Polyfluorinated aromatics are essential to materials science as well as the pharmaceutical and agrochemical industries and yet are often difficult to access. This Communication describes a photocatalytic hydrodefluorination approach which begins with easily accessible perfluoroarenes and selectively reduces the C-F bonds. The method allows facile access to a number of partially fluorinated arenes and takes place with unprecedented catalytic activity using a safe and inexpensive amine as the reductant.

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A serine-based zwitterionic poly(serine methacrylate) (pSerMA) was developed in this work to be used as a potential antifouling material. A surface-initiated photoiniferter-mediated polymerization (SI-PIMP) method was used to graft polymer brushes on gold surfaces. The pSerMA-grafted samples with different polymer film thicknesses were readily prepared by varying the UV-irradiation time. With the optimal film thickness, the adsorptions from bovine serum albumin, human serum, and human plasma onto the pSerMA-grafted surfaces, as evaluated by a surface plasmon resonance (SPR) biosensor, were 1.8, 9.2, and 12.9 ng/cm(2), respectively, comparable to the traditional antifouling material such as poly(ethylene glycol). The pSerMA-grafted surfaces also strongly resisted adhesion from bovine aortic endothelial cells. This is the first work to develop an amino acid-based zwitterionic polymer as an antifouling material, demonstrating that pSerMA is a promising alternative to the traditional ethylene glycol-based antifouling materials.

In this work, polyacrylamide is investigated as an ultralow fouling surface coating to highly resist protein adsorption, cell adhesion, and bacterial attachment. Polyacrylamide was grafted on gold surfaces via surface-initiated atom transfer radical polymerization (ATRP). Protein adsorption from a wide range of biological media, including single protein solutions of fibrinogen, bovine serum albumin, and lysozyme, dilute and undiluted human blood serum, and dilute and undiluted human blood plasma, was studied by surface plasmon resonance (SPR). Dependence of the protein resistance on polyacrylamide film thickness was examined. With the optimal film thickness, the adsorption amount of all three single proteins on polyacrylamide-grafted surfaces was <3 pg/mm(2), close to the detection limit of SPR. The average nonspecific adsorptions from 10% plasma, 10% serum, 100% plasma, and 100% serum onto the polyacrylamide-grafted surfaces were 5, 6.5, 17, and 28 pg/mm(2), respectively, comparable (if not better) than the adsorption levels on poly(ethylene glycol) (PEG) and zwitterionic poly(sulfobetaine methacrylate) surfaces, the best antifouling materials known to date. The polyacrylamide-grafted surfaces were also shown strongly resistant to adhesion from bovine aortic endothelial cells and two bacterial species, Gram-positive Staphylococcus epidermidis ( S. epidermidis ) and Gram-negative Pseudomonas aeruginosa ( P. aeruginosa ). Strong hydrogen bond with water is considered the key attribute for the ultralow fouling properties of polyacrylamide. This is the first work to graft gold surfaces with polyacrylamide brushes via ATRP to achieve ultralow fouling surfaces, demonstrating that polyacrylamide is a promising alternative to traditional PEG-based antifouling materials.

This work highlights the role of photocatalyst volume in controlling photoquenching events and is exploited to control the reaction outcomes.