studying-soft-matter-biological-systems-over-wide-length-scale-from

Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2

The KWS-2 SANS diffractometer is dedicated to the investigation of soft matter and biophysical systems covering a wide length scale, from nm to &#181;m. ...

Forschungszentrum Jülich GmbH

A set of biorelevant media "fasted-state simulated intestinal fluid with cholesterol (FaSSIF-C)" for the in vitro study of intestinal drug dissolution in the duodenum was developed. These contain cholesterol at the same levels as in human bile: the cholesterol content of FaSSIF-7C is equivalent to healthy female, FaSSIF-10C to healthy male persons, and FaSSIF-13C to several disease cases that lead to gallstones. The fluids were studied in three aspects: biocompatibility, intestinal nanostructure, and solubilizing power of hydrophobic drugs of the BCS class II. The biocompatibility study showed no toxic effects in a Caco-2 cell system. The drug-solubilizing capacity toward Fenofibrate, Danazol, Griseofulvin, and Carbamazepine was assessed as example. It varied with the cholesterol content widely from a fourfold improvement to a twofold reduction. The nanostructure study by dynamic light scattering and small-angle neutron scattering indicated vesicles as the main component of FaSSIF-C in equilibrium (>1 h), but at high cholesterol content, larger particles were observed as a minor contribution. The neutron experiments indicated the presence of complex micelle-vesicle mixtures, even after 1 h development of fed-state bile model to FaSSIF. The results indicate that cholesterol affects some drugs in solubilization and particle size in intestinal model fluids.

Fasted-state simulated intestinal fluid "FaSSIF-C", a cholesterol containing intestinal model medium for in vitro drug delivery development.

Following demand from the user community regarding the possibility of improving the experimental resolution, the dedicated high-intensity/extended Q-range SANS diffractometer KWS-2 of the Jülich Centre for Neutron Science at the Heinz Maier-Leibnitz Center in Garching was equipped with a double-disc chopper with a variable opening slit window and time-of-flight (TOF) data acquisition option. The chopper used in concert with a dedicated high-intensity velocity selector enables the tuning at will of the wavelength resolution Δλ/λ within a broad range, from 20% (standard) down to 2%, in a convenient and safe manner following pre-planned or spontaneous decisions during the experiment. The new working mode is described in detail, and its efficiency is demonstrated on several standard samples with known properties and on a completely new crystallizable copolymer system, which were investigated using both the conventional (static) and TOF modes.

Noemi Kinga Szekely

Jülich Centre for Neutron Science Outstation at MLZ

Forschungszentrum Jülich GmbH

Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2

Noemi Kinga Szekely

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Jülich Centre for Neutron Science Outstation at MLZ

Forschungszentrum Jülich GmbH

Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2

Jülich Centre for Neutron Science Outstation at MLZ