Cellulose Nanocrystal-ZnO Nanohybrids for Controlling Photocatalytic Activity and UV Protection in Cosmetic Formulation.

A high-performance semiconductor zinc oxide (ZnO) on melamine formaldehyde-coated cellulose nanocrystals (MFCNCs) was synthesized and evaluated for its application in smart cosmetics. These ZnO@MFCNC hybrid nanostructures were evaluated for their in vitro sun protection factor performance and photocatalytic activity under simulated UV and solar radiation. The photodegradation kinetics of a model pigment (methylene blue) was fitted to the Langmuir-Hinshelwood model.

Amphiphilic Cellulose Nanocrystals for Enhanced Pickering Emulsion Stabilization.

Sulfated cellulose nanocrystals (CNC) with high surface charge density are inadequate for stabilizing oil-water emulsions, which limits their applications as interfacial stabilizers. We performed end-group modification by introducing hydrophobic chains (polystyrene) to CNC. Results showed that the modified CNC are more effective in emulsifying toluene and hexadecane than pristine CNC.

Multilayer Assembly of Tannic Acid and an Amphiphilic Copolymer Poloxamer 188 on Planar Substrates toward Multifunctional Surfaces with Discrete Microdome-Shaped Features.

Tannic acid (TA) is a natural polyphenol compound with a broad spectrum of biological activities, the most notable of which being antioxidation. Poloxamer 188 (P188), a synthetic triblock copolymer of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), is amphiphilic in nature and best known for its ability to seal structurally damaged cellular membranes. The integration of both substances onto planar substrates could bring a new option for multifunctional coatings that are advantageous for implantable biomedical devices.

Water-based synthesis of cationic hydrogel particles: effect of the reaction parameters and in vitro cytotoxicity study.

Micro/nanoscale hydrogel particles are of great interest for biomedical applications, such as carriers for therapeutic delivery. Compared to conventional hydrogel particles that are mainly composed of vinylic monomers, we have introduced a simple methodology to prepare multi-functional cationic hydrogel particles by adopting the epoxy-amine chemistry in water exemplifying "click" characteristics. Herein, we investigate the effects of key reaction parameters, including time, temperature, reactant concentration and amine-epoxy stoichiometric ratio, on the preparation and properties of such hydrogel particles.

Ultrathin alternating copolymer nanotubes with readily tunable surface functionalities.

Well-defined ultrathin nanotubes (30 nm in diameter and of micrometer-scale length) were generated through the self-assembly of a novel alternative copolymer synthesized using an epoxy-thiol click-chemistry reaction. The self-assembly mechanism was investigated both by experiments and using dissipative particle dynamics (DPD) simulations. The obtained nanotubes can be readily functionalized with carboxy groups, amino groups, peptides, or other groups by simple modular click copolymerization.

Enhanced colloidal stability and antibacterial performance of silver nanoparticles/cellulose nanocrystal hybrids.

The aggregation of nanoparticles has been shown to significantly reduce the activity of nanomaterials, resulting in inferior performance. As an alternative to the use of traditional capping agents, stabilization of unstable nanoparticles with water-dispersible and biocompatible carriers is a promising strategy. A bioinspired coating strategy was developed and the hybrid nanoparticles displayed excellent colloidal stability that significantly improved antibacterial activity when silver nanoparticles (AgNPs) were used as a model.

Fluorinated raspberry-like polymer particles for superamphiphobic coatings.

Raspberry-like (RB) polymer particles were prepared, fluorinated, and cast onto glass plates to yield highly water- and oil-repellant superamphiphobic particulate coatings. To procure the RB particles, glycidyl-bearing 212 and 332 nm particles (abbreviated as s-GMA and l-GMA, respectively) were first prepared via surfactant-free free radical emulsion polymerization. Reacting the glycidyl groups of the l-GMA particles with 2,2'-(ethylenedioxy)bis(ethylamine) (EDEA) produced large amine-functionalized particles (l-NH2).

Facile aqueous-phase synthesis of multi-responsive nanogels based on polyetheramines and bisepoxide.

A new strategy for the preparation of nanogels from commercially available monomers of bisepoxide and aliphatic polyetheramine has been developed. The nanogels are generated in a one-pot process through aggregation polymerization of an in situ formed thermal sensitive intermediate polymer in an additive-free and catalyst-free aqueous environment. Such a facile process allows easy size tuning of the gel particles from the nanometer to the micron scale, simply by adjusting the reactant concentration.

Facile preparation of novel peptosomes through complex self-assembly of hyperbranched polyester and polypeptide.

This work reported for the first time a facile template-free method to prepare polypeptide-based vesicles (peptosomes) through one-step complex self-assembly of carboxyl-terminated hyperbranched polyester and cationic poly-l-lysine (PLL). The preparation of such peptosomes, named complex peptosomes (CPs) here, is very simple just by mixing two kinds of polymer aqueous solutions together. The CP size can be readily controlled from nanosize to microsize through the adjustment of polymer concentration.