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91.
Xi-Yang Tang Zi-Qin Dai Jia-Xing Zeng Zi-Ting Li Cai-Lian Fan Zhi-Hong Yao Xin-Sheng Yao Yi Dai 《Journal of separation science》2022,45(13):2177-2189
In the present study, a specific and sensitive approach using ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry was developed and validated for the quantitative analysis of 14 constituents in rat plasma, liver, and heart. The method was fully validated and successfully applied to pharmacokinetic, hepatic disposition, and heart tissue distribution studies of 14 compounds after the oral administration of Qi-Li-Qiang-Xin capsule. Ginsenoside Rb1, alisol A, astragaloside IV, and periplocymarin were found to be highly exposed in rat plasma, while toxic components such as hypaconitine, mesaconitine, and periplocin had low circulation levels in vivo. Moreover, sinapine thiocyanate, neoline, formononetin, calycosin, and alisol A exhibited significant liver first-pass effects. Notably, high levels of alisol A, periplocymarin, benzoylmesaconine, and benzoylhypaconine were observed in the heart. Based on high exposure and appropriate pharmacokinetic features in the systemic plasma and heart, astragaloside IV, ginsenoside Rb1, periplocymarin, benzoylmesaconine, benzoylhypaconine, and alisol A can be considered as the main potentially effective components. Ultimately, the results provide relevant information for discovery of effective substances, as well as further anti-heart failure action mechanism investigations of Qi-Li-Qiang-Xin capsule. 相似文献
92.
Jun Chen Fei Zhu Meiling Pan Qing Liu Lin Chen Yi Tao 《Journal of separation science》2022,45(11):1952-1959
Semens of Astragali Complanati own anti-erectile dysfunction effect; however, the components which contribute to the anti-erectile dysfunction effect remain unclear. This work raised a strategy that integrates liquid chromatography coupled mass spectrometry-based quantitative analysis, anti-erectile dysfunction assessment on impotent rats, and their relationship analysis for pinpointing anti-erectile dysfunction components from semens of Astragali Complanati. For simultaneous quantification of seven major components in raw and salt-processed semens of Astragali Complanati, an accurate and reliable liquid chromatography–mass spectrometry method was developed under multiple reaction monitoring mode. Of note, chloramphenicol was employed as the internal standard. The method showed good linearity and repeatability, where the recovery rates of each component ranged from 98.1 to 104.7%, and the precisions of intra- and interday were all within 3.4%. The method has been used for quantification of the seven major components in 10 batches of raw and salt-processed semens of Astragali Complanati. Then, the anti-erectile dysfunction effects of raw and salt-processed semens of Astragali Complanati were evaluated on impotent rats. Gray relationship analysis and partial least squares regression were combined for elucidating the relationship. As a result, complanatuside, astragalin, complanatoside B, and kaempferol were found to be responsible for anti-erectile dysfunction effect of Astragali Complanati. 相似文献
93.
Yan-Zheng Zhang Juan-Juan Si Shan-Shan Li Guo-Zhi Zhang Shuai Wang Huo-Qing Zheng Fu-Liang Hu 《Molecules (Basel, Switzerland)》2021,26(9)
Honey has good antimicrobial properties and can be used for medical treatment. The antimicrobial properties of unifloral honey varieties are different. In this study, we evaluated the antimicrobial and antioxidant activities of nine kinds of Chinese monofloral honeys. In addition, headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) technology was used to detect their volatile components. The relevant results are as follows: 1. The agar diffusion test showed that the diameter of inhibition zone against Staphylococcus aureus of Fennel honey (21.50 ± 0.41 mm), Agastache honey (20.74 ± 0.37 mm), and Pomegranate honey (18.16 ± 0.11 mm) was larger than that of Manuka 12+ honey (14.27 ± 0.10 mm) and Manuka 20+ honey (16.52 ± 0.12 mm). The antimicrobial activity of Chinese honey depends on hydrogen peroxide. 2. The total antioxidant capacity of Fennel honey, Agastache honey, and Pomegranate honey was higher than that of other Chinese honeys. There was a significant positive correlation between the total antioxidant capacity and the total phenol content of Chinese honey (r = 0.958). The correlation coefficient between the chroma value of Chinese honey and the total antioxidant and the diameter of inhibition zone was 0.940 and 0.746, respectively. The analyzed dark honeys had better antimicrobial and antioxidant activities. 3. There were significant differences in volatile components among Fennel honey, Agastache honey, Pomegranate honey, and Manuka honey. Hexanal-D and Heptanol were the characteristic components of Fennel honey and Pomegranate honey, respectively. Ethyl 2-methylbutyrate and 3-methylpentanoic acids were the unique compounds of Agastache honey. The flavor fingerprints of the honey samples from different plants can be successfully built using HS-GC-IMS and principal component analysis (PCA) based on their volatile compounds. Fennel honey, Agastache honey, and Pomegranate honey are Chinese honey varieties with excellent antimicrobial properties, and have the potential to be developed into medical grade honey. 相似文献
94.
95.
该文基于酶辅助靶标循环信号放大策略构建了用于黄曲霉毒素B1(AFB1)高灵敏检测的化学发光适体传感器。以G-四链体/氯化血红素DNA酶为信号分子设计了免标记的适体探针H1-S1和发夹探针H2。适体探针结合目标AFB1,在核酸外切酶I辅助下,触发靶标循环反应产生发夹H1。发夹H1与H2杂交,释放出完整的G-四链体序列,并进一步与氯化血红素结合形成G-四链体/氯化血红素DNA酶。DNA酶通过催化氧化鲁米诺-H2O2化学发光体系产生化学发光信号,实现AFB1的放大检测。在最优实验条件下,化学发光强度与AFB1质量浓度的对数在0.001~100 ng/mL范围内呈良好的线性关系,相关系数(r2)为0.9955,检出限为0.93 pg/mL,回收率为93.7%~107%。该适体传感器操作简单、灵敏度高、特异性好,在黄曲霉毒素污染检测方面具有良好的应用前景。 相似文献
96.
The interband and intraband radiation from the n-InGaAs/GaAs heterostructures with the double and triple tunnel coupled and selectively doped quantum wells (QWs), which is appeared under the lateral electric field and in the presence of hole injection from the anode contact, has been investigated. A steep increase of the interband radiation intensity was found at the fields of E≥1.7 kV/cm. This effect should be related to the big lifetime of the injected charge carriers (~10−6 s) which exceeds by three orders of magnitude the lifetime in the similar bulk direct-band semiconductor. Its reason lies in spatial separation of the injected holes and electrons between coupled wells, firstly, by the built-in transverse electric field between wells and, secondly, due to the real-space transfer of carriers heated by the lateral electric field from the wide well to the narrow δ-doped one. Furthermore, an increase of the carrier concentration due to injection leads to an increase of that transition intensity and, consequently, to an intensity increase of the radiative intersubband transitions of carriers in QWs which results in a steep intensity increase of the far (50–120 µm) infrared radiation. 相似文献
97.
"中药微量元素数据"分为植物药、动物药、生物甲壳药、矿物药和中成药刊出,其中又细分为解表药、泻下药、清热药、利水渗湿药、祛风湿药、温里祛寒药、芳香化湿药、理气药、理血药、补养药、固涩药、化痰止咳药、消导药、熄风镇痛药、养心安神药、芳香开窍药、外用药、驱虫药、各类中药煎煮液。
检测的中药747种,共6 780味。每种药包括药名、学名、科属、部位、产地、元素含量、分析方法和文献来源等8个内容。以表格形式表示。每味药物最多测定38种元素,最少测定4种元素,平均测定17种元素,共展示出的元素数据约12万个。
每一个数据含义非常深刻,如序号为113的黄芩,共测定河北、山西、辽宁、黑龙江、山东、云南、四川、河南、吉林、陕西、甘肃、内蒙古、江苏等50个不同产地黄芩中的20种元素。又如序号为114的猕猴桃,共测定其中花、果、叶、枝、茎、根、皮、汁等8个不同部位中的23种元素。从元素的角度去研究中药不同产地、不同部位的药用功效,很有科研价值和实用意义。还可以用模式识别法去研究微量元素与中药的解表、清热、理气、理血等药性的关系,指导合理用药和配伍,深入研究中药与元素数据的关系,可以发现其中许多意想不到的科学规律。
"数据"所参考的1 036条文献,全是公开发表的论文和专著,是中国科研人员使用34种先进的分析测试方法所得的分析测试数据,是研究课题的"数据",有高度的可靠性。对中药进行"解剖"测试,不但测定其"全身"中的元素,还测定其不同"器官"中的元素含量,如人参,既测定全参,又测定人参子、人参叶、人参皮、人参花、人参芦、人参茎、人参果、人参须等8个不同部位的元素含量,用元素功能指导临床用药很有帮助,甚至有些可用替代药,而且用中药治疗的阴虚、阳虚? 相似文献
98.
建立高效液相色谱同时测定黄酒中安赛蜜、苯甲酸、山梨酸和糖精钠4种非法食品添加剂的方法。黄酒中的待测物质经提取后,采用C18柱分离,以甲醇–乙酸铵溶液为流动相进行洗脱,在波长230 nm处用高效液相色谱–二极管阵列检测器进行测定。安赛蜜、苯甲酸、山梨酸和糖精钠的质量浓度在0.5~200.0μg/mL范围内与其色谱峰面积的线性关系良好(r0.999 7),检出限为0.29~0.74μg/L。在0.5,1.0,2.5,5.0,7.5 mg添加水平时的平均回收率在95.6%~104.0%范围内,测定结果的相对标准偏差为0.3%~1.5%(n=6)。该方法操作简便,分离效果好,灵敏度高,结果稳定可靠,适合于黄酒中安赛蜜、苯甲酸、山梨酸和糖精钠的同时测定。 相似文献
99.
A concept for taking a sample from a polymer melt stream plus the direct processing of this melt to specimen is presented. Therefore, a melt sampling and direct injection molding (MSIM) device was developed. Process parameters were studied and the set-up was implemented successfully. Using the MSIM device, different thermoplastics were processed and provided specimen characterized. The mechanical material properties from samples of the MSIM process show a good consistency compared with data from conventional processes. The MSIM device can be used in production processes for quality control, e.g. color or mechanical properties, as well as in the field of research and development to reduce development cycles. 相似文献
100.
Kang Du Jingyi Yang Li Yang Zhengtao Wang Rui Wang Yanhong Shi 《Journal of separation science》2020,43(13):2558-2570
Clarification of the quality and biological effect equivalence of traditional Chinese medicines containing multi‐origin species is essential to improve their current quality standards, and also is the core problem to clarify the origins of single herbs with multi‐species in Chinese formulas that will guarantee their clinical application. Huangqin decoction is the typical one of multi‐origin formulas frequently used in traditional Chinese medicine and Kampo medicine. An ultra high performance liquid chromatography with electrospray ionization–tandem mass spectrometry was developed for chemical profiling and marker quantification of Huangqin decoction prepared with two different original types of peony root, white and red peony root. Forty‐seven main peaks in chemical profiling of Huangqin decoction prepared with white and red peony root were identified: nine were from peony root, 20 from baical skullcap root, 17 from licorice root, and one from jujubae fruit. The markers characteristics of the respective types of peony root in Huangqin decoction differ from that in single herbs, especially in terms of monoterpenoids and hydrolysable tannins. Subsequently, 17 representative markers in Huangqin decoction prepared with three types of peony root and their chemical characteristics and content distribution were carried out. 相似文献