Miniaturization of Hydrocyclones by High‐Resolution 3D Printing for Rapid Microparticle Separation

Abstract

principles of operation. [10][11][12] However, the effective separation of micron-scale components from biological matrices using these conventional techniques is often constrained by low throughput, biofouling, and incompatibility with the need for continuous and automated processing. [3,6,7,9] In addition, biological particles such as cells are often susceptible to damage or degradation due to the application of high forces during centrifugal or membrane based separations, presenting a further obstacle to achieving time-and cost-effective isolation of biological targets. [3,[13][14][15][16][17][18] Microfluidic-based separations based on both active and passive techniques have been investigated as promising approaches to continuous-flow isolation of micron-scale particles from fluid suspensions. Active separation methods utilize external forces including electric, [19] magnetic, [20] and acoustic forces, [21] whereas passive separation methods utilize hydrodynamic forces induced by microstructure-fluid interactions and fluid dynamic phenomena. [22][23][24] Passive separations are particularly attractive as they do not require external actuation beyond the application of bulk fluid flow through the system, thereby minimizing instrumentation requirements and system complexity. Microfluidic filtration is a straightforward strategy for particle separation utilizing sizebased retention, with an integrated membrane, micropillar array, or other porous structure able to selectively pass particles smaller than the pore size while retaining other larger particles. [25][26][27] However, as with its macroscale counterpart, filtration presents inherent challenges when handling large sample volumes, including membrane biofouling, limited throughput, high pressure requirements, and limited scaling. [26,[28][29][30] While passive hydrodynamic separation techniques such as inertial focusing, [24,31] deterministic lateral displacement, [32,33] pinched flow fractionation, [34] and Dean flow focusing [22,35,36] can overcome these constraints and are well suited to continuous flow operation, throughput remains fundamentally limited since relatively low Reynolds number flows must be employed in these systems to maintain force balance during microfluidic separations. [23,30,37] At the macroscale, hydrocyclone technology has evolved as a powerful and simple solid-liquid separation technology traditionally used in large-volume industrial processes including mineral dewatering [38,39] and desliming, [40] heavy metal recovery, [41,42] and water treatment. [43][44][45] Hydrocyclones enable Hydrocyclones are a simple and powerful particle separation technology, widely used in macroscale industrial processes, with enormous potential for miniaturization. Although recent efforts to shrink hydrocyclones to the centimeter scale have shown great promise for passive and high-throughput microparticle separations, further miniaturization is constrained by limited understanding of the impact of device size scale and design on separation performance,...

Microfluidic vortex focusing for high throughput synthesis of size-tunable liposomes

“…Devices were fabricated using a high resolution SLA-DLP process leveraging our work on 3D printed microscale hydrocyclones for particle separation and concentration 62 . Overall device dimensions were identical to this prior study, including total chamber diameter and length of 1.5 mm and 8.4 mm, respectively, vortex formation gap of 300 µm, and inlet/outlet channel diameters of 300 µm.…”

“…Hydrocyclone technology, originally developed for continuous-flow particle separations, employs an inverted conical chamber with a tangential sample inlet adjacent to the cone base to generate a rotating fluid vortex that entrains particles within size-dependent streamlines, such that smaller particles are routed to an upper axial outlet at the base of the inverted cone while larger particles are routed to a lower axial outlet at the cone apex 56,57 . Miniature hydrocyclones with critical dimensions ranging from several millimeters [58][59][60] to several hundred micrometers 61 have recently been explored to reduce the achievable particle cut size, including efforts by our own group to develop small-scale hydrocyclones by additive manufacturing 62 . Here we employ a miniature cyclone with 300 µm critical dimensions to achieve nanoscale liposome synthesis by modifying the lipid sample and buffer flow paths within the device.…”

Microfluidic Platforms for the Production of Nanoparticles at Flow Rates Larger Than One Liter Per Hour

“…This flow geometry had been formerly designed as a microscale hydro‐cyclone for particle separations. [ 54 ] The device was prototyped by stereolithography 3D‐printing (Figure 4b) and proven to produce liposomes with a narrow size distribution, with particle diameters as small as 27 nm at the TFR of 4.8 l h −1 .…”

Vat Photopolymerization 3D Printing of Advanced Soft Sensors and Actuators: From Architecture to Function

“…developed a microscale hydrocyclone with critical feature size as small as 250 µm, which is able to separate particles as small as 3.7 µm, by taking advantages of 3D printing using SLA coupled with DLP. [ 129 ] VP breaks through the limitation of using traditional microfabrication technology to realize the internal helical structure of hydrocyclone and guarantee the separation performance of the device. Figure a shows a representative 3D‐printed microfluidic device, which has a hydrodynamic focusing chamber with a focusing junction to achieve streams selectively passing through and realize the particle‐by‐particle counting.…”