Preparation of Naringenin Nanosuspension and Its Antitussive and Expectorant Effects

Naringenin (NRG) is a natural flavonoid compound abundantly present in citrus fruits and has the potential to treat respiratory disorders. However, the clinical therapeutic effect of NRG is limited by its low bioavailability due to poor solubility. To enhance the solubility, naringenin nanosuspensions (NRG-NSps) were prepared by applying tocopherol polyethylene glycol succinate (TPGS) as the nanocarrier via the media-milling method. The particle size, morphology, and drug-loading content of NRG-NSps were examined, and the stability was evaluated by detecting particle size changes in different physiological media. NRG-NSps exhibited a flaky appearance with a mean diameter of 216.9 nm, and the drug-loading content was 66.7%. NRG-NSps exhibited good storage stability and media stability. NRG-NSps presented a sustainable release profile, and the cumulative drug-release rate approached approximately 95% within 7 d. NRG-NSps improved the antitussive effect significantly compared with the original NRG, the cough frequency was decreased from 22 to 15 times, and the cough incubation period was prolonged from 85.3 to 121.6 s. Besides, NRG-NSps also enhanced expectorant effects significantly, and phenol red secretion was increased from 1.02 to 1.45 μg/mL. These results indicate that NRG-NSps could enhance the bioavailability of NRG significantly and possess a potential clinical application.     

Glyceric Prodrug of Ursodeoxycholic Acid (UDCA): Novozym 435-Catalyzed Synthesis of UDCA-Monoglyceride

Bile acids (BAs) are a family of steroids synthesized from cholesterol in the liver. Among bile acids, ursodeoxycholic acid (UDCA) is the drug of choice for treating primary biliary cirrhosis and dissolving cholesterol gallstones. The clinical effectiveness of UDCA includes its choleretic activity, the capability to inhibit hydrophobic bile acid absorption by the intestine under cholestatic conditions, reducing cholangiocyte injury, stimulation of impaired biliary output, and inhibition of hepatocyte apoptosis. Despite its clinical effectiveness, UDCA is poorly soluble in the gastro-duodeno-jejunal contents, and pharmacological doses of UDCA are not readily soluble in the stomach and intestine, resulting in incomplete absorption. Indeed, the solubility of 20 mg/L greatly limits the bioavailability of UDCA. Since the bioavailability of drug products plays a critical role in the design of oral administration dosages, we investigated the enzymatic esterification of UDCA as a strategy of hydrophilization. Therefore, we decided to enzymatically synthesize a glyceric ester of UDCA bile acid to produce a more water-soluble molecule. The esterification reactions between UDCA and glycerol were performed with an immobilized lipase B from Candida antarctica (Novozym 435) in solvent-free and solvent-assisted systems. The characterization of the UDCA-monoglyceride, enzymatically synthesized, has been performed by ¹H-NMR, ¹³C-NMR, COSY, HSQC, HMBC, IR, and MS spectroscopy.     

熊去氧胆酸生产中相关物质的分析

建立了HPLC-示差折光检测器外标法测定熊去氧胆酸中4种特殊杂质及其他有关物质含量的方法,结果表明各样品在测定范围内线性关系良好(r=0.999 1~0.999 6),方法回收率、精密度、稳定性、重复性均符合要求,适用于熊去氧胆酸生产的质量控制。     

Anticancer Effects of Ursi Fel Extract and Its Active Compound,Ursodeoxycholic Acid,in FRO Anaplastic Thyroid Cancer Cells

Anaplastic thyroid cancer (ATC) is one of the most fatal human malignancies. Ursi Fel (UF) is the bile of a brown bear that has been traditionally used for heat clearance and toxin relief in Korean and Chinese medicines. In this study, we determined the anticancer effects of a UF extract and its active compound, ursodeoxycholic acid (UDCA), in FRO human ATC cells. FRO cells were treated with UF extract and UDCA at different concentrations for various durations. Cell viability was measured using an MTT assay. Cell apoptosis was investigated by flow cytometric analysis following Annexin V and propidium iodide (PI) staining, and Hoechst staining was used to observe nuclear fragmentation. The expression of pro-apoptotic (Bax, caspase-3, cytochrome c, and PARP), anti-apoptotic (Bcl-2), and angiogenetic (TGF-β, VEGF, N-cadherin, and sirtuin-1) proteins and the phosphorylation of Akt and mechanistic target of rapamycin (mTOR) were determined by western blot analysis. Treatment with UF extract at 10, 25, and 50 μg/mL and UDCA at 25, 50, and 100 μM/mL significantly inhibited the growth of FRO cells in a dose-dependent manner. Flow cytometry and Hoechst staining revealed an increase in the apoptosis of FRO cells mediated by UF extract and UDCA in a dose-dependent manner. UF extract (25 and 50 μg) and UDCA (50 and 100 μM) significantly increased the expression of Bax, caspase-3, cytochrome c, and PARP and inhibited the expression of Bcl-2, TGF-β, VEGF, N-cadherin, and sirtuin-1 in FRO cells. Furthermore, UF extract and UDCA treatment stimulated Akt phosphorylation and inhibited mTOR phosphorylation in these cells. These results indicate that UF extract and UDCA exert anticancer properties in FRO cells by inducing apoptosis and inhibiting angiogenesis via regulating the Akt/mTOR signaling pathway.     

硫酸镧与氨基酸配合物的合成及表征

合成了七种见文献报道的硫酸镧与氨基酸的配合物，通过化学分析，元素分析，红外光谱和热分析等，确定了所得配合物的组成为Ｌａ２（ＡＡ）ｎ（ＳＯ４）３．ｘＨ２Ｏ（ＡＡ＝氨基酸；ｎ＝４，４，６；ｘ＝４，６，８），并对它们的荧光光谱等进行了研究。     

Dawson结构钼磷酸的合成与表征

合成了H_6P_2Mo_(18)O_(62)杂多酸及其四丁基铵盐和四丁基鏻盐,用IR、~(31)P NMR、GV等手段核查其纯度并研究了热稳定性、酸性和氧化还原性。结果表明,Dawson结构钼磷酸较Keggin结构钼磷酸有更强的氧化性。     

Preparation and Characterization of Molybdotungstoniobogermanic Acid

Recently,thepreparationandpropertiesofheteropolycomplexeshaveincreasinglyattractedattentioninvariousfieldsofchendstIy,especiallyincatalysicapplicationsfortheiruniqueproperties'.Sincel988,thestudiesoffour-baseheteropolycomplexeswiththeKegginstructurehavebeenreported.Asthespecialbifunctionalcatalyticand.-lantisepsispropertyoftheheteropolycomplexescontainingniobium',andsofarthemolybdotungstoniobogermanicheteropolycomplexesinwhichthecentralatomisgermanium,havenotbeenreportedyet,ennea-tungsto-bi-mo…     

新型固体酸SO42-/Al2O3-Al 的制备与表征

采用铝阳极氧化法制备了A12O3-Al一体型载体．并通过浸渍硫酸的方法制备了新型固体酸SO4^2-／Al2O3-Al催化剂．采用BET、XRD、XPS和NH3-TPD对其结构和酸性进行了表征．结果表明，该催化剂具有合适的孔结构．Al2O3-Al载体为无定形结构．NH3-TPD结果表明．该催化剂同时具有弱酸及强酸位．用乙酸／乙醇酯化催化反应评估了该固体酸的催化性能．     

酸掺杂聚苯胺修饰酞菁铜有机半导体气敏材料的制备及表征

本文以4-硝基邻苯二腈和对甲基苯酚为苯环源物质合成酞菁铜(CuPc),以苯胺为聚苯胺(PANT)源物质,并通过掺杂高氯酸(硫酸或硝酸)与CuPc聚合形成一种新的有机半导体材料酸掺杂聚苯胺修饰酞菁铜(CuPcxPANI1-x).通过质谱、红外光谱、紫外可见光谱、差热失重等手段表征,结果表明:酞菁分子碎片分子量经质谱分析确...     

Preparation and Characterization of Pure Thiosulfuric Acid

Pure thiosulfuric acid has not been prepared yet, although it is described in most textbooks of inorganic chemistry. Furthermore, no experimental evidence for the structure of thiosulfuric acid is known. Theoretical calculations predict the (SH)(OH) tautomer to be more stable than the (OH)(OH) tautomer. In this work we present the synthesis and spectroscopical characterization of pure thiosulfuric acid. X₂S₂O₃ (X = H, D) was obtained from the reaction of dry Na₂S₂O₃ with anhydrous HF at –60 °C. The experimental vibrational and NMR spectra together with quantum chemical calculations provide evidence for the predicted (SH)(OH) tautomeric structure.     

Preparation and Characterization of Protonated Fumaric Acid

Fumaric acid was reacted with the binary superacidic systems HF/SbF₅ and HF/AsF₅. The O,O'-diprotonated [C₄H₆O₄]²⁺([MF₆]^–)₂ (M = As, Sb) and the O-monoprotonated [C₄H₅O₄]⁺[MF₆]^– (M = As, Sb) species are formed depending on the stoichiometric ratio of the Lewis acid to fumaric acid. The colorless salts were characterized by low-temperature vibrational spectroscopy. In case of the hexafluoridoantimonates single-crystal X-ray structure analyses were carried out. The [C₄H₆O₄]²⁺([SbF₆]^–)₂ crystallizes in the monoclinic space group C2/c with four formula units per unit cell and [C₄H₅O₄]⁺[SbF₆]^– crystallizes in the triclinic space group P1 with one formula unit per unit cell. The protonation of fumaric acid does not cause a notable change of the C=C bond length. The experimental data are discussed together with quantum chemical calculations of the cations [C₄H₆O₄ · 4 HF]²⁺ and [C₄H₆O₄ · 2 H₂CO · 2 HF]²⁺.     

乙酰化甲壳素膜的制备及表征

本文报道了加入二氯甲烷可使甲壳素的乙酰化反应更顺利进行,并提高了产物的乙酰化度,通过红外、X射线衍射分析、拉伸等方法对乙酰化甲壳素膜的结晶结构和力学性能作了表征和测定。     

兽疫链球菌变异株产生的透明质酸的纯化及表征

用N-甲基-N′-硝基-N-亚硝基胍(NTG)对兽疫链球菌进行诱变,获得高产菌株.经过对该菌株的发酵培养,将产生的多糖经Savage法、季铵复合物沉淀法、DEAE-纤维素(DE52)离子交换层析法及SephadexG-75凝胶过滤法分离纯化.纯化的多糖结构经化学组成分析、核磁共振波谱、红外光谱及圆二色谱鉴定,证明了诱变得到的高产菌株(StreptococcuszooepidemicusJ18)再经发酵,得到的多糖为透明质酸.通过刚果红实验证明了透明质酸的构象为单股螺旋结构,其平均分子量约为1.16×10⁶.     

活性炭负载磷钨酸催化剂的表征及其催化性能

研究了活性炭负载磷钨酸催化剂的表征及在丁基多苷合成中的催化性能.活性炭负载磷钨酸催化剂采用浸渍法制备,并用FT-IR光谱、XRD光谱、SEM等手段进行了表征.结果表明,磷钨酸负载到活性炭后保持了原有的Keggin结构,它在载体上的吸附过程可以分为单分子吸附、多分子吸附和体相堆积三个阶段.在丁基多苷合成反应中,催化剂负载量、磷钨酸溶脱量、葡萄糖转化率之间有较复杂的关系.杂多酸溶脱量随负载量增大而增大,转化率与杂多酸溶脱量之间没有直接联系.催化剂负载量在5%到60%之间变化时,控制催化活性的主要因素分别是催化剂酸量、比表面积、游离的杂多酸量.最佳负载量为20%.     

含胆酸高分子化合物的制备和特性*

胆酸是哺乳动物体内合成的一种天然化合物,具有特殊的分子结构和优良的生物适应性。由胆酸合成的高分子化合物保持了胆酸的部分性质,如双亲性、手性、侧基反应活性和自组装性能等。在化学和药学领域,含胆酸高分子材料具有重要的应用价值。本文从自由基聚合形成的含胆酸高分子化合物、胆酸修饰的高分子化合物和胆酸聚合物等几个方面综述了含胆酸高分子化合物的制备和特性,并对胆酸在高分子材料方面的新用途作了展望。     

牛磺熊去氧胆酸的合成研究

以熊去氧胆酸为原料，先与氯甲酸乙酯形成混酐，再与牛磺酸反应合成牛磺熊去氧胆酸。通优化反应条件、简化后处理等工艺改进，提高了收率，得到了较高纯度的结晶产品。     

阳离子型微乳液聚合丙烯酰胺的表征

自从Hoar[1]和Schulman[2]利用乳化剂、水和油制得均一透明的微乳液以来,微乳液在许多领域中得到广泛应用.Candau[3,4]通过微乳液聚合得到分子量很高(105～106)的纳米级聚合物粒子,且聚合物分子链采取紧密缠绕的构象.Antonietti[5]在对苯乙烯微乳液聚合的研究报道中认为,聚合物分子链是以一种类似于网状交联结构的形态存在的,这些结果表明,通过微乳液聚合所得聚合物可能存在着一些特殊的性质.本文采用阳离子型乳化剂十六烷基三甲基溴化铵(CTAB)和脂肪族醇助乳化剂制备的油包水(W/O)型反相微乳液体系来聚合丙烯酰胺(Am),并与使用相同乳…     

磷钨酸/SiO2负载化光催化剂的制备与表征

以溶胶–凝胶法合成的SiO2作载体,固载磷钨酸制得负载化磷钨酸光催化剂,用XRD、FT-IR、UV-Vis-DRS等方法表征了催化剂的理化性能。结果表明,所制备的负载化磷钨酸催化剂对甲基橙的光催化降解反应具有较好的催化性能。     

沸石膜的合成、表征与应用

综述了沸石膜的合成、表征及应用。沸石膜合成最常用的方法为水热合成法,并相继发展了二次生长和微波合成法。XRD、SEM、EPMA及气体渗透为表征沸石膜常用的手段。沸石膜在分离、膜反应、催化及光学材料等方面具有广阔的应用前景。最后对沸石膜的发展进行了展望。     

由醋酸去氢表雄酮合成熊去氧胆酸

探索了用植物源商业原料合成熊去氧胆酸的新方法. 以醋酸去氢表雄酮为原料, 以区域选择性烯丙位氧化、 Mistunbu反应和Luche还原为关键步骤, 通过9步反应, 以38.6%的总收率合成了熊去氧胆酸. 其中, 关键中间体4由化合物3经改进的烯丙位氧化反应以较高产率获得. 对关键的烯丙基氧化反应的条件进行了优化, 包括溶剂、 氧化剂和反应温度. 该方法原料易得、 产率较高, 并且有效地避免了动物源性原料的风险, 易于实现规模化合成, 因而具有较高的应用价值.