Mcelroymcleod9711

Collagen (COL) and bacterial cellulose (BC) were chemically recombined by Malaprade and Schiff-base reactions. A three-dimensional (3D) porous microsphere of COL/BC/Bone morphogenetic protein 2 (BMP-2) with multistage structure and components were prepared by the template method combined with reverse-phase suspension regeneration. The microspheres were full of pores and had a rough surface. The particle size ranged from 8 to 12 microns, the specific surface area (SBET) was 123.4 m2/g, the pore volume (VPore) was 0.59 cm3/g, and the average pore diameter (DBJH) was 198.5 nm. The adsorption isotherm of the microspheres on the N2 molecule belongs to that of mesoporous materials. The microspheres showed good biocompatibility, and the 3D porous microspheres with multiple structures and components effectively promoted the adhesion, proliferation, and osteogenic differentiation of mice MC3T3-E1 cells. The study can provide a theoretical basis for the application of COL/BC porous microspheres in the field of bone tissue engineering. A platform of enzymatically-crosslinked Collagen/Tyramine hyaluronan derivative (Col/HA-Tyr) hydrogels with tunable compositions and gelation conditions was developed to evaluate the impact of the preparation conditions on their physical, chemical and biological properties. At low HA-Tyr content, hydrogels exhibited a fibrillar structure, with lower mechanical properties compared to pure Col hydrogels. At high HA-Tyr and Horse Radish Peroxydase (HRP) content, a microfibrillar network was formed beside the banded Col fibrils and a synergistic effect of the hybrid structure on mechanical properties was observed. These hydrogels were highly resistant against enzymatic degradation while keeping a high degree of hydration. Unlike HA-Tyr hydrogels, encapsulation of human dermal fibroblasts within Col/HA-Tyr hydrogels allowed for high cell viability. These results showed that high HA-Tyr and HRP concentrations are required to positively impact the physical properties of hydrogels while preserving collagen fibrils. Those Col/HA-Tyr hydrogels appear promising for novel tissue engineering applications following a biomimetic approach. Fucoidan/trimethylchitosan nanoparticles (FUC-TMC-NPs) have the potential to improve the immunostimulating efficiency of anthrax vaccine adsorbed (AVA). FUC-TMC-NPs with positive (+) or negative (-) surface charges were prepared via polyelectrolyte complexation, both charged NP types permitted high viability and presented no cytotoxicity on L929, A549 and JAWS II dendritic cells. Flow cytometry measurements indicated lower (+)-FUC-TMC-NPs internalization levels than (-)-FUC-TMC-NPs, yet produced high levels of pro-inflammatory cytokines IFN-γ, IL12p40, and IL-4. Moreover, fluorescence microscope images proved that both charged NP could deliver drugs into the nucleus. In vivo studies on A/J mice showed that (+)-FUC-TMC-NPs carrying AVA triggered an efficient response with a higher IgG anti-PA antibody titer than AVA with CpG oligodeoxynucleotides, and yielded 100 % protection when challenged with the anthracis spores. Furthermore, PA-specific IgG1 and IgG2a analysis confirmed that (+)-FUC-TMC-NPs strongly stimulated humoral immunity. In conclusion, (+)-FUC-TMC-NP is promising anthrax vaccine adjuvant as an alternative to CpG. The hydration of calcium aluminate cement (CAC) in the presence of sodium alginate which is known to slightly retard Portland cement, was studied using heat flow calorimetry and mortar strength testing. Most surprisingly, addition of alginate resulted in an earlier occurrence of the maximal heat release as well as an increased early strength, thus confirming that in CAC alginate acts as accelerator. The thickening effect of alginate was effectively compensated using a superplasticizer while retaining its accelerating property. An investigation of the pore solution composition indicated that in the presence of alginate the concentration of calcium ions was reduced. Such effect normally causes retardation of cement hydration and should delay the formation of C-A-H phases. Apparently, the strong calcium ion complexing ability of alginate promotes the formation of C-A-H via e.g. a templating effect. A combined application of alginates and lithium salts presents a viable option to reduce the lithium consumption in CAC acceleration. A simple and universal strategy was developed to prepare cellulose/dye composite film, as colorimetric sensor for heavy metal ions (HMIs) detection. After regenerating cellulose solution in ethanol, the regenerated films were further soaking in dye/ethanol solution followed by hot-pressing, to obtain cellulose/dye composite films. 1-(2-pyridylazo)-2-naphthol (PAN) was used as an example, and the resultant cellulose/PAN composite films (CPs) possessed robust mechanical property (tensile strength of 52.9 MPa), light transmittance, and thermodynamic stability. PAN distributed uniformly as nanoparticles of 30 nm on cellulose because of the interaction between N of azo group of PAN and cellulose. find more When used as colorimetric sensor for Zn2+ detection, the detection limit of CP was as low as 100 ppb, and the color change was distinguishable after testing with tap water. Moreover, two more dyes including 1-(2-thiazolylazo)-2-naphthol (TAN) and dithizone (Dith) were also immobilized successfully on cellulose, and the resultant films were effective colorimetric sensor for HMIs like Zn2+ and Cu2+. This work provided a facile and universal method to prepare cellulose-based colorimetric sensor or HMI detection, demonstrating great potential in water treatment and natural resources utilization. Diclofenac sodium (DS) is an emergent pollutant, and among the methods investigated for its removal, adsorption is the most widely utilized technique. Hydroxyapatite and chitosan are biomaterials often used for adsorption. However, both biomaterials are limited due to their low chemical stability in an acidic medium; furthermore, pure hydroxyapatite interacts poorly with diclofenac. In this work, hydroxyapatite was organofunctionalized with 3-aminopropyltrimethoxysilane and further used to obtain amino hydroxyapatite /chitosan hybrids by crosslinking with glutaraldehyde at pH 3, 4, 5, and 6. X-ray diffraction patterns indicated the preservation of the hydroxyapatite phase under all pH conditions. Based on the control reaction of the amino hydroxyapatite with glutaraldehyde and its further reduction in sodium borohydride, the formation of CN moieties was highlighted as the main interaction mechanism between the aldehyde and amino groups. Therefore, crosslinking with glutaraldehyde was evaluated by infrared, Raman spectroscopy, and 13C NMR techniques; the results suggested contributions of imine formation and hydrogen bonding.