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BACKGROUND: Bioglass has high brittleness and poor mechanical strength, which limits its application in bone defect of bearing part. Nitrogen oxide glass has higher strength and hardness. Therefore, nitriding treatment is expected to improve the mechanical strength of bioglass. OBJECTIVE: To analyze the effects of nitridation on the porosity, compressive strength, bending strength, degradation performance and mineralization activity of porous bioglass scaffolds. METHODS: This experiment was based on silicate glass (SiO2-CaO-P2O5-Na2O-ZnO), and nitriding it (SiO2 was replaced by 0%, 2%, 4%, 6% Si3N4, respectively). The basic glass (SiO2-CaO-P2O5-Na2O-ZnO-Si3N4) was prepared by melting method. The polyurethane foam was used as template and organic foam impregnation method was used to prepare porous bioglass scaffolds. The porosity, compressive strength, bending strength, and degradation performance in vitro of the porous bioglass scaffolds were measured in four groups. Four groups of scaffolds were immersed in simulated body fluid for 7 days. The surface morphology of the scaffold was observed with the scanning electron microscope. RESULTS AND CONCLUSION: (1) The porosity of the four groups had no statistical difference (P > 0.05). (2) With increased Si3N4 content, compressive strength and bending strength of porus bioglass scaffold increased, and there was statistical difference between each group (P < 0.05). (3) With increased Si3N4 content, the degradation performance of porous bioglass scaffolds decreased gradually in vitro. (4) Scanning electron microscope revealed that typical hydroxyapatite membrane was formed on the surface of porous bioglass scaffold without nitriding treatment and porous bioglass scaffold containing 2% Si3N4, but no hydroxyapatite membrane was formed in the other two groups. (5) Nitriding treatment can significantly enhance the mechanical strength of bioglass, but can reduce its degradation performance and mineralization activity in vitro.
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The development of human society is mainly marked by materials. “Academic Leadership Series, National Science Think Tank, Development Strategies of Chinese Disciplines in the Next 10 Years: Material Science” points out that: Material science has become the essential link for the development and deepening of modern science and technology, and plays a basic and leading role in the development of science and technology; The emergence of a new type of material can also drive the birth of an industry. The excessive consumption of resources and energy by process industry and the pollution of environment have become bottlenecks restricting the sustainable development of human society. Chemical engineering has always been important to achieve efficient transformation of materials and effective utilization of energy. In the 21st century, the objectives of chemical engineering have been transformed into: Relying on superior performance, friendly environment, and fully function, new structural and functional materials with good and complete functions to develop new process industrial technology and form new process flow and integration technology in order to achieve the goal of high efficiency, low consumption, and pollution-free. Membrane technology, with advanced separation materials as carriers, can achieve separation of substances and molecules at mild and low cost conditions. It is especially suitable for the needs of modern industry for energy saving, recycling of low-grade raw materials, and eliminating environmental pollution. It has become key technologies to solve the major problems in the fields of energy, water resources and environment. The application of membrane materials and equipment to the Chinese materia medica (CMM) industry can significantly improve the production efficiency. In this paper, through the analysis of the application of membrane materials and technology in foreign and domestic pharmaceutical industries, facing the industrial upgrading and green development of the application process of CMM industry, it is proposed to introduce the theory and method of material chemical engineering into the field of CMM, to carry out original research with independent intellectual property rights, and to construct a new membrane-based approach. The new separation procedure, separation process and exclusive equipment with separation technology as the core realize energy saving and emission reduction in the production process of CMM. Through expatiating on the basic research and engineering application of industrialization of separation process of CMM and its complex systems such as water extraction system and oil-water mixture system in the past 20 years, the project team provides theoretical basis and application demonstration for the design, integration, and application of new separation process of CMM based on special membrane technology.
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In order to analyze the law of membrane permeation of different alkaloids, seven traditional Chinese medicine alkaloids with different parent nucleus and substituent structures, including berberine, palmatine, sinomenine, matrine, oxymatrine, sophoridine, and tetrandrine, were prepared into the simulated solution with same molar concentration, and the membrane penetrating experiments with membrane RC1K and membrane RC5K were carried out. The dynamic transmittance, the total transmittance and the total adsorption rate of each substance were measured, and the scanning electron microscopy (SEM) images of the membrane surface before and after the membrane experiment were considered to predict and analyze the reason of differences in dynamic transmittance of different alkaloids. The results showed that there were significant differences in the dynamic transmittance of the chemical constituents of different alkaloids during penetrating the two membranes. The contamination degree on the surface of the membrane material was also different. The transmittance of the same compound through the RC5K membrane was larger than that through RC1K membrane. Within a certain range, the smaller the pore size of the membrane, the better the selective screening effect on the chemical constituents of traditional Chinese medicine. All the membrane surfaces were less polluted. The difference in transmittance between different substances on the same membrane showed a positive correlation with the difference in structural complexity, providing an experimental basis for the surface modification design in contamination control of membrane materials. In the design of membrane modified material, the surface properties of the membrane can be improved by grafting different polar groups, thereby changing the adsorption characteristics of the membrane surface. The pore size was designed accordingly to achieve the high transmittance and low pollution of the corresponding compounds.
Subject(s)
Berberine Alkaloids , Chemistry , Drugs, Chinese Herbal , Chemistry , Medicine, Chinese Traditional , PermeabilityABSTRACT
Objective To modify the existing preparation instrument for medical patch material to realize its scale and automatic production.Methods The instrument had its shaking table improved and a cylindrical processing system added with comprehensive analysis on raw materials and kinds of process flows.A spreading and fixation mechanism for animal materials was placed in the cylindrical processing system,which had the holes for liquid inlet and outlet respectively on its top and bottom.The cylindrical processing system was fixed to the base of the shaking table.Results The instrument enhanced preparation efficiency significantly,and had the raw material utilization rate increased by 20％,product qualification rate raised by 35％,preparation cycle reduced by 33％ and total cost saved by 40％.Conclusion The instrument behaves well in adaptability to multi animals,preparation process,inter-assay difference,raw material utilization rate,product qualification rate and cost reduction,which is of great significance to promote the clinical application of medical biological patch.
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Objective To investigate the influence of polyethylene glycol (PEG) on heparin release of heparinloaded polycaprolactone/polyethylene glycol (PCL/PEG) membranes used in artificial vascular peosthesis.Methods Heparin-loaded PCL/PEG membrane samples with different PEG mass contents of 0,0.5％,10％ and 15％ were prepared by blending method and freeze-drying technology.The influence of PEG on heparin release was experimental studied in vitro.The influence of PEG on the structural characteristics of the samples were investigated by X-ray diffraction,Fourier transform infrared spectrum and differential scanning calorimeter.Results The addition of PEG reduced the heparin release resistance.The results showed that the average release rate of heparin in the first day and the release amount for 34 d were improved.Both these parameters increased with the increase of PEG mass content.The X-ray diffraction,Fourier transform infrared spectroscopy and differential scanning calorimetry showed that the crystallinity of PCL membrane was slightly enhanced by the addition of heparin,but the overall effect was not significant.In addition,the addition of heparin could promote the crystalline grain growth of PEG,and a common distribution of heparin and PEG in the matrix was observed.Conclusions The heparin release control can be achieved by adjusting the PEG mass content in heparin-loading PCL/PEG membranes prepared by blending method and freeze-drying technology.The proposed samples may have anticoagulant effect,which can be expected to be used as small-diameter artificial vascular prosthesis material.
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Objective: To study the application of four kinds of hollow fiber ultrafiltration membranes by taking Qihong Maitong Injection (QMI) microfiltrated liquid as the research object. Methods: Polysulfone, polyether sulfone, polypropylene, and blended composite membranes with the entrapment relative molecular mass of 100000 for ultrafiltration were selected to determine the best appropriate ultrafiltration membrane material. The membrane flux of ultrafiltration was determined by taking the content of active ingredients (Astragalus total saponin, astragaloside IV, and hydroxy safflower yellow A), solid reduction rate, protein reduction rate, related substances, and pyrogen inspection of different membrane materials as the evaluation indexes. Results: The suitability of four different kinds of ultrafiltration membrane materials with the same entrapment relative molecular mass was different. The pure water flux recovery rates of polypropylene, polyether sulfone, and blended composite materials are higher than that of polysulfone material. The component permeation rates of polypropylene and polyether sulfone materials were higher, while the solid and protein reduction rates of polysulfone and blend compound materials were higher. For QMI, the ultrafiltration membrane with entrapment relative molecular mass of 100000 could effectively remove the pyrogen. Conclusion: The polypropylene-100000 ultrafiltration membrane could not only effectively remove the solid and high polymer material, but also keep the active ingredients. It is suitable for the purification of QMI.