Rapid large area fabrication of multiscale through-hole membranes

Abstract

There are many proposed mechanisms by which single cells can be trapped; among them is the through-hole membrane for the characterization of individual microorganisms. Due to the small scale of the fabricated pores, the construction of through-hole membranes on a large scale and with relatively large areas faces many difficulties. This paper describes novel fabrication methods for a large-area, freestanding micro/nano through-hole membrane constructed from versatile membrane materials using through-hole membranes on a microfluidic chip (THMMC). This process can rapidly (<20 min) fabricate membranes with high fidelity multiscale hole size without residual layers. The through-hole site was easily customizable from the micro to the nanoscale, with a low or high aspect ratio giving rise to reliable membranes. Also, the rigidity and biocompatibility of the through-hole membrane are easily tunable by simple injection of versatile membrane materials to obtain a large area (up to 3600 mm). Membranes produced in this manner were then applied as a proof of concept for the isolation, cultivation, and quantification of individual micro-algal cells for selection with respect to the growth rate, while controlling the quorum sensing mediated metabolic and proliferative changes.

Effect of pore geometry on nanoconfined water transport behavior

“…[17][18][19] Meanwhile, it should be noted that various pore cross-sections will be inevitably encountered as there are some mature industries utilizing natural material preferentially, rather than alternative artificial materials with regular circular nanopores. 20,21 Thus, the necessity to shed light on water transport behavior through nanopores with irregular pore shapes emerges. Furthermore, the man-made material with circular nanopores may experience structure deformation after years of use and wear, as a result, pore geometry of which will also turn to irregular type.…”

Flat and microstructured polymeric membranes in organs-on-chips

“…These proteins contain amino acid sequences like arginine-glycine-aspartic acid (RGD), which are potent sites for cell adhesion [54,55]. Cells interact with these sites via integrins, transmembrane proteins [6] erythrocyte oxygenation [7] gut [1,18,19] heart [40] kidney [13] liver [1,3,13,38] lung [1,11,13,42] multi-organ-on-chip (MOC) of liver and heart [47] new membranes for OOCs [52] poly(carbonate) (PC) blood -brain barrier (BBB) [4,43,44] bonding of membrane to chip [51] colon and breast cancer [27] gut [8,9] gut, liver and brain cancer [16] MOC of liver and intestine [29] MOC of liver and skin [29] multiple-layered cultures of fibroblasts, endothelial and mesenchymal cells [41] liver, lung and breast cancer and gut [25] skin [5,23] poly(ethylene terephthalate) (PET) gut [39] heart [28] kidney [15] liver [17,48] microfluidic barrier tissues [2] MOC of liver and cancer [21] white adipose tissue (fat) [26] aliphatic polyesters poly(lactic acid) (PLA) endothelial barrier [33] poly ( liver…”

“…new membranes for OOCs [52] rsif.royalsocietypublishing.org J. R. Soc. Interface 15: 20180351 which can also link to the actin cytoskeleton of the cells.…”

Large-scale fabrication of free-standing and sub-μm PDMS through-hole membranes

“… 25 Based on the dewetting of resins into a hierarchical mold, nanomembranes with various nano through-hole sizes from 50 nm to 800 nm, and shapes (dots or lines) were fabricated. By combining hierarchical structures with a microfluidic chip, Tahk et al 26 reported an alternative fabrication method for patterning multiscale PDMS through-hole membranes. Their chip was fabricated by plasma, bonding the top part of a microfluidic chip made of PDMS with a nanocolumn patterned substrate.…”

“…By gently separating the chip bonding via cutting, sub-μm PDMS membranes with nano through-holes were peeled off from the PDMS chip. Although being able to fabricate free-standing and through-hole nanomembranes, these fabrication methods 25 , 26 require hierarchical molds consisting of patterned nanocolumns. Patterning such molds is labor intensive, and requires dedicated patterning systems which are expensive.…”