nn Flashcards
What is nanotechnology?
Nanotechnology combines science and technology with the ability to manipulate structures and properties at the nanoscale size range, which lies between 1 and 100 nm.
What are nanoparticles (NPs) used for in medicine?
NPs provide a new tool to address unmet clinical needs with a significant improvement in drug delivery.
How can nanoparticles be classified?
Nanoparticles can be classified as:
* Inorganic nanoparticles
* Organic nanoparticles
What are examples of inorganic nanoparticles?
Inorganic nanoparticles mainly include:
* Silver (Ag)
* Gold (Au)
* Copper (Cu)
* Magnesium (Mg)
* Titanium (Ti)
* Platinum (Pt)
* Zinc (Zn)
* Iron (Fe)
What are organic nanoparticles and why are they important in drug delivery systems?
Organic nanoparticles are significant in drug delivery systems and comprise liposomes, dendrimers, polymers, etc.
What is the purpose of nanoparticle formulation in drug delivery?
The formulation of nanoparticles aims for:
* Passive targeting: accumulation at active sites due to biophysical properties.
* Active targeting: surface modified particles with specific moieties to reach specific organs.
What can be incorporated into nanoparticles for active targeting?
Incorporation can include:
* Antibody fragments
* Peptides
* Hormones
* Aptamers
* Sugars
What are liposomes?
Liposomes are vesicles consisting of phospholipid bilayers that resemble a cell membrane, widely used as nanocarriers in drug delivery systems.
What are the advantages of using liposomes in drug delivery?
Liposomes provide advantages such as:
* Size
* Biocompatibility
* Biodegradability
* Low toxicity
* Potential to encapsulate hydrophilic, lipophilic, and amphiphilic drugs.
What are dendrimers?
Dendrimers are monodisperse macromolecules with a structure composed of:
* An inner core
* A branching unit called generation
* An outer surface with numerous valent functional groups.
What are polymeric nanoparticles?
Polymeric nanoparticles are spherical-shaped solid colloidal particles composed of biocompatible and biodegradable polymers, sized from 10 nm to 1000 nm.
What types of polymers can be used in polymeric nanoparticles?
Types of polymers include:
* Natural polymers (e.g. chitosan, alginate, albumin, gelatin, dextran)
* Synthetic polymers (e.g. polylactic acid (PLA), polyglycolide (PGA), poly(L-lysine), polyaspartic acid, poly-alkyl cyanoacrylate)
What are the mechanisms of drug release from a polymer matrix?
Drug release mechanisms include:
* Surface erosion of the polymeric matrix
* Cleavage of polymer bonds on the surface or in the bulk
* Diffusion of drugs physically entrapped
What factors influence drug release from nanoparticles?
Polymer physical parameters influence:
* Drug release
* Toxicity
* Biocompatibility of polymers.
What are external stimuli that can trigger drug release?
External stimuli include:
* Cellular triggers
* Biochemical triggers (enzymes)
* Physical triggers (light, temperature, ultrasound)
* Chemical triggers (pH)
What are endogenous stimuli that can trigger drug release?
Endogenous stimuli include:
* Changes in pH
* Redox state
* Ionic content within tissues and cells
What is Doxil(r)?
Doxil(r) is a liposome formulation of Doxorubicin used in clinical drug delivery targeting.
What are the pharmacological properties of Doxorubicin?
Doxorubicin is an anthracycline that:
* Acts as a cytostatic drug
* Intercalates into DNA and inhibits topoisomerase II
What are the FDA approval details for Doxil(r)?
Doxil(r) received FDA approval in 1995 and has a half-life of 55 hours, remaining stable in blood.
What features are important for a good drug delivery product?
Features include:
* Drug should be available to tumor cells
* Nano-scale for extravasation from blood vessels into tumor tissues
* Prolonged plasma circulation for drug accumulation in tumors.
