Toxicological assessment of nanomaterials - WIP Flashcards
of nanoparticles and polymers in industry
How big are nanomaterials?
Usually 1-100nm
but up to 1000nm
What actions can nanomaterials have?
Enhanced rate of dissolution and improved bioavailability of active ingredients
Enabling targeting of active ingredients to specific sites
Effect on distribution, exposure-response profile and residence time of an active ingredient
How are nanomaterials eliminated?
Elimination of nanomaterial-protein complex occurs mainly through phagocytosis by macrophages of mononuclear phagocyte system, in liver and spleen
Small hydrophilic nanomaterials may be eliminated by kidney
What do passive and active targeting of nanomaterials rely on?
Passive targeting to different organs (e.g. liver) may be accomplished based on size or charge
Active targeting of tumors typically requires attachment of specific molecules (e.g. ligands, monoclonal antibodies, small molecules) to surface of nanomaterials that are recognized by receptors
What are some nanoparticle liposome vehicle examples?
Irinotecan for pancreatic cancer
Epaxal for hepatitis A
Doxorubicin for various cancers
Describe silver nanoparticles
silver nanoparticles have antimicrobial properties, used in a range of healthcare products like dressings for burns, skin donor and recipient sites, acne and cavity wounds, female hygiene products
What do toxicological assessments of polymeric drug delivery systems include?
General toxicology studies, genotoxicity studies, reproductive toxicity studies, carcinogenicity, dose site effects (biocompatibility, biodegrandation) and immunogenicity (hypersenitivity)
What are some special considerations for polymeric liposomes (PEG)?
PEGylated liposomes have been found to induce immunogenic responses, which can lead to hypersensitivity reactions
PEGylated liposomes also found to result in accelerated blood clearance phenomenon
