OBJECTIVES Microencapsulation of drugs into preformed polymers is commonly achieved through solvent evaporation techniques or spray drying. We compared these encapsulation methods in terms of controlled drug release properties of prepared microparticles and investigated the underlying mechanisms responsible for the 'burst release' effect. METHODS Using two different pH-responsive polymers wit...

Silica scaling potential from geothermal waters puts limits on to what extent the heat from the water can be extracted. Once the waters become over-saturated with respect to amorphous silica, the handling of such waters becomes problematic. Many methods have been proposed to address this problem. One of them is aging the geothermal waste water allowing monomeric silica in excess of amorphous si...

In this paper, the electrochemical behaviour of several parabens preservatives, i.e. esters of p-hydroxybenzoic acid, methyl-, ethyl- and propyl-4-hydroxybenzoates as methyl-, ethyl- and propyl-parabens (MB, EB, and PB), has been investigated at a commercial boron-doped diamond electrode (BDDE), especially in the anodic potential range, in both hydro-alcoholic and aqueous media. The cyclic volt...

Rutin is a well-known antioxidant from the group of flavonoids. Its use in cosmetic dermal products is, however, limited due to its poor water solubility. In order to increase rutin saturation solubility and improve the diffusion to the skin, rutin nanocrystals were produced by the smartCrystal process, e.g., bead milling followed by high pressure homogenization. Rutin nanocrystals were further...

Darifenacin is a urinary antispasmodic. The oral absorption of darifenacin is poor due to its low solubility and poor bioavailability (15-19%). Darifenacin was complexed with hydroxylropyl beta-cyclodextrin (Hpβ-CD). The best results were obtained with the coevaporation that interacts in a 1 : 1 drug : cyclodextrin molar ratio. The solid inclusion complexes were found to be amorphous in the cha...

Nanosuspension technology has been developed as a promising candidate for efficient delivery of hydrophobic drugs. It could maintain the required crystalline state of the drug with reduced particle size, leading to an increased reporting on dissolution rate and therefore improved bioavailability. In this paper, we report on the preparation of ketoprofen (KTF) nanosuspension by high-pressure hom...

A safe, practical, clinically applicable, noninvasive method for measuring local cerebral blood flow (LCBF) using inert xenon (Xes) and a 60 sec CT scanner has been developed in the baboon. Direct measurement of expired Xes concentration after short inhalation (4--7 min) of 40% Xes and the use of computer-programmed autoradiographic formulas allow accurate, reproducible measurements of LCBF usi...

The metastable zone width (MSZW) and induction time of CoSO4 in the presence H2SO4 were measured at various operating conditions by polythermal isothermal methods, respectively. Raman spectroscopy UV–Vis have been successfully adopted for measuring solubility CoSO4. nucleation parameters estimated with a self-consistent Nývlt-like approach classical 3D theory approach. results show decrease an ...

was dissolved from the soil; Le., equilibrium was ap­ Soils in the laboratory were reacted with agricultural drainage­ and distilled waters at various carbon dioxide (COl) levels. The soil water solutions yielded different Ion activity product (lAP) values than that of calcite, depending on experimental technique and whether calcite "equilibrium" is approached from supersaturation or under­ sat...

Cholesterol crystallization in bile is affected by phosphatidylcholine (PtdCho) hydrophobicity. The aim of the present study was to determine whether PtdCho species modulate the metastable-labile limit and equilibrium solubility of cholesterol in the micellar phase of bile, thereby altering the distribution of cholesterol to biliary lipid carriers and thus influencing cholesterol crystallizatio...