PubMed · 5736180
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
F Storti. [Sorbitol].. https://pubmed.ncbi.nlm.nih.gov/5736180/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Surfaces of pharmaceutical powders have been assessed using contact angle, inverse phase gas chromatography (IGC) and triboelectric (electrostatic) charging techniques. The suitability of the Dynamic Angle Tester (DAT), an instrument based on the sessile drop technique, in determining contact angles and then the surface energy of pharmaceutical powders was assessed. The dispersive components of the surface energy of powders determined from the DAT and IGC method ranked the powders in the same order. The dispersive component values obtained by IGC were, as expected, higher than those from the DAT, due to IGC probing the highest energy sites on the powder surface. IGC and triboelectric studies allow materials to be characterised in terms of their electron donating-accepting tendencies, so inter-relationships between the data from the two techniques were explored. Although the data set was limited, there appeared to be a correlation between the charges developed by the powders on contact with stainless steel and the ratio of the electron-donating to electron-accepting tendencies of the materials as obtained from IGC.
The mechanical properties of elongated tablets of different thickness prepared at a range of pressures with surfaces that are flat or curved, have been determined by application of a flexure test. The strength of the tablets in terms of breaking load increases with an increase in the cross-sectional area of the tablets. To provide an improved method of comparing the strength of the tablets, the tensile strength of the specimens has been calculated from equations based on stress analysis. While an allowance for a change in thickness was provided by such a system there was a clear indication that the specimens tensile strength was still dependent on their dimensions. For equivalent central core thickness strength increased with the face curvature. This could be due to changes of the structure within the specimen during the formation process and there were clear indications that tablet porosities for equivalent compaction pressures were not equal. The differences could, however, be utilised to provide optimum conditions of curvature and central core thickness to give maximum tablet strength.
We continue our study of the common features present in drug molecules by looking in detail at drug side chains. Using shape description methods, we divide a database of commercially available drugs into a list of common drug side chains. On the basis of the atom pair shape descriptor (taking into account atom type, hybridization, and bond order), there are 1,246 different side chains among the 5,090 compounds analyzed. The average number of side chains per molecule is 4, and the average number of heavy atoms per side chain is 2. If we ignore the carbonyl side chain, then there are approximately 15,000 occurrences of side chains. Of these 15,000 approximately 11,000 are from the "top 20" group of side chains. This suggests that the diversity that side chains provide to drug molecules is quite low. We discuss ways that this work could be used to provide guidance for molecular design efforts.