Surface-functionalization of PDMS for potential micro-bioreactor and embryonic stem cell culture applications

This study presents a novel and inexpensive method to prepare a disposable micro-bioreactor for stem cell expansion. The micro-bioreactor was fabricated in the form of a fixed bed bioreactor with a microchannel reactor bed. The micro-bioreactor was constructed from polydimethylsiloxane (PDMS), and the microchannel was functionalized to enable cell adhesion and resistance to bovine serum albumin protein adsorption. The PDMS reactor bed surface was activated by oxygen plasma, then aminized with trimethoxysilylpropyl(polyethyleneimine), followed by grafting with carboxylmethyl cellulose (CMC) and gelatin in sequence. The functionalized PDMS surface demonstrated improved hydrophilicity and antifouling properties. The grafting of gelatin promoted cell adhesion. The functionalized surface was found to be biocompatible with MDA-MB-231 and Oct4b2 cells and was demonstrated to facilitate cell proliferation. The expanded Oct4b2 cells retained their proliferation potential, undifferentiated phenotype and pluripotency.