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Biomedical subjects

B Selmeczi

Publications and source records attributed to B Selmeczi.

At least 37 records · Page 2Linked to original sources
PubMed1990

[Biopharmaceutical study of aminophenazone-containing suppositories. 2. Results of in vitro drug release and in vivo drug absorption].

Ten kinds of surface active ingredients of Th. Goldschmidt AG. (Essen-FRG) in concentrations of 5% were mixed with Witepsol W 35 and Massa Estarinum 299 suppository masses of Hüls-Troisdorf AG. Werk (Witten-FRG) which are official in Hungary. According to the authors the above tensides, which have been used advantageously first of all in ointments, creams and cosmetic preparations, can also be applied in rectal preparations. In the publication of two parts it has been established that these ingredients influence physical parameters of suppositories beneficially. They always increase significantly in vitro diffusion values and in some cases with order of magnitude. Massa Estarinum 299 containing 5% of Emulgator BTO proved to be the best in case of chosen suppositories containing aminophenazone. Correlation between in vitro and in vivo investigations has shown the importance of correct selection of base and ingredient materials in biopharmaceutical work.

Aminopyrine↗
PubMed1990

[Deformation phenomena occurring during compression. II].

Compressed forms were prepared from sodium chloride of given granule size with mildly concave punches applying 4, 12 and 20 kN pressing force. Pressing was regulated in order to get maximum pressing force effect for 0.1 s, 30 s and 60 s. Textures of side of compressed forms as well as edge and middle of surface of compressed forms were investigated by scanning electron microscope. Photos made with different enlargement have proved that secondary structural changes have begun (colour changes, new crystals have come to being etc.) on side stronger but also well observable on surface of compressed forms which in function of pressing force and that of time of pressing force effect have increased and grown considerably.

Microscopy, Electron, Scanning↗
PubMed1990

[Deformation phenomena occurring during compression. I].

Tablets were prepared from sodium chloride of given granule size with 4, 12 and 20 kN pressing force. Pressing was regulated in order to get maximum pressing force effect for 0.1 s, 30 s and 60 s. With the intention of studying deformation changes texture investigation of breaking surface of tablets was carried out by scanning electron microscope. Investigation results documented with photos of different enlargement showed that both pressing force and pressing force effect influenced deformation changes and also structure of tablets. Increase of time of pressing force effect resulted in perfection of deformation changes.

Microscopy, Electron, Scanning↗
PubMed1989

[Effect of gelatin solution on parameters of tablets containing well-compressible active principles].

Theobromine tablets have been prepared by wet granulation using gelatin solutions of various concentrations. It has been established that film formed from 2 per cent gelatin solution does not assure sufficient binding force. Lamella forming tendency could be observed on tablets. Furthermore, it has been ascertained that tablets proper in respects of both physical parameters and active principle release can be prepared with 5 per cent gelatin solution. It seems to be unnecessary to use 10 per cent gelatin solution. Behaviour of gelatin solutions at compression of starch and their role in active principle release have been discussed. Attention has been drawn to loss of biological value because of the "aging" of the gelatin film.

Gelatin↗
PubMed1989

[Application of beta-cyclodextrin during direct pressing of tablets].

In case of tablets prepared by direct procedure the compressibility of beta-cyclodextrin has been studied. It has been established that beta-cyclodextrin--because of its very good flowing behaviour--can successfully be applied as ingredient in direct pressing. When hardness of tablets has to be increased 20% Avicel pH 101 (VN) has been recommended. By comparative test of 1:1 mol physical mixture of chloramphenicol-beta-cyclodextrin and the granulated product it has been ascertained that method of preparation of products, behaviour of applied solid binding materials and degree of applied pressing force decisively influence the compressibility of products. Furthermore, it has been found that application of beta-cyclodextrin influences advantageously the dissolution rate of active principle from tablets.

Cyclodextrins↗
PubMed1989

Formulation of Polyethylene Glycol ointment bases suitable for tropical and subtropical climates. II.

Attention has been focused on the suitability of PEG ointment bases in tropical and subtropical regions. Penetrometer studies were carried out at 33, 37 and 50 degrees C respectively. Penetrometer experiments indicate that the type and amount of PEG will greatly affect the penentration time, and a large number of selected PEGs showed softening in the second month. Rotovisco experiments were conducted at 35 and 45 degrees C. Experiments conducted by Rotovisco at 35 degrees C indicate that PEG bases exhibit plastic flow and rheopexy, and there is an increase in yield values during the twelve months. Experiments worked out by Rotovisco at 45 degrees C reflected that an increase in temperature resulted in a decrease in rheopexy, viscosity, area of histeresis loop and yield values. Results obtained by the two methods demonstrate that PEG 4000 in the presence of equal amounts of PEG 400 has a good texture and might be a suitable ointment base for tropical and subtropical areas.

Climate↗
PubMed1988

[The liberation of phenylbutazone from tablets].

The liberation of phenylbutazone from tablets prepared by wet granulation was examined. It was found that the solution process can be described by the equation c = cs (l-e-K.t alpha). The influence of the binder concentration and the disintegrant on the liberation rate was also studied. The increase of the Klucel MF concentration accelerated the liberation of the agents. Among the disintegrants Polyplasdone XL and cyclodextrin block polymer turned out to be very good.

Drug Compounding↗
PubMed1988

[Direct compression nitrazepam tablets].

Tablets of nitrazepam were made by direct compression. The influence of different dry binders and other adjuvants on the physical parameters of the tablets and their texture (scanning electron microscope: SEM) were examined. Changes in the physical parameter can be explanded if the texture is known.

Drug Compounding↗
PubMed1987

[The polymorphism of drugs in powders and tablets. 1. The preparation and characterization of polymorphic modifications of phenobarbital].

The characterisation of three phenobarbital modifications by thermic examination procedures (DSC, DTA) is being described. Modification I was obtained by thermic treatment of the brands (modification II) from Hungary and the GDR. The spray product prepared, consisting of very fine hollow spheres, was identified as modification III. Besides the particle size distribution the form of the particle was determined by scanning electron microscopy (REM). The best results regarding saturation solubility and speed of dissolution were found for the spray product.

Chemistry, Pharmaceutical↗
PubMed1987

[The polymorphism of drugs in powders and tablets. 4. The effect of the polymorphism of drugs on the physical properties and drug release of phenobarbital tablets].

Four products of phenobarbital (I, II1, II2, III) are manufactured into tablets with the dry binders Avicel PH 101 or Heweten 40 using different pressures by direct tabletting. The physical properties of the resulting tablets are different according to the modification of phenobarbital, the binders used and the pressure during tabletting. The dissolution behaviour of the drug may be changed by the different technological and physical parameters.

Chemical Phenomena↗