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Jensen AG Ndjoko K Wolfender JL Hostettmann K Camponovo F Soldati F 《Phytochemical analysis : PCA》2002,13(1):31-38
In order to evaluate the composition of active constituents in phytopharmaceutical preparations, valid analytical methods are required. For the determination of the active terpene constituents of Ginkgo biloba (the ginkgolides and bilobalide), a liquid chromatography-mass spectrometry (LC-MS) method has been developed using atmospheric pressure chemical ionisation (APCI) in the negative ion mode. This detection mode was found to be much more sensitive and selective compared to UV; indeed the ginkgo terpene trilactones lack strong UV chromophores and flavonoids interfere with their UV detection. LC-APCI/MS detection allowed a considerable reduction in analysis time when compared to LC-UV, because LC resolution was only needed between the pair of isomers ginkgolide B and ginkgolide J. All compounds were selectively detected by single ion monitoring of their specific deprotonated molecules [M-H]-. The samples were directly injected without pre-purification, and a fast gradient was applied, reducing the total time of analysis to 14 min. With this method, the ginkgo terpene trilactones were detected on-line in the picogram range. Several commercial ginkgo preparations on the Swiss market were analysed, and the ginkgolide and bilobalide contents were evaluated using the method described. 相似文献
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Pereira de Souza T Martínez-Pacheco R Gómez-Amoza JL Petrovick PR 《AAPS PharmSciTech》2007,8(2):E54-E60
The aim of this study was to investigate the feasibility of using Eudragit E as a granulating agent for a spray-dried extract
fromPhyllanthus niruri to obtain tablets containing a high dose of this product. The granules were developed by wet granulation and contained 2.5%,
5.0%, and 10.0% Eudragit E in the final product concentration. The tablets were produced on a single-punch tablet press by
direct compression of granules using 0.5% magnesium stearate as a lubricant. The tablets were elaborated following a 2×3 factorial
design, where Eudragit E concentration and compression force were the in-dependent variables, and tensile strength and the
extract release of the tablets were the dependent variables. All granules showed better technological properties than the
spray-dried extract, including less moisture sorption. The characteristics of the granules were directly dependent on the
proportion of Eudragit E in the formulation. In general, all tablets showed high mechanical resistance with less than 1% friability,
less moisture sorption, and a slower extract release profile. The Eudragit E concentration and compression force of the tablets
significantly influenced both dependent variables studied. In conclusion, Eudragit E was efficient as a granulating agent
for the spray-dried extract, but additional studies are needed to further optimize the formuations in order to achieve less
water sorption and improve the release of the extract from the tablets.
Published: April 27, 2007 相似文献
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