Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters











Database
Language
Publication year range
1.
Pharmeur Sci Notes ; 2009(1): 1-4, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19275866

ABSTRACT

Quality of homoeopathic mother tinctures is assured by the definition of the starting material, the manufacturing process and the analytical characteristics described in the monograph. Traditionally analytical characterisation of the mother tincture comprises appearance, odour, identity, density and dry residue. According to annex I of directive 2001/83/EC an assay is only performed in case of a health hazard due to toxic compounds. The concept of marker substances as usually used in phytotherapy cannot be transferred to mother tinctures without research effort. For example the marker substances echinacoside, apigenin-7-glucoside and rosmarinic acid found in dried underground parts of Echinacea pallida Nutt., dried flower heads of Matricaria recutita L. and dried herb of Pulmonaria officinalis L. cannot be found in homoeopathic mother tinctures prepared from fresh material thereof.


Subject(s)
Materia Medica/analysis , Chromatography, Liquid , Chromatography, Thin Layer , Echinacea/chemistry , Flavonoids/analysis , Germany , Homeopathy/standards , Matricaria/chemistry , Pharmaceutical Solutions , Pharmacopoeias, Homeopathic as Topic , Phenols/analysis , Plant Preparations/analysis , Polyphenols , Pulmonaria/chemistry , Reference Standards , Solutions
3.
Pharm Dev Technol ; 4(3): 359-67, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10434281

ABSTRACT

The purpose of this work was to develop an instrumented upper punch to measure the adhesion force which occurs when the punch detaches itself from the upper surface of the tablet after compression. A specially designed adhesion force sensor instrumented with semiconductor strain gauges was inserted into an upper punch with a 25-mm punch face diameter suitable for a Korsch EK II eccentric press. Sorbitol, microencapsulated acetylsalicylic acid (ASA), and a formulation of a new active ingredient resulted in characteristic pull-off signals, providing a quantitative measure of the adhesion force. With "sticking-free" substances such as microcrystalline cellulose, tension signals could not be obtained; only Starch 1500 showed small adhesion force signals that indicated a sticking tendency. The compression force had a specific influence on the extent of the adhesion force; increasing the compression force caused an increase (sorbitol) or a decrease (ASA) of the adhesion force signals due to the plastic and elastic behavior of the substances. Depending on running time, ASA showed an increase in the adhesion force, reaching a plateau after 150 tablets. The addition of lubricants such as magnesium stearate resulted in smaller adhesion forces. The instrumented upper punch is a new helpful tool for the quantification of sticking and a valuable instrument in the development of formulations.


Subject(s)
Drug Compounding/methods , Tablets , Adhesiveness , Calibration , Excipients , Pharmaceutic Aids/administration & dosage , Pharmaceutic Aids/chemistry , Signal Transduction , Sorbitol/administration & dosage , Sorbitol/chemistry , Starch
4.
Pharm Dev Technol ; 4(3): 369-75, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10434282

ABSTRACT

The purpose of this study was to investigate the influence of engravings on the sticking of tablets. Therefore, an instrumented upper punch capable of measuring the pull-off force, which occurs when the punch detaches itself from the upper surface of a tablet, was equipped with small cones of different angles between the punch face and the cones' lateral face. The cones could be screwed into a threaded hole at the center of the punch face. The adhesion forces of two formulations known to stick to engravings during production increased with a greater steepness of the cones' lateral face. With microencapsulated acetylsalicylic acid, no quantitative differences could be found between the adhesion forces obtained with plain and modified punch faces, indicating that the sticking behavior of the substance was not affected by shear forces. Starch 1500 showed higher adhesion force signals in comparison to those obtained with a plain punch face. Microcrystalline cellulose, which gave no adhesion force signals with a plain punch face and did not stick to the cones, showed distinct pull-off signals. The instrumented upper punch equipped with shear cones is a valuable instrument for detecting the adhesion caused by engravings and is therefore a helpful tool for tablet formulation development and the design optimization of tablet identification.


Subject(s)
Tablets , Adhesiveness , Cellulose , Drug Compounding/methods , Excipients , Lactose , Online Systems , Pressure , Rheology , Starch , Surface Properties
SELECTION OF CITATIONS
SEARCH DETAIL