Editors: | F. Kongoli, F. Marquis, P. Chen, T. Prikhna, N. Chikhradze |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2018 |
Pages: | 392 pages |
ISBN: | 978-1-987820-92-8 |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
Whereas biorepulsive oligo- and poly(ethylene glycols) (OEGs and PEGs) are widely used for different applications, they have not been utilized yet as materials for free-standing nanomembranes. In this context, I discuss fabrication and potential applications of novel PEG hydrogel films and membranes, abbreviated as PHFs and PHMs, respectively. They were prepared by thermally activated crosslinking of amine- and epoxy-terminated, star-branched PEG oligomers, and characterized by tunable thicknesses of 4-300 nm [1]. These systems possess a variety of useful properties, including biocompatibility, robustness, and extreme elasticity [1,2]. They can serve as a basis for hybrid materials, advanced nanofabrication, and lithography, using electron irradiation and ultraviolet light as writing tools [1-3]. They can also be used as highly sensitive elements in MEMS as well as in humidity sensors and moisture-responsive nanoelectronic devices, relying on optical or resistive transduction technique. In particular, their resistance changes by ca. 5.5 orders of the magnitude upon relative humidity variation from 0 to 100%, which is an unprecedented response for homogeneous materials [4]. The PHFs and PHMs are also able to host protein-specific receptors, providing, at the same time, protein-repelling and humidity-responsive matrix with a characteristic mesh size up to 8.4 nm [5]. A noticeable grafting density of the test avidin protein, specifically attached to the biotin moieties, coupled to the free amine groups in the PHMs, was achieved, whereas non-specific protein adsorption was efficiently suppressed. The engineering of PHMs with biomolecule-specific receptors and their loading with biomolecules are of potential interest for sensor fabrication and biomedical applications, including tissue engineering and regenerative therapy.