Benchmarking a Microfluidic-Based Filtration for Isolating Biological Particles

Abstract

Isolating particles from complex fluids is a crucial approach in multiple fields including biomedicine. In particular, biological matrices contain a myriad of distinct particles with different sizes and structures. Extracellular vesicles (EVs), for instance, are nanosized particles carrying vital information from donor to recipient cells, and they have garnered significant impact on disease diagnostics, drug delivery, and theranostics applications. Among all the EV types, exosome particles are one of the smallest entities, sizing from 30 to 100 nm. Separating such small substances from a complex media such as tissue culture and serum is still one of the most challenging steps in this field. Membrane filtration is one of the convenient approaches for these operations; yet clogging, low-recovery, and high fouling are still major obstacles. In this study, we design a two-filter-integrated microfluidic device focusing on dead-end and cross-flow processes at the same time, thereby minimizing any interfering factors on the recovery. The design of this platform is also numerically assessed to understand pressure-drop and flow rate effects over the procedure. As a model, we isolate exosome particles from human embryonic kidney cells cultured in different conditions, which also mimic complex fluids such as serum. Moreover, by altering the flow direction, we refresh the membranes for minimizing clogging issues and benchmark the platform performance for multitime use. By comprehensively analyzing the design and operation parameters of this platform, we address the aforementioned existing barriers in the recovery, clogging, and fouling factors, thereby achieving the use of a microfluidic device multiple times for bio-nanoparticle isolation without any notable issues.

Recent microfluidic advances in submicron to nanoparticle manipulation and separation

“…Passive microfluidic techniques utilise intrinsic hydrodynamic forces and channel geometry for particle manipulation. The reported passive microfluidic technologies for submicron and nanoparticle separation include inertial microfluidics, [179][180][181][182] deterministic lateral displacement, [183][184][185] microfluidic filtration, [186][187][188] pinched flow fractionation, 189,190 and viscoelastic microfluidics. [191][192][193]…”

“…216 (E) Integrated double-filtration microfluidic device for isolation of exosomes. 187 (F) Size-selective filtration of EVs with a movable plunger and rotational chip. 224 (G) Microfluidic PFF for separation of exosomes and apoptotic bodies.…”

“…4(E). 187 The sample was injected through the first 200 nm pore membrane as dead-end filtration to eliminate large debris. Next, a second 50 nm pore membrane trapped exosomes through a tangential flow strategy.…”

“…(D) Tuning of 100 nm, 200 nm and 500 nm polystyrene bead trajectories using an electrokinetic DLD microfluidic device 216. (E) Integrated double-filtration microfluidic device for isolation of exosomes 187. (F) Size-selective filtration of EVs with a movable plunger and rotational chip 224.…”

The Use of Sensors in Blood-Brain Barrier-on-a-Chip Devices: Current Practice and Future Directions

“…The application of biosensors utilizing the synergistic interaction of electric and optical phenomena can also be advantageous in BBB research, especially when the concentration of penetrating cells or secreted extracellular vesicles are supposed to be quantified [ 60 ]. For the rapid separation of extracellular vesicles according to size, simple filter-based chip modules appear to be the optimal choice [ 104 ], while their proteomic and genomic analysis can be carried out with coupled sensing or amplifying units [ 105 , 106 ]. An interesting new concept suggests the use of in vitro companion biomarker diagnostic devices through all the phases of drug development from preclinical tests to clinical studies in Alzheimer’s disease precision medicine [ 107 ].…”