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1.
In the 0.1 mol · L?1 hydrochloric acid solution, oxymatrine reacted with tungstosilicic acid to form a 2:1 ion-association complexes. This results in a great enhancement of resonance Rayleigh scattering. The maximum resonance Rayleigh scattering wavelength was located at 393 nm. Resonance Rayleigh scattering intensity was proportional to the concentration of oxymatrine in the range of 1.5–26.4 µg · mL?1, and the detection limit (3σ) was 0.23 µg · mL?1. The optimum conditions and the effects of coexisting substances on the reaction were investigated. The method shows a wide linear range and high sensitivity, and was applied to the determination of oxymatrine in marine capsules and human urine samples with satisfactory results. Therefore, a highly sensitive, simple, and quick method has been developed for the determination of oxymatrine.  相似文献   
2.
白小红  杨雪  陈璇  王琳慧 《分析化学》2008,36(2):182-186
建立了液相微萃取/后萃取-高效液相色谱法测定中药苦参、复方苦参注射液中氧化苦参碱和苦参碱含量的方法。利用自制的微萃取装置,选择异丙醇为萃取有机溶剂,2.00 mL NaOH(pH9)为供相,HCl(pH4)为接受相,聚丙烯腈纤维的长度为10 cm,搅拌速度为1500 r/min,萃取时间为30 min。萃取完成后,经高效液相色谱仪分析,测得氧化苦参碱和苦参碱线性范围分别为11~437 mg/L和10~433 mg/L;检出限均为1.0mg/L;相对标准偏差分别小于9.4%和6.7%。复方苦参注射液中氧化苦参碱和苦参碱的平均回收率分别为83.0%~116.1%和108.8%~117.8%;苦参药材中氧化苦参碱的平均回收率为104.3%~114.7%。本方法有机溶剂用量少,可有效去除复杂机体的干扰,测得结果满意。  相似文献   
3.
This study focuses on the fabrication, characterization and anticancer properties of biocompatible and biodegradable composite nanofibers consisting of poly(vinyl alcohol) (PVA), oxymatrine (OM), and citric acid (CA) using a facile and high-yield centrifugal spinning process known as Forcespinning. The effects of varying concentrations of OM and CA on fiber diameter and molecular cross-linking are investigated. The morphological and thermo-physical properties, as well as water absorption of the developed nanofiber-based mats are characterized using microscopical analysis, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In vitro anticancer studies are conducted with HCT116 colorectal cancer cells. Results show a high yield of long fibers embedded with beads. Fiber average diameters range between 462 and 528 nm depending on OM concentration. The thermal analysis results show that the fibers are stable at room temperature. The anticancer study reveals that PVA nanofiber membrane with high concentrations of OM can suppress the proliferation of HCT116 colorectal cancer cells. The study provides a comprehensive investigation of OM embedded into nanosized PVA fibers and the prospective application of these membranes as a drug delivery system.  相似文献   
4.
A sensitive and reliable ion-paired high-performance liquid chromatographic method has been established for the simultaneous quantification of six major active ingredients, namely baicalin, baicalein, wogonin, oxysophocarpine, oxymatrine and matrine in the Chinese herbal preparation, Sanwu-Huangqin-Tang. HPLC analyses were performed on a Phenomenex luna C18 column with mobile phase of methanol–acetonitrile–aqueous phosphoric acid at a flow rate of 0.9 mL min−1. The complete separation was achieved within 35 min for the six target constituents. A good linear regression relationship between peak-areas and concentrations was obtained over the range of 12.10–242.0 μg*mL−1 for baicalin, 5.05–101.0 μg*mL−1 for baicalein, 0.95–19.0 μg*mL−1 for wogonin, 2.75–55.0 μg*mL−1 for oxysophocarpin, 2.75–55.0 μg*mL−1 for oxymatrine and 4.90–98.0 μg*mL−1 for matrine, respectively. The repeatability was evaluated by intra- and inter-day assays with relative standard deviation (RSD) being less than 5.1%. The recoveries, measured at three concentration levels, varied from 93.8 to 102.1%. The assay was successfully applied for determination of six bioactive compounds in Sanwu-Huangqin-Tang. The interaction of chemical constituents was observed when the herbs were used in compatibility. The results indicated that the developed assay method was rapid, accurate and could be readily utilized as a quality control method for Sanwu-Huangqin-Tang.  相似文献   
5.
Following a detailed study, a reversed-phase high performance liquid chromatographic method (HPLC) has been developed and validated for analysis of three bioactive alkaloids, matrine, sophoridine and oxymatrine, in Sophora flavescens Ait. HPLC separation of the alkaloids was performed on a Kromasil C(18) column and detected by ultraviolet absorbance at 208 nm. The column temperature was maintained at 40 degrees C. A mobile phase composed of 0.01 mol/L KH(2)PO(4) buffer-methanol-triethylamine in the ratios 94:6:0.01 (v/v) was found to be the most suitable for this separation at a fl ow-rate of 1.0 mL/min and enabled the baseline separation of the three analytes free from interferences with isocratic elution. The analysis time was 24 min per injection. The calibration was linear in the range of 0.2-120.0 micro g/mL for matrine, 0.2-115.2 micro g/mL for sophoridine and 0.2-110.4 micro g/mL for oxymatrine, respectively. For assaying Sophora Flavescens Ait. samples, the relative standard deviations were 2.0% for matrine, 2.8% for sophoridine and 1.8% for oxymatrine analysis. The average recoveries of matrine, sophoridine and oxymatrine were 93.9, 95.3 and 93.5% for the Sophora flavescens Ait. samples, respectively. The method has been successfully applied to the simultaneous determination of matrine, sophoridine and oxymatrine in Sophora Flavescens Ait. samples collected in different habitats.  相似文献   
6.
Double‐templated molecularly imprinted polymers with specific recognition of three matrine‐type alkaloids were prepared using matrine and oxymatrine as the template molecules. An approach based on double‐templated molecularly imprinted solid‐phase extraction coupled with high‐performance liquid chromatography and tandem mass spectrometry was then developed to extract and purify matrine, oxymatrine, and sophocarpine from Sophora moorcroftiana in the Tibetan plateau herbs. The polymers were characterized by Fourier‐transform infrared spectroscopy and scanning electron microscopy. Their adsorption characteristics were evaluated using adsorption kinetics, isotherms, selectivity, and recycling experiments. This polymer exhibited excellent molecular recognition ability and good selectivity. The obtained polymers as adsorbent was further used for the determination of three matrine‐type alkaloids coupled to high‐performance liquid chromatography with tandem mass spectrometry, the recoveries of three matrines spiked at three concentration levels in samples were 73.25–98.42% (n = 5) with a relative standard deviation less than 6.82%. The limits of detection for the method were 9.23–15.42 μg/kg (S/N = 3). This proposed method was assessed to be an effective method for simultaneous extraction, isolation, and identification of matrine, oxymatrine, and sophocarpine from Sophora moorcroftiana.  相似文献   
7.
苦参碱和氧化苦参碱电子结构与药性的关系   总被引:12,自引:0,他引:12  
用量子化学从头算和半经验方法研究了苦参碱和氧化苦参碱的电子结构对药理活性的影响。结果表明:苦参碱与氧化苦参相比较,在最低能量的构象结构、分子轨道结构、电荷结构和原子间键序方面相近,而在分子轨道能级和原子电荷数值方面有明显差异。从立体作用、轨道作用和电性作用方面来看,氧化苦参碱比苦参碱具有更强的作用,由此预测,氧化苦参碱的药理活性高于苦参碱。  相似文献   
8.
苦参配方颗粒的高效液相色谱指纹图谱研究及定量分析   总被引:1,自引:0,他引:1  
王一奇  马源源  吴雁  张跃飞  李发美 《分析化学》2006,34(12):1791-1793
研究了苦参配方颗粒的指纹图谱和含量测定。采用高效液相色谱法,在C18柱上以乙腈-磷酸氢二钠水溶液(20 mmol/L,磷酸调pH 7.1)进行梯度洗脱,柱温35℃,检测波长220 nm,用指标成分氧化苦参碱、氧化槐果碱和苦参碱进行了定位,并在同一色谱条件下同时测定了它们的含量。确定了15个共有峰,其中7、8和11号峰分别为氧化苦参碱、氧化槐果碱和苦参碱。10批样品平均相似度为0.99以上,三个成分的含量分别为:氧化苦参碱50.0~79.8 mg/g;氧化槐果碱13.5~18.1 mg/g;苦参碱16.5~30.1 mg/g。结果表明:指纹图谱与指标成分含量测定相结合,可提高苦参配方颗粒的内在质量控制水平。  相似文献   
9.
氧化苦参碱与牛血清白蛋白相互作用的热力学研究   总被引:1,自引:0,他引:1  
徐香玉  孙祥军  刘敏  孙得志  李林尉 《化学学报》2009,67(18):2155-2158
在298.15 K下, 应用等温滴定量热法和圆二色谱法研究了氧化苦参碱(OMT)与牛血清白蛋白(BSA)的相互作用, 并讨论了二者结合过程热力学性质的改变. 研究结果表明, BSA大分子上存在可结合OMT分子的两类位点. OMT分子与第一类位点相结合时, 结合过程的平衡常数、标准摩尔焓变和标准摩尔吉布斯自由能变分别为 =(2.14±0.31)×105, =(-1.07±0.50) kJ•mol-1, =(-30.4±0.4) kJ•mol-1, 最大可结合位点数为 N1=(10.0±0.2), 该过程是以熵驱动为主的焓熵协同驱动过程. OMT 分子与第二类位点相结合时, =(6.84±0.32)×103, =(1.91±0.03) kJ•mol-1, =(-21.9±0.4) kJ•mol-1, N2=(25.0±0.3), 该过程是熵驱动过程. 圆二色谱测试结果表明, 两类结合过程中, OMT与BSA的相互作用均导致了蛋白质二级结构构象及不同结构单元相对含量的变化.  相似文献   
10.
建立反相液相色谱法测定苦参中苦参碱和氧化苦参碱含量的方法。提取溶剂为乙醇,选择C18色谱柱,以甲醇–水–三乙胺溶液(55∶45∶0.2)为流动相,流量为0.8 mL/min,紫外检测器波长为210 nm。苦参碱和氧化苦参碱的质量浓度在10~200 mg/L范围内均与其色谱峰面积呈良好的线性,线性相关系数均大于0.999,检出限分别为0.05,0.1 mg/L。苦参碱和氧化苦参碱的加标回收率分别为98.47%,97.89%,测定结果的相对标准偏差分别为1.32%,1.08%(n=6)。该方法操作简便,干扰少,灵敏度高。  相似文献   
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