Continuous enrichment of low-abundance cell samples using standing surface acoustic waves (SSAW)

Abstract

Cell enrichment is a powerful tool in a variety of cellular studies, especially in applications with low-abundance cell types. In this work, we developed a standing surface acoustic wave (SSAW) based microfluidic device for non-contact, continuous cell enrichment. With a pair of parallel interdigital transducers (IDT) deposited on a piezoelectric substrate, a one-dimensional SSAW field was established along disposable micro-tubing channels, generating numerous pressure nodes (and thus numerous cell-enrichment regions). Our method is able to concentrate highly diluted blood cells by more than 100 fold with a recovery efficiency of up to 99%. Such highly effective cell enrichment was achieved without using sheath flow. The SSAW-based technique presented here is simple, bio-compatible, label-free, and sheath-flow-free. With these advantages, it could be valuable for many biomedical applications.

Radiation dominated acoustophoresis driven by surface acoustic waves

“…Therefore, surface acoustic wave (SAW) transducers have gained significant attention due to its easy integration with soft polymer-based microfluidic devices [12,13]. SAW-based particle manipulation has been successfully applied for focusing [14,15], separation [16][17][18][19][20][21][22], patterning [23][24][25], and enrichment [26] of particles or biological cells for various microfluidic applications. In these applications, acoustic streaming effect is typically minimized to implement acoustic radiation dominated particle manipulation.…”

Simultaneous diamagnetic and magnetic particle trapping in ferrofluid microflows via a single permanent magnet

“…5,6 More preferably, particles can be captured in a flowing suspension through the use of an external force, where the accumulated particles can be readily dispersed by either lowering (or switching off) the force field or increasing the flow rate. [2][3][4] A number of non-magnetic force fields, 1,7 including acoustic, 8,9 electric, [10][11][12][13] and optical [14][15][16] forces, have been demonstrated to enrich various types of particles and cells in microfluidic devices. Compared to these contactless methods, magnetic trapping of particles has several advantages such as low cost, heating free (except for electromagnets), and near independence of the suspending medium properties (e.g., ionic concentration and pH value).…”

Acoustofluidic waveguides for localized control of acoustic wavefront in microfluidics

“…Acoustofluidic-based particle/cell manipulation methods exhibit several unique advantages over their optical, electrical, and magnetic counterparts (Suri et al 2013; Voldman 2006; Zhang and Liu 2008). They are simple, noninvasive, contactless, and label-free (Ahmed et al 2016; Bruus 2011, 2012b; Chen et al 2013, 2014, 2016; Collins et al 2015, 2016; Ding et al 2012a; Gedge and Hill 2012; Glynne-Jones et al 2012; Goddard et al 2006, 2007; Guldiken et al 2012; Guo et al 2015a, b, c, 2016; Huang et al 2013; Li et al 2015; Mao et al 2016; Ren et al 2015; Shi et al 2009a, b; Tang et al 2016; Wang and Zhe 2011). Among the wide range of applications enabled by acoustofluidic technologies, capturing, patterning, and retaining of biological cells and microparticles in an ordered arrangement is of particular interest as it is of fundamental importance for fields such as microarrays (Flaim et al 2005; Gresham et al 2008), regenerative medicine (Khetani and Bhatia 2008; Smith 2007), 3D bio-printing (Kolesky et al 2014; Murphy and Atala 2014), intercellular communications (Van Nhieu et al 2003; You et al 2004), as well as tissue engineering (Ashkin et al 1987; Puleo et al 2007).…”