Nanoclay-reinforced alginate aerogels: preparation and properties.

Flame-retardant materials that are mechanically robust, low cost and non-toxic from green and renewable resources are highly demanded in many fields. In this work, aerogels of alginate extracted from seaweeds were fabricated and reinforced with nanoclay. The nanoclay particles increase the molecular ordering (crystallinity) of the aerogels through physical interactions with alginate molecules. They also served as cross-linkers and flame-retardant additives to improve the mechanical strength, elasticity, thermal stability and flame-retarding properties of the aerogels. Under exposure to a butane flame (750 °C), the aerogels maintained their structural integrity and did not produce drips. An optimal loading of nanoclay which led to the best flame retardancy (non-flammable) of the aerogel was determined. The results of this work demonstrate that alginate-nanoclay composite aerogels can be promisingly used as flame-retardant thermal insulation materials.

Preparation of PLGA microspheres loaded with niclosamide via microfluidic technology and their inhibition of Caco-2 cell activity in vitro.

Niclosamide (NIC) is a multifunctional drug that regulates various signaling pathways and biological processes. It is widely used for the treatment of cancer, viral infections, and metabolic disorders. However, its low water solubility limits its efficacy. In this study, poly(lactic-co-glycolic acid) (PLGA) and hyaluronic acid (HA), which exhibit good biocompatibility, biodegradability, and non-immunogenicity, were conjugated with niclosamide to prepare PLGA-HA-niclosamide polymeric nanoparticles (NIC@PLGA-HA) using microfluidic technology. The obtained microspheres had a uniform size distribution, with an average mean size of 442.0 ± 18.8 nm and zeta potential of -25.4 ± 0.41 mV, indicating their stable dispersion in water. The drug-loading efficiency was 8.70%. The drug-loaded microspheres showed sustained release behavior at pH 7.4 and 5.0, but not at pH 2.0, and the drug release kinetics were described by a quasi-first-order kinetic equation. The effect of the drug-loaded microspheres on the proliferation of Caco-2 cells was detected using the MTT assay. Hydrophilic HA-modified NIC@PLGA-HA microspheres prepared via microfluidic technology increased the cellular uptake by Caco-2 cells. Compared to the same concentration of NIC, the NIC@PLGA-HA microspheres demonstrated a stronger inhibitory effect on Caco-2 cells owing to the combined effect of PLGA, HA, and NIC. Therefore, the pH-responsive NIC@PLGA-HA microspheres synthesized using microfluid technology increased the solubility of NIC and improved its biological activity, thus contributing to the demand for intestinal drug carriers.

Synthesis, characterization and magnetic properties of hollow microspheres with micro-mesoporous shells assembled from cobalt-based ferrocenyl coordination polymers.

Hollow magnetic microspheres with micro-mesoporous shells were constructed with layered cobalt-based ferrocenyl coordination polymers (Co-Fc-HCPS) through a one-step Ostwald ripening process. The diameters of microspheres and corresponding cavities were controlled in the range of several microns by tuning the reaction time and reactant concentration, which would attribute the microspheres with high loading, and enhanced mass diffusion and transfer efficiency. The high crystallinity of hollow microspheres allowed determination of the crystal structure of cobalt-based ferrocenyl coordination polymer, which crystallized in Brucite-type layered structure with the formula of Co(4)(OH)(4)(FcDC)(2), (H(2)FcDC=1,1'-ferrocenedicarboxylic acid), by combination of powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), element analysis (EA), and Fourier transform infrared spectroscopy (FT-IR). N(2) adsorption/desorption investigation revealed the existence of both mesopores around 3.81 nm and micropores of ca. 1 nm in the shells. The hollow microspheres exhibited spin-canted antiferromagnetism with weak ferromagnetic ordering below ~52 K, which showed a remanent magnetization (Mr) of 1.0 µ(B) and a large coercive field (Hc) of 5 kOe at 7 K.

Synthesis of Fe3O4@poly(methylmethacrylate-co-divinylbenzene) magnetic porous microspheres and their application in the separation of phenol from aqueous solutions.

A simple strategy to fabricate magnetic porous microspheres of Fe(3)O(4)@poly(methylmethacrylate-co-divinylbenzene) was demonstrated. The magnetic microspheres, consisting of polymer-coated iron oxide nanoparticles, were synthesized by the modified suspension polymerization of methacrylate and divinylbenzene in the presence of a magnetic fluid. The morphology and the properties of the magnetic porous microspheres were examined by scanning electron microscopy, transmission electron microscopy, superconducting quantum interference device, Fourier transform infrared spectroscopy, thermogravimetry, and X-ray powder diffraction. The pore size distribution and the specific surface area of the microspheres were measured by nitrogen sorption and mercury porosimetry technique. As predicted from the previous knowledge, the magnetic porous microspheres possessed a high specific surface area using n-hexane as a porogen. It was further found that the amounts of divinylbenzene and methacrylate, the ratio of porogens, and the dosage of ferrofluids affect the specific surface area of the microspheres. Furthermore, the microspheres were applied to remove phenol from aqueous solutions. The results showed that the microspheres had a high adsorption capacity for phenol and a high separation efficiency due to their porous structure, polar groups, and superparamagnetic characteristic.

[Cloning and expression of the pig skeletal muscle musclin gene].

We found seven tag sequence with high homology in dbEST by using human musclin gene, and got its cDNA sequence, which consists of 651bp and the open reading frame was 54-452 bp detected by RT-PCR, encoding 132 amino acid residue protein. The new gene has high homology with that of human, mouse and rat, the rate is 87.2%, 77.6% and 77.9%, respectively; the gene fragment was cloned into expression vector pGEX-4T-1, and the recombinant was transformed into E. coli BL21. Induced by IPTG, the fusion protein GST-musclin, a 38.59 kD protein was successfully expressed in E. coli BL21 and identified by Western blotting.