醋酸羟丙基甲基纤维素琥珀酸酯的性能表征

 目的合成新型肠溶包衣材料醋酸羟丙基甲基纤维素琥珀酸酯(HPMCAS),并分析其结构特征和性能。方法采用红外光谱、紫外光谱、热重分析和化学分析等方法进行表征,测试HPMCAS在有机溶剂中的溶解情况、黏度、抗张强度和极限伸长率,并与日本的醋酸羟丙基甲基纤维素琥珀酸酯样品AS-LG进行比较。结果HPMCAS中酸性丁二酰基、乙酰基的含量与加入酸酐的量密切相关;二氯甲烷-乙醇等混合溶剂是HPMCAS的良溶剂;HPMCAS低于200℃时对热稳定,高于此温度后快速失重。结论其物化性质与日本样品AS-LG接近。     

补肾方含药血清促进PC12细胞增殖及其拮抗谷氨酸神经毒作用的研究

目的运用中药血清药理学方法研究补肾复方含药血清(BS)促进体外培养的PC12细胞增殖及其拮抗谷氨酸兴奋性神经毒损伤的作用.方法以MTT法观察BS对体外培养的PC12细胞活力的影响及其拮抗谷氨酸损伤的作用,采用流式细胞仪观察BS对谷氨酸所诱导PC12细胞凋亡的影响.结果 BS含药血清可以增强PC12细胞活力,拮抗谷氨酸的兴奋性神经毒作用且在20%浓度时作用最强,并且能够抑制谷氨酸诱导的PC12细胞早期凋亡.结论补肾方BS可能具有神经保护作用.     

恩七叶甜、恩五叶蜜与绞股蓝原变种成分分析及显著性测验

目的 :为合理开发利用药食两用植物绞股蓝提供依据 ;方法 :将恩七叶甜、恩五叶蜜两个新品种与绞股蓝原变种 (苦味 )按方差分析要求种植在相同的生态环境中给予相同的田间管理 ,同时播种和收获干全草进行成分分析 ;结果 :2个新品所含人参总皂苷、总氨基酸、维生素E、维生素B₁、维生素B₂ 分别高于绞股蓝原变种 33.3% ,34.3% ;11.8% ,4.7% ;76 % ,45 .8% ;46 % ,76 .1% ;41.2 % ,25 % ,均达到极显著水平 ;总糖分别低于绞股蓝原变种16.3% ,4.4 %。结论 :两个新品种不仅各有风味 ,适口性好 ,而且有效成分含量更高 ,应用领域更宽 ,市场需求量更大 ,医疗保健效果更好 ,更具有工业开发价值。     

经典名方中玄参的本草考证

通过查阅历代本草、医籍、方书及近现代文献资料，对经典名方中所用饴糖的名称、品种、原料及制作工艺进行了考证，为含有饴糖的经典名方开发利用提供依据。经考证可知，饴糖之名历代多源于其形态、质地、制法、原料及产地。古代所用饴糖根据质地不同，主要分为软、硬两类，湿软如蜜者称为“饴”或“胶饴”，质硬色白的则称为“饧”“糖”，现代则多称为麦芽糖，入药仅用胶饴，饧则多作食用；历代药用胶饴推崇糯米（来源于Oryza sativa var. glutinosa）为原料，以大麦Hordeum vulgare制蘖，经过发酵、煎煮、浓缩制备而成，而粟米（来源于Setaria italica var. germanica）、黍Panicum miliaceum等其他谷物为原料制成的饴糖品质次之。2020年版《中华人民共和国药典》未收录饴糖，收载了药用辅料麦芽糖，为纯度较高的结晶粉；但国家食品标准与地方炮制规范中收录了饴糖。基于考证结果，建议经典名方开发中所用胶饴可参考GB/T 20883—2017中的麦芽糖浆，并明确以糯米、大麦为原料。     

Imprinting Technology for Effective Sorbent Fabrication: Current State-of-Art and Future Prospects

In the last 10 years, we have witnessed an extensive development of instrumental techniques in analytical methods for determination of various molecules and ions at very low concentrations. Nevertheless, the presence of interfering components of complex samples hampered the applicability of new analytical strategies. Thus, additional sample pre-treatment steps were proposed to overcome the problem. Solid sorbents were used for clean-up samples but insufficient selectivity of commercial materials limited their utility. Here, the application of molecularly imprinted polymers (MIPs) or ion-imprinted polymers (IIPs) in the separation processes have recently attracted attention due to their many advantages, such as high selectivity, robustness, and low costs of the fabrication process. Bulk or monoliths, microspheres and core-shell materials, magnetically susceptible and stir-bar imprinted materials are applicable to different modes of solid-phase extraction to determine target analytes and ions in a very complex environment such as blood, urine, soil, or food. The capability to perform a specific separation of enantiomers is a substantial advantage in clinical analysis. The ion-imprinted sorbents gained interest in trace analysis of pollutants in environmental samples. In this review, the current synthetic approaches for the preparation of MIPs and IIPs are comprehensively discussed together with a detailed characterization of respective materials. Furthermore, the use of sorbents in environmental, food, and biomedical analyses will be emphasized to point out current limits and highlight the future prospects for further development in the field.     

Recent progress and prospects in the electrode materials of flexible sodium-ion battery

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In vitro study of a modified sagittal split osteotomy fixation technique of the mandible: a mechanical test

This study was performed to evaluate the compressive mechanical strength of rigid internal fixation (RIF) using 1.5-mm L-shaped plates fixed with monocortical screws in sagittal split osteotomy (SSO). Thirty synthetic hemimandibles, which had all undergone a 5-mm advancement, were divided into three groups: three 12-mm bicortical titanium screws were placed in an inverted L pattern in group A; one straight 2.0-mm system spaced titanium plate fixed with four 5-mm monocortical screws was used in group B; two 1.5-mm system L-shaped titanium plates, each fixed with four 5-mm monocortical screws, were used in group C. The models were subjected to compressive and progressive mechanical tests with forces applied in the area between the second premolar and first molar to verify resistance in Newtons (N). A displacement speed of 1 mm/min was applied, with a maximum 10 mm displacement of the distal segment or until disruption of the fixation. The deformity and/or eventual rupture of the plates were evaluated, and consequently their technical stability was determined. The results showed that the modified fixation technique tested in this study on synthetic mandibles resulted in adequate stability and superior mechanical behaviour compared to simulated osteosynthesis with the use of a straight 2.0-mm titanium plate.     

Development of a lyophilized soybean paste certified reference material for the analysis of ochratoxin A

A certified reference material (CRM) [²KRISS CRM # 108-10-018] for the analysis of ochratoxin A (OTA) in doenjang (fermented soybean paste and popular food in Korea) was produced to ensure the reliability of analytical results in testing laboratories. A home-made doenjang was chosen as a raw material after testing its OTA level. The raw material was freeze-dried, pulverized, sieved and homogenized. An isotope-dilution-liquid chromatography/tandem mass spectrometric method (ID-LC/MS/MS) which was previously developed and validated in this laboratory was used as a higher-order reference method for characterization, homogeneity studies, and short-term stability studies. The CRM had good between-bottle homogeneity with 0.56% relative standard deviation among 10 selected units. The stability of the CRM at −70 °C (the storage condition in our laboratory) and at −20 °C (the possible storage temperature at user sites) were tested for up to 8 months. No change in the OTA content was observed within the measurement uncertainty. The stability of the CRM at room temperature (for regular use and transportation) was also tested and confirmed. The certified value was (49.50 ± 1.17) μg/kg, where the expanded uncertainty was in the confidence level of 95%.