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排序方式: 共有334条查询结果,搜索用时 15 毫秒
331.
Zhiyong Zhang Xiaoyang Zhang Shunan Li Yun Chen Zheng Li Yunlan Lian Wenlong Li 《Electrophoresis》2023,44(9-10):793-806
In this study, the capillary electrophoresis-photodiode array detector was employed for the analysis of four iridoid compounds in Gentiana macrophylla Radix (RGM), and the method was optimized based on the concept of analytical quality by design (AQbD). The peak areas relative standard deviation (n = 3) and resolution of the four analytes were selected as critical method attributes. Fractional factorial design test combined with Pareto analysis were employed to screen critical method parameters (buffer concentration, pH, sodium dodecyl sulfate [SDS] micelle concentration, temperature, and voltage). Subsequently, three main factors (buffer concentration, buffer pH, and SDS concentration) were selected by central composite design test for constructing the design space. The optimal separation conditions as follows: capillary column (50.2 cm × 50 µm, detection length 40 cm). Working background electrolyte consisted of 51 mmol/L borax solution (pH = 9.47) and 40 mmol/L SDS. The samples were injected by pressure (5 s at 0.5 psi) and the detection was performed at 254 nm. Applied voltage was 20 kV and column temperature was 23°C. The developed method is rapid and reliable for the quantitative analysis of four iridoid compounds in RGM, providing a reference for the application of AQbD concept in the analysis of natural products. 相似文献
332.
Zhiyong Zhang Nan Hao Long Wang Shunan Li Xinhao Yan Xuting Guo Yunlan Lian Wenlong Li 《Electrophoresis》2023,44(13-14):1068-1079
The aim of this study was to establish a rapid quality assessment method for Gentianae Macrophyllae Radix (RGM) using near-infrared (NIR) spectra combined with chemometric analysis. The NIR spectra were acquired using an integrating sphere diffuse reflectance module, using air as the reference. Capillary electrophoresis (CE) analyses were performed on a model P/ACE MDQ Plus system. Partial least squares-discriminant analysis qualitative model was developed to distinguish different species of RGM samples, and the prediction accuracy for all samples was 91%. The CE response values at each retention time were predicted by building a partial least squares regression (PLSR) calibration model with the CE data set as the Y matrix and the NIR spectra data set as the X matrix. The converted CE fingerprints basically match the real ones, and the six main peaks can be accurately predicted. Transforming NIR spectra fingerprints into the form of CE fingerprints increases its interpretability and more intuitively demonstrates the components that cause diversity among samples of different species and origins. Loganic acid, gentiopicroside, and roburic acid were considered quality indicators of RGM and calibration models were built using PLSR algorithm. The developed models gave root mean square error of prediction of 0.2592% for loganic acid, 0.5341% for gentiopicroside, and 0.0846% for roburic acid. The overall results demonstrate that the rapid quality assessment system can be used for quality control of RGM. 相似文献
333.
《Arabian Journal of Chemistry》2023,16(5):104590
Scutellariae Radix, the root of Scutellaria baicalensis Georgi, is widely applied in China for the treatment of fever, ulcer, bronchitis, hepatitis and inflammatory symptoms. Sctuellariae Amoenae Radix, the root of Scutellaria amoena C.H. Wright, is often prescribed as the substitute for Scutellariae Radix. Up to now, no attempt has been made to unveil and compare the localization of phytochemicals in Scutellariae Radix and its succedaneum. This investigation succeeded to look into the differential distribution of natural compounds in Scutellariae Radix and Scutellariae Amoenae Radix using microscopic mass spectrometry imaging. Compounds presenting different distribution modes in two kinds of roots were sorted out, then a quick method for the differentiation between Scutellariae Radix and Scutellariae Amoenae Radix was established. Accumulation sites of baicalein, baicalin, wogonin and wogonoside in Scutellariae Radix were also uncovered using microscopic mass spectrometry imaging. Moreover, the application of matrix assisted laser desorption ionization-quadrupole-time of flight mass spectrometry allowed the on-tissue dissociation of major flavonoids. Overall, the utilization of microscopic mass spectrometry imaging and matrix assisted laser desorption ionization-quadrupole-time of flight mass spectrometry provided a novel perspective for the discovery of natural compounds within medicinal plants. 相似文献
334.
Yanhong Ma Bixing Gao Jingliang Qi Yan Gou Zhi Li Yingxin Chen Min Li Juan Zhou Lian Zhong Xiaoyang Cai 《Biomedical chromatography : BMC》2023,37(1):e5526
Because of the immense difficulty in identifying Cyathulae Capitatae Radix adulteration in Cyathulae Radix, this research aims at fortifying the quality control of Cyathulae Radix and its decoction pieces to guarantee the effectiveness and safety of its clinical use in terms of source material. A method was devised to identify Cyathulae Capitatae Radix adulteration in Cyathulae Radix and its decoction pieces. This research takes achybidensaponin I, that is, the characteristic component of Cyathulae Capitatae Radix, as reference substance and adopts HPLC for detection. The results revealed that, among all samples collected, no trace of achybidensaponin I was found in the 21 batches of Cyathulae Radix, whereas achybidensaponin I was found in all the 14 batches of Cyathulae Capitatae Radix. The research sets 5% as the adulteration limit, that is, 1.45 mg/g Cyathulae Capitatae Radix was detected in 57.14% of the 49 batches of market samples collected and the ratio was 51.02% in the case of 5% adulteration limit. The method is not only precise and reliable but can also be used as a supplement for provisions regarding quality control of Cyathulae Radix and its decoction pieces in Pharmacopoeia of the People's Republic of China, to effectively crack down on Cyathulae Capitatae Radix adulteration in the market. 相似文献