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Micrometer-scale monodisperse droplets are produced to generate nanowalled supramolecular microcapsules using microfluidics for high reproducibility and high-throughput manipulation, efficient material consumption, and control over hierarchical structure, shape, and size. In this study, an optimized microfluidic droplet generation technique and a unique liquid–liquid interfacial polymerization method were applied to fabricate the monodisperse polyrotaxane–based supramolecular microcapsules in a fast and simple way. To minimize the uncertainty due to droplet volume variation, the inlet pressures were supplied from the same source while lowering the interfacial tension and the main channel hydrodynamic resistance, which are critical for high monodispersity. The target polyrotaxane network (PN) was simply formed at the interface of the water and oil phases in ultra-monodisperse microdroplets via the cucurbit[6]uril (CB6)-catalyzed azide–alkyne cycloaddition (CB6-AAC) reaction between azido- and alkyne-functionalized tetraphenylporphyrin monomers (TPP-4AZ and TPP-4AL). The thickness of the interfacially assembled PN microcapsules was 20 nm as analyzed by cross-sectional TEM and TEM-EDX techniques. The resultant water-in-oil PN microcapsules were highly monodisperse in size and able to retain target molecules. Here, rhodamine 6G (Rh6G)-loaded PN microcapsules were fabricated, and the release rate of the Rh6G cargo was investigated over time for controlled drug release applications.

In this study, sulfur-enriched microporous organic polymer (MOP) was prepared using one-pot Shiff-base type polycondensation reaction of thiophendicarboxaldehyde with melamine. With 195.731 m2 g−1 surface area and 0.047 cm3 g−1 pore volume, the as-synthesized MOP has a cotton-like morphology and a micropore-dominated pore size distribution. After loading MOP with nickel as a co-catalyst, we demonstrated that the obtained framework could be used as an efficient and robust electrocatalyst for hydrogen evolution reaction (HER) in an alkaline medium with the optimum composite (Ni2@MOP) exhibiting a low onset potential of −66 mV. Furthermore, the optimum electrocatalyst showed good stability, delivering 91% faradaic efficiency (FE) after a 3.5 h chronoamperometry experiment.

We report here the synthesis and characterization of a water dispersible conjugated polymer nanoparticle-based photosensitizer and its application in the antibacterial and anticancer phototherapies. Nanoparticles (CPPN) were synthesized in one-pot by nanoprecipitation method, in which a hydrophobic azide functionalized, red-emitting thiophene-benzothiodiazole based conjugated polymer (CP-AZ) was cross-linked with a hydrophilic, propargylamine functionalized porphyrin (TPP-4AL) through cucurbit[6]uril (CB6) catalyzed azide-alkyne cycloaddition (CB6-AAC) reaction. CPPN demonstrated high stability in aqueous medium for more than a month without any visible aggregation and appeared to be a good photosensitizer with high light-triggered reactive oxygen species (ROS) generation ability. Consequently, CPPN displayed photo-induced biocidal activity against Gram-negative (Escherichia coli, E. coli) and Gram-positive (Bacillus subtilis, B. subtilis and Staphylococcus aureus, S. aureus) bacteria. When bacteria suspension was incubated with CPPN (20 μg ml−1) and irradiated with white light (22 mW cm−2) for 10 min, more than 3.5-log reduction in colony-forming units (CFUs) was recorded for the three model bacteria. CPPN demonstrated minimal dark cytotoxicity against the bacteria. Moreover, the cytotoxicity of CPPN on mammalian cell was studied using MCF-7 breast cancer cell line. The results demonstrated that CPPN is non-toxic to mammalian cells in the dark even at a high concentration of 112.5 μg ml−1 and this feature makes CPPN an ideal photosensitizer.

Herein, we report the synthesis of a new supramolecular polymeric network (PCN) assembled through cross linking of propyl bromide substituted tetraphenyl porphyrin with perhydroxy-cucurbit [8]uril and its use in the electrocatalytic hydrogen evaluation reaction after loading with nickel and integrating with in situ -electrochemically reduced graphene oxide (ERGO). Electrode was prepared by first coating graphene oxide on the FTO substrate followed by layering the nickel loaded PCN and finally by applying an appropriate voltage to reduce the graphene oxide in situ electrochemical reaction. The loading of nickel cocatalyst into PCN together with the integration of ERGO layer substantially improved its HER efficiency. Effect of various concentrations of Ni and GO on the HER activity of the developed electrocatalyst were investigated. Therein, ERGO(1)/Ni-2@PCN catalyst containing 41% Ni and 50% GO (with respect to PCN) with only one layer of each component demonstrated excellent HER activity and stability with low onset and overpotentials of -20 mV, eta@10 mA cm(-2) of -360 mV, respectively, and remarkable hydrogen generation rate of 27.5 mmol h(-1) g(-1) in 1 M KOH. This noble-metal-free catalytic system is simple yet highly promising for the efficient hydrogen evolution reaction from water splitting.