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In this article, we presented a general protocol to prepare biomolecule-immobilized mussel-inspired polydopamine (PDA) coatings to improve the blood compatibility of broad ranges of material surfaces. It needs only a simple immersion of substrates in dopamine solution at alkaline pH to form mussel-inspired PDA coating, and then immersing the PDA coated substrates into biomolecule solution to conjugate biomolecules. XPS, water contact angle analysis, and protein assay confirmed that biomolecules could be successfully coated on several material surfaces, including nylon, cellulose, and polyethersulfone membrane surfaces. For the protein fouling resistance, the bovine serum albumin (BSA) modified surfaces were more effective than the amino acid modified surfaces. And the platelet adhesion on the BSA-modified material surfaces was obviously depressed. These results indicated that the blood compatibility of the surfaces was improved by the biomacromolecule-immobilized mussel-inspired coating which might be considered as a universal coating to modify a wide variety of materials.

To address the debates on whether superhydrophobic coatings can reduce fluid drag for underwater motions, we have achieved an underwater drag-reducing effect of large superhydrophobic submarine models with a feature size of 3.5 cm × 3.7 cm × 33.0 cm through sailing experiments of submarine models, modified with and without superhydrophobic surface under similar power supply and experimental conditions. The drag reduction rate reached as high as 15%. The fabrication of superhydrophobic coatings on a large area of submarine model surfaces was realized by immobilizing hydrophobic copper particles onto a precross-linked polydimethylsiloxane (PDMS) surface. The pre-cross-linking time was optimized at 20 min to obtain good superhydrophobicity for the underwater drag reduction effect by investigating the effect of pre-cross-linking on surface wettability and water adhesive property. We do believe that superhydrophobic coatings may provide a promising application in the field of drag-reducing of vehicle motions on or under the water surface.

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Different metalloporphyrin model compounds have been synthesized to study the mechanisms of cytochrome P450s with various terminal oxidants, and numerous intermediates have been reported. However, the detailed mechanism of the oxygen atom transfer from iodosylarene to the substrates remains unclear. Here we report the direct ultraviolet-visible spectroscopic observation of the soluble iodosylarene-manganese porphyrin adduct following catalytic oxidation using 2,4,6-tri-tert-butylphenol as the reductant. When the reductant is changed to cisstilbene, the rate-determining step also changes. Both the iodosylarene-manganese porphyrin adduct and [(porphyrin)Mn(V) ¼ O] species may be simultaneously observed. In the absence of reductant, the adduct of iodosylarene with sterically hindered [Mn(meso-tetrakis(2,6-dichlorophenyl)porphinato)Cl] is immediately formed, and smoothly converted into a highvalent [(porpyrinato)Mn ¼ O]. Electrospray ionization mass spectrometry analysis of the reaction further confirms the transformation between these species. This study provides an insight into the mechanism of oxygen transfer within the haem-containing enzymatic systems.

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