Use of porous membranes in tissue barrier and co-culture models

Abstract

Porous membranes enable the partitioning of cellular microenvironments in vitro, while still allowing physical and biochemical crosstalk between cells, a feature that is often necessary for recapitulating physiological functions. This article provides an overview of the different membranes used in tissue barrier and cellular co-culture models with a focus on experimental design and control of these systems. Specifically, we discuss how the structural, mechanical, chemical, and even the optical and transport properties of different membranes bestow specific advantages and disadvantages through the context of physiological relevance. This review also explores how membrane pore properties affect perfusion and solute permeability by developing an analytical framework to guide the design and use of tissue barrier or co-culture models. Ultimately, this review offers insight into the important aspects one must consider when using porous membranes in tissue barrier and lab-on-a-chip applications.

Robust and Gradient Thickness Porous Membranes forIn VitroModeling of Physiological Barriers

“…[6] Literature indicates that porous membranes are an essential component for compartmentalized cell co-cultures and to support a tissue barrier. [6][7][8][9][10][11][12][13][14][15] However, most barrier models incorporate commercially available track-etched membranes such as those found in transwell, fiber-based, or micro-fluidic systems with a high thickness compared to the basal laminae in vivo (>10 µm vs. ~300 nm). By using available materials, the porosity cannot be adequately engineered, leading to low porosity, random pore distribution, and limited size control, potentially biasing physiological multi-cellular interplay, especially during co-culture conditions.…”

Use of Nanosphere Self-Assembly to Pattern Nanoporous Membranes for the Study of Extracellular Vesicles

“…The thickness of these membranes is not trivial given the fact that in filtration devices designed for nanoscale species the small pores inherently increase the fluid resistance across the membrane. 34 High permeability, at the nanoscale, can be obtained through membranes with a pore size to thickness ratio close to one. 34,35 Such platform should provide ultrathin membranes with close control on pore size over the range of small EVs.…”

“…34 High permeability, at the nanoscale, can be obtained through membranes with a pore size to thickness ratio close to one. 34,35 Such platform should provide ultrathin membranes with close control on pore size over the range of small EVs. Another reason for minimal thickness is to improve tissue barrier function in a direct co-culture format by allowing physical contact and fast exchange of soluble factors, [36][37][38] establishing a more physiologically relevant model.…”

Nanopatterned Thermoresponsive Functionalization of Substrates via Nanosphere Lithography

“…This advantage may be of particular value to large area nanoporous membranes with precisely engineered pore properties that would otherwise be altered and compromised by a conformal polymer coating. 33,[35][36][37][38][39][40] Our aim is to provide a straightforward methodology for the indirect patterning of SAMs at the nanoscale.…”