Poly-2-methyl-2-oxazoline: a peptide-like polymer for protein-repellent surfaces.
Surface coatings with so-called protein-repellent or nonfouling polymers have become indispensable for the development of modern therapeutic and diagnostic medical devices such as biosensors, drug-delivery capsules, and biomedical implants. Nowadays, poly(ethylene glycol) (PEG) is routinely used for these purposes. However, there is increasing evidence that PEG has limited long-term stability, particularly in vivo. Here we investigate poly(2-methyl-2-oxazoline) (PMOXA) as a potential alternative polymer. We designed comb copolymers consisting of a polycationic poly(l-lysine) backbone and PMOXA side chains by analogy to precisely studied and highly protein-repellent PEG-based systems. Using optical waveguide lightmode spectroscopy, we quantitatively compare the in situ self-assembly of the comb copolymers on negatively charged surfaces and the exposure of the formed monolayers to full human serum. We find that the PMOXA-based coatings with an optimal side-chain grafting density eliminate protein adsorption to a level of <2 ng/cm2; that is, they quantitatively equal the protein-repellent properties of the best PEG-based coatings.
Konradi
Rupert
R
Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zurich, Switzerland. rupert.konradi@mat.ethz.ch
Pidhatika
Bidhari
B
Mühlebach
Andreas
A
Textor
Marcus
M
D000327:Adsorption; D001798:Blood Proteins / Q000737:chemistry; D002686:Chitin / Q000031:analogs & derivatives* / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D011073:Polyamines; D011092:Polyethylene Glycols / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry; D013499:Surface Properties
D001798:Blood Proteins; D020099:Coated Materials, Biocompatible; D011073:Polyamines; C117403:poly(2-methyl-2-oxazoline); D002686:Chitin; D011107:Polylysine; D011092:Polyethylene Glycols