Development of Porous and Flexible PTMC Membranes for In Vitro Organ Models Fabricated by Evaporation-Induced Phase Separation

Abstract

Polymeric membranes are widely applied in biomedical applications, including in vitro organ models. In such models, they are mostly used as supports on which cells are cultured to create functional tissue units of the desired organ. To this end, the membrane properties, e.g., morphology and porosity, should match the tissue properties. Organ models of dynamic (barrier) tissues, e.g., lung, require flexible, elastic and porous membranes. Thus, membranes based on poly (dimethyl siloxane) (PDMS) are often applied, which are flexible and elastic. However, PDMS has low cell adhesive properties and displays small molecule ad- and absorption. Furthermore, the introduction of porosity in these membranes requires elaborate methods. In this work, we aim to develop porous membranes for organ models based on poly(trimethylene carbonate) (PTMC): a flexible polymer with good cell adhesive properties which has been used for tissue engineering scaffolds, but not in in vitro organ models. For developing these membranes, we applied evaporation-induced phase separation (EIPS), a new method in this field based on solvent evaporation initiating phase separation, followed by membrane photo-crosslinking. We optimised various processing variables for obtaining form-stable PTMC membranes with average pore sizes between 5 to 8 µm and water permeance in the microfiltration range (17,000–41,000 L/m2/h/bar). Importantly, the membranes are flexible and are suitable for implementation in in vitro organ models.

Development of an In Vitro Airway Epithelial–Endothelial Cell Culture Model on a Flexible Porous Poly(Trimethylene Carbonate) Membrane Based on Calu-3 Airway Epithelial Cells and Lung Microvascular Endothelial Cells

“…Adhesion of Calu-3 cells on PTMC M0, M1, and M3 membranes was assessed by staining their nuclei ( Figure 1 ). The PTMC membranes had diverse properties, as described in a previous paper [ 23 ], most notably concerning their porosity and water transport. Briefly, M0 membranes were non-porous and non-permeable.…”

“…The synthesis of PTMC and fabrication of the membranes was described in detail previously [ 23 ]. Therefore, here we describe those only briefly.…”

“…PET membranes of cell culture inserts were removed. The PTMC membrane samples were then secured to the underside of the inserts (substrate side [ 23 ] facing up) using poly(ether ether ketone) (PEEK) membrane rings ( Figure S1 in Supplementary Material ), provided by Ronald C. van Gaal (Department of Biomedical Engineering, Biomedical Materials and Biochemistry, Eindhoven University of Technology, Eindhoven, The Netherlands). Plate rings ( Figure S1 ), also provided by Ronald C. van Gaal, were placed on top of wells of Falcon 12-well companion plates to elevate the inserts to allow cell culture medium to reach the underside of the inserts.…”

“…Moreover, PTMC-based films and scaffolds with suitable mechanical properties for cyclic stretch have been fabricated [ 20 , 22 ]. Here, we used PTMC membranes with various porosities, pore sizes, and water transport properties, which were developed earlier [ 23 ]. The PTMC membranes were either coated with levodopa (L-DOPA), a mixture of fibronectin, collagen I, and bovine serum albumin (FN/Col I/BSA) or L-DOPA followed by FN/Col I/BSA.…”

PLGA Multiplex Membrane Platform for Disease Modelling and Testing of Therapeutic Compounds

“…This challenging aspect is satisfied by the use of in vitro tools based on a membrane technology approach, which has been widely demonstrated to act as proper platform to model physiological and pathological conditions [5][6][7][8][9]. Indeed, these systems, besides portioning cells, offer them a well-controlled surrounding, taking advantage of the presence of a membrane that has been specifically tailored to better accomplish optimal tissue reconstruction [10][11][12][13]. Within the in vitro platform, polymeric membranes not only offer physical support but also drive cell adhesion and cellular contacts formation, thus acting as a biomimetic interface like an extracellular matrix.…”