We report on a comparison between the random disorder effects of an hydrophobic (R812) or an hydrophilic (A380) aerosil on the order and dynamics of the 3βDOXYL-5α-cholestane spin probe in the liquid crystal 4-n-pentyl-4’-cyanobiphenyl (5CB) using the ESR technique. Increasing the aerosil concentration up to 3 wt % the probe order parameter is depressed with a larger effect for the hydrophilic ...

This study explores the role of aerosil dispersion on activated phase transitions of bulk octylcyanobiphenyl (8CB) liquid crystals by performing heating rate-dependent experiments. Differential scanning calorimetry (DSC) was used at various heating ramp rates in order to probe the activated phase dynamics of the system. The system, LC1-xSilx, was prepared by mixing aerosil nanoparticles (7 nm i...

A high-resolution calorimetric spectroscopy study has been performed on pure glycerol and colloidal dispersions of an aerosil gel in glycerol covering a wide range of temperatures from 300 to 380 K, deep in the liquid phase of glycerol. The colloidal glycerol+aerosil samples with 0.07, 0.14, and 0.32 g of silica per cm3 of glycerol reveal activated energy (thermal) dynamics at temperatures well...

Surface solid dispersion with insoluble carriers is considered a recently developed technique, widely applied for the enhancement of solubility and dissolution of poorly water soluble drugs. The objective of this research article is to study the effect of surface solid dispersion of ketoprofen with colloidal silicon dioxide (Aerosil 200) on the dissolution rate. Surface solid dispersion (Adsorb...

The purpose of this study was to prepare a dutasteride-loaded solid-supersaturatable self-microemulsifying drug delivery system (SMEDDS) using hydrophilic additives with high oral bioavailability, and to determine if there was a correlation between the in vitro dissolution data and the in vivo pharmacokinetic parameters of this delivery system in rats. A dutasteride-loaded solid-supersaturatabl...

The present research aimed to improve the dissolution rate and bioavailability of curcumin using the potential of liquisolid technology. Twelve drug-loaded liquisolid systems (LS-1 to LS-12) were prepared using different vehicles (PEG 200, PEG 400 and Tween 80) and curcumin concentrations in vehicle (40%, 50%, 60% and 70%, w/w). The carrier [microcrystalline cellulose (MCC) PH102] to coat (Aero...

We have studied a system composed of an hydrophobic aerosil (R812) dispersed in the liquid crystal 4-n-octyl-4’-cyanobiphenyl (8CB) using the spin probe ESR technique and, in particular, we have determined, for different aerosil concentrations, the temperature dependence of the orientational order parameter 〈P2〉 and the rotational diffusion coefficient D⊥ of the probe 5-doxyl stearic acid in th...