Yechezkel Chezy Barenholz

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Doxil®, the first FDA-approved nano-drug (1995), is based on three unrelated principles: (i) prolonged drug circulation time and avoidance of the RES due to the use of PEGylated nano-liposomes; (ii) high and stable remote loading of doxorubicin driven by a transmembrane ammonium sulfate gradient, which also allows for drug release at the tumor; and (iii)(More)
Pegylated liposomal doxorubicin (doxorubicin HCl liposome injection; Doxil or Caelyx) is a liposomal formulation of doxorubicin, reducing uptake by the reticulo-endothelial system due to the attachment of polyethylene glycol polymers to a lipid anchor and stably retaining drug as a result of liposomal entrapment via an ammonium sulfate chemical gradient.(More)
Gradients of ammonium sulfate in liposomes [(NH4)2SO4]lip. > [(NH4)2SO4]med. were used to obtain 'active' loading of amphipathic weak bases into the aqueous compartment of liposomes. The loading is a result of the base exchange with the ammonium ions. This approach was applied to encapsulate anthracyclines and acridine orange inside the liposomes at very(More)
Ultrasound is used in many medical applications, such as imaging, blood flow analysis, dentistry, liposuction, tumor and fibroid ablation, and kidney stone disruption. In the past, low frequency ultrasound (LFUS) was the main method to downsize multilamellar (micron range) vesicles into small (nano scale) unilamellar vesicles. Recently, the ability of(More)
Phase transitions in closed vesicles, i.e., microenvironments defined by the size of the vesicle, its contents, and permeability of its membrane are becoming increasingly important in several scientific disciplines including catalysis, growth of small crystals, cell function studies, and drug delivery. The membrane composed from lipid bilayer is in general(More)
Liposomes can be loaded with weak acids and bases, which exist in solutions in equilibrium with membrane permeable uncharged form, using various gradients across their membranes. Because in some cases the estimated drug concentration in the loaded liposomes exceeds their aqueous solubility we investigated the physical state of the liposome encapsulated(More)
Some therapeutic liposomes and lipid excipient-based anticancer drugs are recognized by the immune system as foreign, leading to a variety of adverse immune phenomena. One of them is complement (C) activation, the cause, or major contributing factor to a hypersensitivity syndrome called C activation-related pseudoallergy (CARPA). CARPA represents a novel(More)
This work describes a versatile and universal polycation system based on oligoamines grafted on natural polysaccharides that is capable of complexing various plasmids and administering them into various cells in high yield to produce a desired protein. These polycations are expected to better meet the requirements for effective complexation and delivery of(More)