Summary: Poly(3‐alkoxythiophene)s with different degrees of regioregularity were prepared using three different methodologies. It is shown that their Faraday rotation is highly dependent on the degree of regioregularity. The origin of the differences in regiospecificity of the methodologies is discussed.
Simulated intestinal fluids (SIFs) are described in the United States Pharmacopoeia (USP) and the International Pharmacopoeia
(IntPh) as recommended dissolution media for the characterization of solid drugs. This study was carried out to compare their
wettability properties. Six different model substrates were used as surrogates for solid drugs. These surrogate solid substrates
were characterized by the Lifshitz-van der Waals, electron donor and electron acceptor terms, which are the three components
of the total surface energy obtained by the van Oss model, which is based upon Young’s equation. Contact angles of the SIFs
on the surrogate solid-substrates were determined dynamically by image analysis up to five minutes after applying a drop of
the fluid on the solid surface. Observed time-dependent spreading behavior was accounted for by a linear extrapolation of
the experimental data to zero contact time to obtain the apparent equilibrium contact angle at zero time. Additionally, the
pH, osmolality and buffer capacity of the SIFs were experimentally determined. Although some differences in osmolality and
buffer capacity were observed, no statistically significant differences in the wetting properties of the three SIFs were detected.
This confirms recent findings that there are no observed differences in dissolution behavior among these simulated intestinal
fluids. Harmonization of these SIFs is thus recommended. 相似文献
