What Are Biomaterials?
What is the general term for any substance (other than a drug), synthetic or natural, used to treat, augment, or replace tissue, organ, or body function?
A biomaterial!
What term describes proteins that cancer cells overexpress on their surface, which healthy cells lack or have much less of?
Cancer biomarkers (surface receptors)
What type of molecule makes up the bilayer membrane of a liposome?
Lipids
Name the three types of metallic nanoparticles introduced in class
Silver, iron oxide, and gold nanoparticles
What are the two basic structural forms of polymeric nanoparticles shown in class — one where drug is entrapped inside a hollow shell, and one where drug is spread through a solid sphere?
Nanocapsules and nanospheres
Name two examples of natural, protein-based biomaterials mentioned in class.
Silk, Collagen, Fibrin, Gelatin.
What is the name for the passive buildup of nanoparticle drugs at a tumor site, caused by the tumor's leaky blood vessels and poor drainage?
EPR
A phospholipid has a hydrophilic head and hydrophobic tail. What term describes this dual nature that lets phospholipids self-organize into a membrane?
Amphipathic
Which metal is described as the most common nanoparticle material because it's easy to fabricate, highly biocompatible, and has great optical properties?
Gold
What term describes polymers that change shape or structure in response to an external trigger like heat, light, pH, or enzymes?
Stimuli-responsive (or 'smart') polymers
What term describes a material's ability to perform well in the body without causing toxic or harmful effects?
Biocompatibility
What is it called when a nanoparticle is engineered with a ligand, like an antibody or peptide, that specifically binds to a receptor on cancer cells?
Active targeting
What molecule is commonly inserted into liposome membranes to increase fluidity and decrease rigidity of the bilayer?
Cholesterol
What therapy uses nanoparticles and an alternating magnetic field to raise tumor tissue temperature to about 40–43°C?
Magnetic hyperthermia
Why do pH-responsive nanoparticles release their drug cargo more readily in the acidic tumor microenvironment?
Acidic or basic groups on the polymer become ionized, increasing electrostatic repulsion and causing the nanoparticle to expand and release its trapped drug.
Name one synthetic polymer biomaterial mentioned in class.
Poly-ethylene glycol (PEG), Polyglycolide (PGA), Poly-lactic-co-glycolic acid (PLGA), Poly-D,L-lactide (PDLLA), Poly-e-caprolactone (PCL).
Name one type of molecule that can be used as a targeting ligand on a nanoparticle's surface
antibody, antibody fragment, peptide, protein, sugar/carbohydrate, aptamer
What polymer coating is commonly added to liposomes (like in the drug Doxil) to help them evade the immune system and circulate longer in the blood?
PEG
What therapy uses near-infrared or visible light to activate nanoparticles, generating heat and reactive oxygen species (ROS) to kill cancer cells?
Photothermal therapy.
Name one advantage of polymeric nanoparticles mentioned in class.
high tunability (can modify shape/size/design and drug release rate), easy and cheap to fabricate in large quantities, delivers high drug concentrations, can be designed to respond to different stimuli
what are the two broad origin categories biomaterials fall into?
Natural biomaterials and synthetic biomaterials
What is the general term for the process by which a nanoparticle, once bound to a cell surface receptor, gets pulled inside the cell?
Receptor-mediated endocytosis.
Name one advantage and one disadvantage of using liposomes as drug delivery vehicles.
advantage (e.g., non-toxic/biodegradable, improved pharmacokinetics, easy to functionalize, selective passive tumor targeting) and any one disadvantage (e.g., high production cost, short half-life, drug leakage, low water solubility)
In chemodynamic therapy, what specific chemical reaction — driven by iron oxide nanoparticles — generates damaging hydroxyl radicals inside cancer cells?
Fenton reaction
Name one disadvantage of polymeric nanoparticles mentioned in class.
Mainly biotoxicity