0000000000560150
AUTHOR
Jörg Kreuter
Apolipoprotein-mediated transport of nanoparticle-bound drugs across the blood-brain barrier.
Recent studies have shown that drugs that are normally unable to cross the blood-brain barrier (BBB) following intravenous injection can be transported across this barrier by binding to poly(butyl cyanoacrylate) nanoparticles and coating with polysorbate 80. However, the mechanism of this transport so far was not known. In the present paper, the possible involvement of apolipoproteins in the transport of nanoparticle-bound drugs into the brain is investigated. Poly(butyl cyanoacrylate) nanoparticles loaded with the hexapeptide dalargin were coated with the apolipoproteins AII, B, CII, E, or J without or after precoating with polysorbate 80. In addition, loperamide-loaded nanoparticles were …
Microparticles derived from marine sponge collagen (SCMPs): preparation, characterization and suitability for dermal delivery of all-trans retinol.
Abstract Collagen microparticles were prepared using marine sponge collagen. For this purpose a previous method by Rossler et al. (J. Microencapsul. 12 (1995) 49) of emulsification and cross-linking of native calf collagen was modified. The modified method for sponge collagen microparticles (SCMPs) achieved a yield of 10%. Scanning electromicroscopic photographs showed spherical particles with a diameter of 120–300 nm and photon correlation spectroscopic measurements indicated particle size range from 126 (±2.9) to 2179 (±342) nm. This broad size distribution was caused by some agglomerates that could not be destroyed by ultrasonication. The surface charge was measured as a function of pH. …
Marine sponge collagen: isolation, characterization and effects on the skin parameters surface-pH, moisture and sebum
A previously described isolation procedure for collagen of the marine sponge Chondrosia reniformis Nardo was modified for scaling-up reasons yielding 30% of collagen (freeze-dried collagen in relation to freeze-dried sponge). Light microscope observations showed fibrous structures. Transmission electron microscopy studies proved the collagenous nature of this material: high magnifications showed the typical periodic banding-pattern of collagen fibres. However, the results of the amino acid analysis differed from most publications, presumably due to impurities that still were present. In agreement with earlier studies, sponge collagen was insoluble in dilute acid mediums and all solvents inv…
Uptake mechanism of ApoE-modified nanoparticles on brain capillary endothelial cells as a blood-brain barrier model.
Background The blood-brain barrier (BBB) represents an insurmountable obstacle for most drugs thus obstructing an effective treatment of many brain diseases. One solution for overcoming this barrier is a transport by binding of these drugs to surface-modified nanoparticles. Especially apolipoprotein E (ApoE) appears to play a major role in the nanoparticle-mediated drug transport across the BBB. However, at present the underlying mechanism is incompletely understood. Methodology/Principal Findings In this study, the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells was investigated to differentiate between active and passive uptake mechanism by flow cytome…