Poor water solubility and low bioavailability of hydrophobic flavonoids such as rutin remain as substantial challenges to their oral delivery via functional foods. In this study, the effect of pH and the addition of a protein (sodium caseinate; NaCas) on the aqueous solubility and stability of rutin was studied, from which an efficient delivery system for the incorporation of rutin into functional food products was developed. The aqueous solubility, chemical stability, crystallinity, and morphology of rutin (0.1–5% w/v) under various pH (1–11) and protein concentrations (0.2–8% w/v) were studied. To manufacture the concentrated colloidally stable rutin–NaCas particles, rutin was dissolved and deprotonated in a NaCas solution at alkaline pH before its subsequent neutralisation at pH 7. The excess water was removed using ultrafiltration to improve the loading capacity. Rutin showed the highest solubility at pH 11, while the addition of NaCas resulted in the improvement of both solubility and chemical stability. Critically, to achieve particles with colloidal stability, the NaCas:rutin ratio (w/w) had to be greater than 2.5 and 40 respectively for the lowest (0.2% w/v) and highest (4 to 8% w/v) concentrations of NaCas. The rutin–NaCas particles in the concentrated formulations were physically stable, with a size in the range of 185 to 230 nm and zeta potential of −36.8 to −38.1 mV, depending on the NaCas:rutin ratio. Encapsulation efficiency and loading capacity of rutin in different systems were 76% to 83% and 2% to 22%, respectively. The concentrated formulation containing 5% w/v NaCas and 2% w/v rutin was chosen as the most efficient delivery system due to the ideal protein:flavonoid ratio (2.5:1), which resulted in the highest loading capacity (22%). Taken together, the findings show that the delivery system developed in this study can be a promising method for the incorporation of a high concentration of hydrophobic flavonoids such as rutin into functional foods. 相似文献
Consolidation of the results of structural, spectroscopic and kinetic studies of a range of intrazeolite guests and their reactions have led to the development of the “crown ether-zeolite ligand analogy” and the concept of the “zeolate” as a macrospheroidal or macrocylindrical multidentate anionic ligand. This view of a zeolite cavity or channel as a collection of interconnected aluminosilicate crown ether-like building blocks, permits a coordination chemistry approach to the understanding of metal-ligand bonding (capping, anchoring, complexing, stabilizing and structure-directing phenomena) in a variety of zeolite guest-host inclusion systems. In this paper we focus attention on the role that the zeolate ligand plays in the organization of semiconductor precursors and their assembly to semiconductor nanoclusters with particular reference to II-VI nanomaterials. 相似文献
The X-ray structure of H2T(3-Py)P·HgI2·C60, cocrystallized from a chlorobenzene/methanol solvent mixture containing 5,10,15,20- tetra(3-pyridyl)porphyrin, HgI2 and C60, has been determined. A new two dimensional arrangement of the tetra(3-pyridyl)porphyrin molecules joined by coordination to HgI2 is formed. These assemblies are connected by close C60-porphyrin π–π interactions leading to the alignment of the porphyrins into linear alternating fullerene porphyrin columns. The structure is compact with no significant cavities. 相似文献
Quiescent hydrothermal conditions were applied to synthesis of the sandwich nanocomposites of reduced graphite oxide (rGO) and periodic mesoporous silica (PMS) with vertically aligned mesochannels. It was found that the formation of the PMS–rGO–PMS sandwich structure is very sensitive to the surface and synthesis conditions. Although a higher temperature hydrothermal condition promotes reduction of GO and formation of bulky mesoporous nanoparticles, quiescent hydrothermal condition can serve as an alternative approach to obtain the unusual nanocomposites and slightly promote the structural stability of PMS on the surface of rGO. 相似文献
Magninos (neutral spin 1/2 fermions with mass 4–10 GeV and anomalous magnetic moment μ≈10−2) have been proposed as a solution to both the solar neutrino and dark matter problems. Direct detection of galactic halo magninos is possible via their coherent interaction with heavy nuclei. In this paper we have calculated the relevant non-relativistic cross section. We find a typical counting rate of about 100 events per day per kilogram of either a silicon or germanium detector. The magnetic moment of the magnino was needed in order to solve the solar neutrino problem. When scattering off of heavy nuclei, the charge radius r of the magnino is also relevant. 相似文献
Flammability studies are conducted to evaluate the behavior of materials exposed to fire. In this study, microscale combustion calorimetry (MCC) and cone calorimetry methods were applied to acquire the flammability characteristics of red and grey extruded polystyrene (XPS) samples. To understand the effect of changes between parameters, Pearson’s correlation coefficient was used to examine their linear relationships. From the research, moderate and weak correlations were recorded between the total heat release rates from both methods for red and grey XPS, respectively. Plotting peak heat release rate against heat release temperature for MCC and ignition temperature for cone test showed that 25, 35 and 50 kW m?2 incident heat fluxes of the cone test fall within 0.2 K s?1 and 0.5 K s?1 heating rates of MCC. Also, all the MCC parameters except char yield and total heat release presented good correlations with the cone calorimetry flammability characteristics. Hence, MCC could be used in conjunction with cone calorimetry to accurately and reliably assess the flammability of materials.
The lead–acid battery recycling industry is very well established, but the conventional pyrometallurgical processes are far from environmentally benign. Hence, recent developments of lead–acid battery recycling technologies have focused on low-temperature (electro)hydrometallurgical processes, the subject of this review, covering modified electrolytes, improved reaction engineering, better reactor design and control of operating conditions. 相似文献