We synthesized a zwitterionic dopamine derivative (ZW-DOPA) containing both catechol and amine groups, and we demonstrated an excellent marine antifouling surface by controlling the oxidation of ZW-DOPA. The oxidation was mediated by the deprotonation of catechol or the addition of an oxidant (ammonium persulfate (AP) or sodium periodate (NaIO4)). The oxidation and subsequent molecular transformation of ZW-DOPA was investigated over time by UV–vis spectroscopy. Among the different oxidation conditions tested, NaIO4-induced ZW-DOPA coating was the most efficient and successfully formed on various substrates, such as titanium dioxide, stainless steel, and nylon. Compared with uncoated substrates, ZW-DOPA-coated substrates showed high resistance to marine diatom adhesion. Considering the ease of use and substrate independence of the ZW-DOPA coating, this method shows promise as a basis for inhibiting marine fouling on a variety of substrates used in the marine industry and aquatic environments.

Numerous coating strategies are available to control the surface properties and confer new properties to substrates for applications in energy, environment, biosystems, etc., but most have the intrinsic limitations in the practical setting: (1) highly specific interactions between coating materials and target surfaces are required for stable and durable coating; (2) the coating of bulk substrates, such as fruits, is time-consuming or is not achievable in the conventional solution-based coating. In this respect, material-independent and rapid coating strategies are highly demanded. We demonstrate spray-assisted nanocoating of supramolecular metal-organic complexes of tannic acid and ferric ions. The spray coating developed is material-independent and extremely rapid (<5 sec), allowing for coating of commodity goods, such as shoe insoles and fruits, in the controlled fashion. For example, the spray-coated mandarin oranges and strawberries show significantly prolonged post-harvest shelf-life, suggesting practical potential in edible coating of perishable produce.

HIGHLIGHTS • Controllable and large-scale practical growth of plasmonic Ag-decorated vertically aligned 2D MoS 2 nanosheets on graphene. • Realization of the synergistic effects of surface plasmon resonance and favorable graphene/MoS 2 heterojunction to enhance the photoelectrochemical reactivity of 2D MoS 2. ABSTRACT A controllable approach that combines surface plasmon resonance and twodimensional (2D) graphene/MoS 2 heterojunction has not been implemented despite its potential for efficient photoelectrochemical (PEC) water splitting. In this study, plasmonic Ag-decorated 2D MoS 2 nanosheets were vertically grown on graphene substrates in a practical large-scale manner through metalorganic chemical vapor deposition of MoS 2 and thermal evaporation of Ag. The plasmonic Ag-decorated MoS 2 nanosheets on graphene yielded up to 10 times higher photo-to-dark current ratio than MoS 2 nanosheets on indium tin oxide. The significantly enhanced PEC activity could be attributed to the synergetic effects of SPR and favorable graphene/2D MoS 2 heterojunction. Plasmonic Ag nanoparticles not only increased visible-light and near-infrared absorption of 2D MoS 2 , but also induced highly amplified local electric field intensity in 2D MoS 2. In addition, the vertically aligned 2D MoS 2 on graphene acted as a desirable heterostructure for efficient separation and transportation of photo-generated carriers. This study provides a promising path for exploiting the full potential of 2D MoS 2 for practical large-scale and efficient PEC water-splitting applications.

The posttranslational modification of neural cell-adhesion molecule (NCAM) with polysialic acid (PSA) and the spatiotemporal distribution of PSA-NCAM play an important role in the neuronal development. In this work, we developed a tissue-based strategy for metabolically incorporating an unnatural monosaccharide, peracetylated N-azidoacetyl-D-mannosamine, in the sialic acid biochemical pathway to present N-azidoacetyl sialic acid to PSA-NCAM. Although significant neurotoxicity was observed in the conventional metabolic labeling that used the dissociated neuron cells, neurotoxicity disappeared in this modified strategy, allowing for investigation of the temporal and spatial distributions of PSA in the primary hippocampal neurons. PSA-NCAM was synthesized and recycled continuously during neuronal development, and the two-color labeling showed that newly synthesized PSANCAMs were transported and inserted mainly to the growing neurites and not significantly to the cell body. This report suggests a reliable and cytocompatible method for in vitro analysis of glycans complementary to the conventional cell-based metabolic labeling for chemical glycobiology.