In recent years, more and more researchers focus on the selectivity of RP-HPLC columns. Among these columns, C18 column is the most commonly used the column. Yet even the same filler can not give us the same separation effect with the columns of different brands and different types, therefore, it is important to choose the suitable HPLC column for carrying out an experiment. After study in recent years, some column classification, selection methods (e.g.: column parameter method, F value method) have been achieved and contributed to the finding of suitable columns and reducing the blindness of column selection. This paper summarizes the advantages of these methods and their limitations in the application process, and gives some advice and expectations to pharmaceutical analysis works based on the works of other researchers.
Chromatography, High Pressure Liquid ; methods ; Chromatography, Reverse-Phase ; instrumentation ; methods ; Drug Contamination ; Pharmaceutical Preparations ; isolation & purification

Artificial neural network (ANN) is a multi-objective optimization method that needs mathematic and statistic knowledge which restricts its application in the pharmaceutical research area. An artificial neural network parameters optimization software (ANNPOS) programmed by the Visual Basic language was developed to overcome this shortcoming. In the design of a sustained release formulation, the suitable parameters of ANN were estimated by the ANNPOS. And then the Matlab 5.0 Neural Network Toolbox was used to determine the optimal formulation. It showed that the ANNPOS reduced the complexity and difficulty in the ANN's application.
Chemistry, Pharmaceutical ; Delayed-Action Preparations ; Drug Design ; Ligusticum ; chemistry ; Neural Networks (Computer) ; Pyrazines ; administration & dosage ; isolation & purification ; Software ; Tablets

OBJECTIVETaking alkaloids and iridoid as the study, relationships of quantitative molecular structure and transmission rate on UF membrane were developed initially at exploring the mechanism of UF in Chinese herb decoction and to lay a foundation for the optimal design of membrane technology in the production of Chinese drugs preparation.

METHODThe transmission rate of eight alkaloids and iridoid compounds in three UF membranes was determined, and quantitative structure-property relationships between quantitative molecular structure and transmission rate were developed by the data mining method of PLS or SVM.

RESULTQuantitative structure-property relationship models of three membranes were developed by the data mining method of PLS or SVM, correlation coefficients were all greater than 0.9. The parameters in the models included LUMO, AlogP, CMR, K&H2, K&H3.

CONCLUSIONThe relationship of UF transmission rate of these eight compounds and their molecular weight are not simply linearly dependent, the main factors which affect the UF transmission rate are capacity of gain or loss electron, hydrophilicity or hydrophobic and compound spatial structure.

Alkaloids ; chemistry ; isolation & purification ; pharmacology ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; Iridoids ; chemistry ; isolation & purification ; pharmacology ; Molecular Weight ; Permeability ; Pharmaceutical Preparations ; chemistry ; isolation & purification ; Quantitative Structure-Activity Relationship ; Ultrafiltration ; methods

This paper reviews the lastest progress on oral prolonged-release preparation of traditional Chinese medicine. Four materials, include component, effective parts, single drug, and compound drugs of traditiong Chinese medicine, have been used to produce oral prolonged-release preparation. The main contents are study of preparation and evaluation of in vitro release. There are also some research works on integrative evaluation, pharmacokinetics and pharmacological activity of the prolonged-release preparation. It believes that the study on oral prolonged-release preparation of traditional Chinese medicine will have good prospect.
Animals ; Delayed-Action Preparations ; pharmacokinetics ; toxicity ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacokinetics ; toxicity ; Plants, Medicinal ; chemistry ; Technology, Pharmaceutical ; methods

Microparticle preparation, a new drug delivery system based on microencapsulation technique, includes micro-spheres and microcapsules. Recently, this new drug delivery system has been applied in developing new dosage forms for the traditional Chinese medicine (TCM). TCM microparticles can perform several sound characteristics and functions which are currently unavailable in TCM preparations, such as controlled release, effect of targeting, increasing bioavailability or low toxicity. This makes it possible that TCM may exert much higher therapeutic efficacy and show lower side-effects as well. Although the studies on TCM microparticles are still in the beginning stage, microparticle preparation of TCM has given rise to comprehensive attention and will have a wonderful prospect. The progress in this field is reviewed in this article.
Animals ; Biological Availability ; Delayed-Action Preparations ; Drug Delivery Systems ; methods ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacokinetics ; Humans ; Microspheres ; Particle Size ; Plants, Medicinal ; chemistry ; Technology, Pharmaceutical ; methods

SCHWABE Company in German is the first and largest manufacturer of Ginkgo biloba preparation. The company not only has leading technology in this field, but also protects its own market effectively through the high quality of patent drafting and exactly patent layout. Based on multi-angle analysis for patent portfolio of G. biloba preparation at application time, legal status, globally layout, Chinese layout, the article provides technical reference of research and development of G. biloba, also provides valuable experience of traditonal Chinese medicine patent portfolio layout for Chinese enterprises.
Drug Industry ; economics ; legislation & jurisprudence ; trends ; Ginkgo biloba ; chemistry ; Humans ; Patents as Topic ; legislation & jurisprudence ; Phytotherapy ; economics ; trends ; Plant Preparations ; isolation & purification ; Technology, Pharmaceutical ; economics ; trends

Pellets are multiple-unit drug delivery system, which have good fluidity, release stability and uniformity. With preparation techniques and excipient materials gradually established, pellets play an important part in the development of sustained/controlled release drug delivery system. The recent advances in pellets including the release mechanism, preparation methods, excipients and the characteristics in vivo for the sustained/controlled release pellets in traditional Chinese medicine (TCM) were reviewed in order to provide the strategies and rational methods for further investigations and applications.
Animals ; Capsules ; Delayed-Action Preparations ; chemistry ; Drug Delivery Systems ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; isolation & purification ; Humans ; Microspheres ; Plants, Medicinal ; chemistry ; Polyethylene Glycols ; chemistry ; Technology, Pharmaceutical ; methods

OBJECTIVE: To develop a specific, sensitive, reproducible SPE-HPLC method for the determination of 37 drugs in whole blood. METHODS: With the doxapram as internal standard, Oasis column was used to extract drugs from whole blood. Two kinds of mobile phases were used in this study. Separations were achieved by a LiChrospher 100 RP-C18 (250 mm x 4.0 mm x 5 microm) column kept at 50 degrees C, the DAD detector was set at 230 nm and 250 nm. RESULTS: The limit of detection were 1-30 ng/mL. The method showed excellent linearity and the linear correlation coefficient was > or =0.997 98. The relative standard deviation for between-day and within-day assay were <10%. CONCLUSION The method is effective, simple, reliable and has been used in real cases.
Chromatography, High Pressure Liquid/methods* ; Doxapram/isolation & purification* ; Doxepin/isolation & purification* ; Estazolam/isolation & purification* ; Forensic Medicine ; Humans ; Morphine/isolation & purification* ; Papaverine/isolation & purification* ; Pharmaceutical Preparations/isolation & purification* ; Prazosin/isolation & purification* ; Procaine/isolation & purification* ; Reproducibility of Results ; Sensitivity and Specificity ; Solid Phase Extraction/methods* ; Solvents/chemistry*

The purpose of this study is to investigate the applicability of a natural swelling matrix derived from boat-fruited sterculia seed (SMS) as the propellant of osmotic pump tablets. The sugar components, static swelling, water uptake and viscosity of SMS were determined and compared with that of polythylene oxide (WSR-N10 and WSR-303). Both ribavirin and glipizide were used as water-soluble and water-insoluble model drugs. Then, the monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide were prepared using SMS as the osmotically active substance and propellant. SMS was mainly composed of rhamnose, arabinose, xylose and galactose and exhibited relatively high swelling ability. The area of the disintegrated matrix tablet was 20.1 times as that at initial after swelling for 600 s. SMS swelled rapidly and was fully swelled (0.5%) in aqueous solution with relative low viscosity (3.66 +/- 0.03) mPa x s at 25 degrees C. The monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide using SMS as propellant exhibited typical drug release features of osmotic pumps. In conclusion, the swelling matrix derived from boat-fruited sterculia seed, with low viscosity and high swelling, is a potential propellant in the application of osmotic pump tablets.
Arabinose ; chemistry ; isolation & purification ; Chemistry, Pharmaceutical ; Delayed-Action Preparations ; Drug Carriers ; Galactose ; chemistry ; isolation & purification ; Glipizide ; administration & dosage ; chemistry ; Osmosis ; Plants, Medicinal ; chemistry ; Rhamnose ; chemistry ; isolation & purification ; Ribavirin ; administration & dosage ; chemistry ; Seeds ; chemistry ; Solubility ; Sterculiaceae ; chemistry ; Tablets ; Technology, Pharmaceutical ; methods ; Viscosity ; Water ; Xylose ; chemistry ; isolation & purification

Bioactive natural products of novel structural types play a highly significant role in the drug discovery and development process. Of the 1,031 new chemical entities covering all diseases in the years 1981-2002, 48% were natural product mimics, 5% were the direct utility of natural products as sources of novel structures. Up to now, the main challenges are more efficient and rapid processes for discovery and isolation of bioactive natural products of novel structural types. Therefore, new strategies and ideas for chemical study on bioactive natural products of novel structural types should be applied. In order to discover a large number of bioactive natural products of novel structural types from naturally occurring sources and elucidate the intrinsic value of natural products as leads to new structures with different activities, new, more efficient and rapid processes for study on natural products will be established by use of modern chromatographies, techniques on line identification of natural products and screening methods based on molecular targets.
Biological Products ; chemistry ; isolation & purification ; Drug Design ; Drug Evaluation, Preclinical ; Humans ; Pharmaceutical Preparations ; chemical synthesis ; isolation & purification ; Pharmacognosy ; methods ; Plant Extracts ; pharmacology ; Plants, Medicinal ; chemistry ; classification ; Structure-Activity Relationship