Gerrit Borchard

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Chitosan microparticles as carriers for GRA-1 protein vaccine were prepared and characterized with respect to loading efficiency and GRA-1 stability after short-term storage. Chitosan nanoparticles as carriers for GRA-1 pDNA vaccine were prepared and characterized with respect to size, zeta potential, and protection of the pDNA vaccine against degradation(More)
Pulmonary gene delivery is thought to play an important role in treating genetically related diseases and may induce immunity towards pathogens entering the body via the airways. In this study we prepared poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles bearing polyethyleneimine (PEI) on their surface and characterized them for their potential in(More)
Efficient non-viral gene delivery based on cationic polymers as DNA-condensing agents is dependent on a variety of factors, e.g. complex size, complex stability, toxicity, immunogenicity, protection against DNase degradation, and intracellular trafficking and processing of the DNA. This review examines the advances in the application of chitosan and(More)
N-Trimethyl chitosan chloride (TMC) is a soluble chitosan derivative that shows effective enhancing properties for peptide and protein drug transport across mucosal membranes. TMC was synthesized by reductive methylation of chitosan in an alkaline environment at elevated temperature. The number of methylation process steps and the base used in the process(More)
The lungs have received attention as a portal for drug delivery in tuberculosis (TB) from researchers addressing diverse objectives. These include: (a) targeting alveolar macrophages that harbour TB bacilli; (b) maintaining high drug concentrations in lung tissue; (c) systemic delivery of potent or second-line anti-TB agents; and (d) delivering agents that(More)
The striking advantage of mucosal vaccination is the production of local antibodies at the sites where pathogens enter the body. Because vaccines alone are not sufficiently taken up after mucosal administration, they need to be co-administered with penetration enhancers, adjuvants or encapsulated in particles. Chitosan easily forms microparticles and(More)
In the present study, we evaluated polyethylenimine (PEI) of different molecular weights (MWs) as a DNA complexing agent for its efficiency in transfecting nondifferentiated COS-1 (green monkey fibroblasts) and well-differentiated human submucosal airway epithelial cells (Calu-3). Studying the effect of particle size, zeta potential, presence of serum(More)
In this report we present in detail a non-invasive pulmonary application method that can be a useful tool in studying drug and vaccine delivery to the lower airways. In this method the formulation is sprayed directly into the lungs of mice via the endotracheal route using a MicroSprayer aerolizer. Mean droplet size produced was 8 microm, appropriate for(More)
The volatile fatty acid, (R)/(S)-3-hydroxy-3-methylhexanoic acid ((R)/(S)-HMHA), and the human specific volatile thiol, (R)/(S)-3-methyl-3-sulfanylhexan-1-ol ((R)/(S)-MSH), were recently identified as major components of human sweat malodor. Their 2 corresponding precursors were subsequently isolated from sterile and odorless axillary secretions. The(More)
Chitosan is a biocompatible polysaccharide of natural origin that can act as a permeation enhancer. In this study, we used an integral in vitro/in vivo correlation approach to: a) investigate polysaccharide-mediated absorption kinetics of the peptide drug octreotide across mammalian airway epithelium, b) assess formulation toxicity, c) correlate the(More)