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21.
Summary A reversed-phase liquid chromatographic method with sodium dodecylsulphate-n-propanolwater as mobile phase has been used to separate and determine six water-soluble vitamins in twelve minutes. The analytical
characteristics linear range, sensitivity, detection limits, and precision were evaluated. The lowest detection limits were
those of nicotinic acid (not usually present in pharmaceutical products), 0.7 mgL−1, nicotinamide, 1.3 mg L−1, and pyridoxine, 1.4 mg L−1. When the method was applied to the determination of the vitamins in pharmaceutical samples the values found agreed with
those on the labels. 相似文献
22.
Isolation and purification of honokiol and magnolol from cortex Magnoliae officinalis by high-speed counter-current chromatography 总被引:5,自引:0,他引:5
High-speed counter-current chromatography was used to isolate and purify honokiol and magnolol from cortex Magnoliae Officinalis (Magnolia officinalis Rehd. et Wils.), a plant used in the traditional Chinese medicine. A crude sample, 150 mg, was successfully separated with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.4:1:0.4, v/v), and the fractions were analyzed by high-performance liquid chromatography. The separation produced 80 and 45 mg of honokiol and magnolol with purities of 99.2 and 98.2%, respectively, in 2.5 h. 相似文献
23.
High Performance Liquid Chromatographic Analysis of Pharmaceuticals Using Oil-In-Water Microemulsion Eluent and Monolithic Column 总被引:1,自引:0,他引:1
Novel and efficient separations of pharmaceutical substances were achieved using oil-in-water microemulsion eluent and a conventional
C18 packing with a flow rate of 1 mL/min−1. Attempts to decrease analysis time was limited due to the high viscosity of the microemulsion which generated relatively
high back-pressures. Monolithic columns gave 3-fold lower back-pressures and allowed flow rates of 4 mL/min−1. with the same microemulsion mobile phase which permitted rapid separations to be achieved. Separation of a test-mix of paraben
preservatives was achieved in both isocratic and gradient mode in less than 1 min. The monolith-microemulsion combination
was applied to rapidly quantitatively analyse two formulated products with excellent linearity, accuracy and repeatability.
Quantitative analysis times were under 90 seconds. Successful quantitation of both nicotine lozenges and naprosyn tablets
was performed using this approach. 相似文献
24.
René Grouls Wim van de Laar Henk M. J. Goldschmidt Frits G. van Merode 《Accreditation and quality assurance》2004,10(1-2):41-46
Many medical professionals are involved in patient care processes. For pharmaceutical care this results in many information transfer moments. To provide optimal care, communication and information the transfer should be conducted in a timely manner, fully transparent, complete and relevant. The TRANSFORM project is directed towards the development of a reference information model of the pharmaceutical care chain with the aim to improve the availability (time, place, completeness) and access of pharmaceutical information regarding patients, thereby resulting in continuity and quality of pharmaceutical care, reduction in medical errors and improvement in patient safety through the design of a safer healthcare system. TRANSFORM leads to improved insight into the processes and data transfer points in the pharmaceutical chain of care. Focussed on laboratory medicine and pharmacy, the implementation of the integration of laboratory test and pharmacy information may result in major improvements in drug therapy monitoring and guidance (i.e. drug impact monitoring). Because of the overwhelming amount of data generated by this integration of drugs, drug effects and laboratory test results, an online decision support system is warranted.Presented at the 9th Conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium.The following paper may appear at first sight not to be specifically within the realm of ACQUAL. It has been accepted for publication anyway as it is about reliable handling of data, incl. measurement results, which lead to important decisions (in this case related to a patient). The reliability of handling (a large amount of) measurement results towards a basis for important decisions, is a very important feature of the use of such results.Paul De Bièvre, Editor in Chief 相似文献
25.
化合物库的组合技巧和组合合成 总被引:2,自引:0,他引:2
从化合物库的组合技巧和组合合成方法两个方面探讨了组合化学及其在药物开发中的应用。 相似文献
26.
The m6A‐RNA modification is a dynamic and reversible process, which has emerged as a new RNA code for the regulation of gene expression. The functional network of methyltransferases (writers), demethylases (erasers), and binding proteins (readers) modulate the level of m6A modification. Dysfunction of RNA methylation has been associated with various fundamental biological processes and human diseases. Herein, we briefly introduce an understanding‐enabled manipulation on m6A‐RNA modification with an emphasis on the use of small‐molecule intervention. 相似文献
27.
The use of open-access mass spectrometry to monitor synthetic chemistry reactions, and also the integrity and purity of new chemical entities, has been a part of the medicinal chemist's tool-box for more than 5 years. Originally in our group at Wyeth Research there were two open-access methods available to the chemists, flow injection analysis (FIA) and liquid chromatography/mass spectrometry (LC/MS). The FIA method was approximately 3 min long, while the LC/MS method was approximately 20 min long (including an 8 min gradient). Within the first 2 years, the total number of open-access analyses increased by approximately 125%. It is interesting, however, that the number of LC/MS analyses increased by more than 285%. This is attributed to the fact that the chemists began using the LC/MS data to monitor reactions and also to check final product integrity and purity. In addition, the number of chemists performing parallel synthesis reactions has increased; thus, individual chemists can produce sample sets of up to 100 vials. This paper describes the implementation of new methodology, which accommodates the need for much faster run times and also the ability to acquire alternating positive and negative ion spectra within the same run. In addition, the instrument has been configured to e-mail the resulting processed data report to the submitting chemist. Several methods have been developed, including structure elucidation using in-source collision-induced dissociation (CID) and night-time analysis. The LC/MS methods for this system are described herein and are applicable to both industrial and academic synthetic chemistry optimization efforts. 相似文献
28.
B. Venkateswara Reddy K. V. N. Suresh Reddy J. Sreeramulu G. V. Kanumula 《Chromatographia》2007,66(1-2):111-114
A rapid, specific reversed phase HPLC method has been developed for simultaneous determination of olanzapine and fluoxetine
in their formulations. Chromatographic separation of these two pharmaceuticals was carried out on an Inertsil C18 reversed phase column (150 mm × 4.6 mm, 5 μm) with a 40:30:30 (v/v/v) mixture of 9.5 mM sodium dihydrogen phosphate (pH adjusted to 6.8 ± 0.1 with triethylamine), acetonitrile and methanol as
mobile phase. The flow rate 1.2 mL min−1 and the analytes are monitored at 225 nm. Paroxetine was used as internal standard. The assay results were linear from 25
to 75 μg mL−1 for olanzapine (r
2 ≥ 0.995) and 100–300 μg mL−1 for fluoxetine (r
2 ≥ 0.995), showed intra- and inter-day precision less than 1.0%, and accuracy of 97.7–99.1% and 97.9–99.0%. LOQ was 0.005
and 0.001 μg mL−1 for olanzapine and fluoxetine, respectively. Separation was complete in less than 10 min. Validation of the method showed
it to be robust, precise, accurate and linear over the range of analysis. 相似文献
29.
C. C. Camarasu 《Chromatographia》2002,56(1):S131-S135
Summary A sensitive headspace SPME method for the extraction of residual solvents from pharmaceutical products has been developed
and optimized. It was found that minimizing sample and headspace volume has a beneficial effect on extraction efficiency.
At the same time the method reproducibility was seriously affected by reducing sample and headspace volume. The added air
volume was not found to have any significant influence on method sensitivity. The method showed reproducibilities of less
than 10% and detection limits as low as 1 ppb for benzene and dichloromethane. The headspace SPME method is around 1000 times
more sensitive than static headspace. The optimized parameters were headspace volume 1.5 mL, sample volume 10 μL, and extraction
time 30 min. The method was successfully applied to the identification of unknown residual solvents in three different proprietary
active drug substances and was successfully applied to the confirmation of the presence of benzene in a proprietary drug substance.
Presented at Balaton Symposium '01 on High-Performance Separation Methods, Siófok, Hungary, September 2–4, 2001 相似文献
30.