Latest Updates on the Advancement of Polymer-Based Biomicroelectromechanical Systems for Animal Cell Studies

Table 2

Recent BioMEMS platforms for cell separation including the type of the platform, the main components, the fabrication strategy, the mechanism of operation, and the specifics of each platform.

BioMEMS platform	Main components	Fabrication strategy	Mechanism of operation	Specifics	Ref.
Noninertial hydrodynamic lift-induced cell sorting device	Syringe pumps; Microfluidic chip; Voltage source	Standard soft lithography	The separation process took advantage of size and deformability as intrinsic biomarkers were induced by a hydrodynamic effect at very low Re, separating the target cells by their size.	The device is capable of sorting MV3-melanoma cells from an RBC suspension at a high hematocrit level.; The mechanism of sorting is gentle compared to other label-free techniques.	[22]
Parsortix™ system for cell capture	Plastic molding containing a stepped separation structure and microchannels; Heat-bonded thin plastic cover		The system used a microfluidic cassette that captured cells based on their size and deformability.; The sample passes through a fluidic path leading to flow distribution channels and over the stepped separator.	Cell size must be known for the system to be able to capture them.; The device does not depend on antibody affinity.	[23]
Continuous-flow microfluidic DEP chip	Oblique interdigitated electrode array; AC frequency generator; Syringe pumps; Microfluidic chip		The devices used DEP to force the target cells to flow in a determined path.	The device facilitated the continuous label-free cell separation.	[25]
Paper-based extraction device	Paper-based valve; Sponge-based buffer storage	3D printing using a photopolymer resin	Separation was achieved by the combination of high affinity between the negatively charged particles of interest and the positively charged glass fiber.	The device can be used in resource-limited settings.	[87]
Microfluidic chip with a ratchet mechanism coupled with a hydrodynamic concentrator	2D microscale funnel membrane-based; Microvalves	Standard PDMS multilayer soft lithography fabrication techniques	The device used oscillatory flow to manipulate cancer cells and leukocytes and performed a throughput separation.	The device has the ability to refresh the filter microstructure after each separation.	[88]
Inertial focusing LOC	Rectangular microchannel; Serpentine microchannels; Fluidic resistors	Standard soft lithography techniques with PDMS	The device operated a high-throughput separation by multichannel shape-based sorting of the microalga using inertial focusing techniques.	The device is cost-effective and label-free.	[95]
Elasto-inertial pinched flow fractionation microfluidic platform	Asymmetric T-shaped microchannels; Syringe pumps		Continuous separation of particles of equal volume by exploiting the elasto-inertial lift-induced particle viscoelastic fluids. The device uses particle’s rotational movements controlled by the zig-zag shape of the induced microchannel.	The device offered a label-free separation.	[96]
Polymer-film inertial microfluidic jigsaw sorter	A trapezoidal spiral inertial microfluidic sorter chip; Syringe pump	Laser cutting; Plasma-activated bonding	The device utilized a syringe pump to inject the cell suspension at specific flow rates. The cells were separated by inertial forces and recovered in different outlets.	The device demonstrates a complete separation of the binary particles with a minimum size difference of 2 μm. The device was successfully applied for the separation of rare CTCs from the blood samples.	[26]
3D printed inertial microfluidic device	3D printed device; PMMA sheet; Syringe pump	DLP 3D printing; Pressure-sensitive adhesive bonding	The device utilized the inertial forces to separate different cell lines.	Through this strategy, fabrication of a right-angled triangular cross-section was possible.	[27]
Acoustofluidic chip for nano/microparticle separation	PDMS-based chip; SAW transducer; Function generator; Amplifier Syringe pump	Photolithography; Standard soft lithography techniques with PDMS	Hydrodynamic focusing was applied allowing particles to enter consistently into the same position in the acoustic field, and once the SAW field was applied, particles were deflected and separated into different streams.	Particles with a wide size range from 200 nm to 10 μm can be separated with this device.	[28]

CTCs: circulating tumor cells; DEP: dielectrophoresis; DLP: digital light processing; LOC: Lab-on-a-Chip; PDMS: polydimethyl siloxane; PMMA: poly(methyl methacrylate); RBCs: red blood cells; Re: Reynolds number; SAW: surface acoustic wave ; 3D: three-dimensional; 2D: two-dimensional.