elif, Çetin, Barbaros, Özer, M. Bülent
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2023
• Subjects: Acoustics; Acoustofluidics; Cultured cancer cells; Dimethylpolysiloxanes; FR4; Microfluidics; Piezoelectric actuators; Polymethyl Methacrylate; Silicon; Ultrasonics; Vibrations; Vibrations; FR4; Cultured cancer cells; Acoustofluidics; Piezoelectric actuators; Ultrasonics
• ISSN: 0041-624X; 1874-9968
• DOI: 10.1016/j.ultras.2022.106911

In the present study, the capabilities of different chip materials for acoustic particle manipulation have been assessed with the same microfluidic device architecture, under the same actuator and flow conditions. Silicon, glass, epoxy with fiberglass filling (FR4), polydimethylsiloxane (PDMS) and polymethyl methacrylate (PMMA) are considered as chip materials. The acoustophoretic chips in this study were manufactured with four different fabrication methods: plasma etching, chemical etching, micromachining and molding. A novel chip material, FR4, has been employed as a microfluidic chip material in acoustophoretic particle manipulation for the first time in literature, which combines the ease of manufacturing of polymer materials with improved acoustic performance. The acoustic particle manipulation performance is evaluated through acoustophoretic focusing experiments with 2μm and 12μm polystyrene microspheres and cultured breast cancer cell line (MDA-MB-231). Unlike the common approach in the literature, the piezoelectric materials were actuated with partitioned cross-polarized electrodes which allowed effective actuation of different family of chip materials. Different from previous studies, this study evaluates the performance of each acoustophoretic device through the perspective of synchronization of electrical, vibrational and acoustical resonances, considers the thermal performance of the chip materials with their effects on cell viability as well as manufacturability and scalability of their fabrication methods. We believe our study is an essential work towards the commercialization of acoustophoretic devices since it brings a critical understanding of the effect of chip material on device performance as well as the cost of achieving that performance. •Selection of chip material is critical in micro-acoustofluidics.•Manipulation performance of several different chip materials are investigated.•FR4 chip material combines the advantages of polymer acoustically hard chip materials.•For the first time in the literature, the effect of choice of chip material isF investigated through electrical, vibration, thermal and cell viability perspectives as well as ease of manufacturing and scalability.