nanomedicine 1, 2

Question 1

what is nanotechnology

Answer 1

study of things that when reduced in size they display unique different physiochemical properties than when compared to bulk material

or

creation of useful/functional devices or material through control/manipulation of matter on nanometre length scale

Question 2

what is nanomedicine

Answer 2

use of nanotechnology to treat disease

Question 3

ways nanoparticles treat cancer

Answer 3

lipid based nanocarriers- high degree of biocompatibility, encapsulates wide range

polymer based nanocarriers- suitable for development due to ease and adaptability, eg. polymeric NP, dendrimers, polymer micelles

inorganic nanoparticles- diagnosis/treatment due to superior physiochemical properties like magnetic, thermal, optical, catalytic, excellent functions like imaging, targeted delivery and controlled release

viral nanoparticles-plant virus nanoparticles can be functionalised to be taken up by cancer cells

drug conjugates- class of biopharmaceutical drugs designed to enhance efficacy of therapeutic targeting by allowing for targeting enhanced dose delivery

Question 4

name 6 nanoparticle types

Answer 4

liposomes, gold nanoparticles, carbon nanotubes, iron oxide nanoparticles, quantum dots, polymer micelles

Question 5

describe the characteristics of liposomes

Answer 5

present high loading efficacy ensuring a high dose delivered, encapsulates drugs by protecting them and designed to release on a stimulus like pH or light

Question 6

describe the characteristics of gold nanoparticles

Answer 6

display unique optical characteristics at nanoscale, due to interactions with light photons giving the nanoparticle different colours depending on size

Question 7

describe the characteristics of carbon nanotubes

Answer 7

display unique electrical properties compared to bulk material of carbon which doesnt display it, used to conjugate with drugs so they release drug on electrical stimulation

Question 8

describe the characteristics of iron oxide nanoparticles

Answer 8

superior magnetic and thermal characteristics at nanoscale, used to develop imaging and thermal stimulated killing of cancer cells

Question 9

describe the characteristics of quantum dots/semi conducting crystals

Answer 9

develop theranostics due to their unique optical properties, when exposed to light a unique light is produced depending on their nanoscale size and material properties, results from an electron being excited and forming a valent bond to a conduction band, energy required to do this is called a band gap, band gap=distance between valence band of electrons and the conduction band, band gap is minimum energy required to excite and electron up to a state in the conduction band where it can participate in conduction

-when bandgap lies in visible spectrum, a change in bandgap with size means change in colour

Question 10

describe the characteristics of polymer micelles

Answer 10

unique mechanical and chemical phenomena at nanoscale, used to develop advanced drug delivery systems eg. swelling causes release of an encapsulated drug

Question 11

main aims of nanotechnology

Answer 11

-create new properties- to understand control and create nanostructures

-improve ability to image/measure/manipulate matter on nanoscale to exploit those properties and functions

-ability to integrate those properties and functions into systems spanning nano to macroscopic scales

Question 12

benefits of nanotechnology based drug delivery systems

Answer 12

-improved drug absorption
-reduced side effects
-targeted drug delivery
-controlled drug release
-creates more efficient/targeted/controlled systems

Question 13

limitations of current drug delivery systems

Answer 13

-low drug absorption
-quick metabolism and excretion
-side effects

Question 14

name different physical and chemical properties depending on size

Answer 14

optical properties, band gap energy, melting point, specific heat capacity, surface reactivity

Question 15

advantages of nanoscale devices in medicine

Answer 15

-devices smaller than 50nm can easily enter most cells
-devices smaller than 20nm can transit out of blood vessels
-devices are capable of holding thousands of small molecules like drugs and contrast agents

Question 16

major areas of development of nanomedicine

Answer 16

-prevention and control
-early detection
-imaging diagnostics
-multifunctional therapeutics

Question 17

chemotherapy non targeted delivery, what pathway is used, what is it formulated with

Answer 17

uses endogenous albumin pathways, formulated with albumin obviates the need for toxic solvents, increase drug delivery initiating albumin receptor mediated transcytosis

Question 18

what is transcytosis

Answer 18

type of transcellular transport in which various macomolecules are transported across the interior of a cell

-macromolecules captured in vesicles on one side, drawn across cell and ejected onto the other side

Question 19

challenges/problems with cancer therapeutics in nanomedicine

Answer 19

delivery-nanoparticles difficult to deliver to tumours in the body, can be intercepted by immune system or other organs

targeting-difficult to target to specific cancer cells, can be taken up by healthy cells

toxicity-toxic to healthy cells causes side effects

cost-expensive to produce, makes them inaccessible to some patients

regulatory hurdles-regulatory process still in development, difficult to get new products approved for clinical use

Question 20

binding strategies(?)

Answer 20

hydrophobic/hydrophilic drug, PEG, transferrin, cell penetrating peptide, fibronectin (ligand for integrin receptor), folate, fibroblast growth factor, matrix metalloproteinase ligand, antibody, genetic material, antibody fragment

Question 21

stimuli responsive delivery in chemotherapy-cancer characteristics can be taken advantage of when developing drug delivery systems eg:

Answer 21

1. leaky vascular system- enhanced permeability and retention effect
2. cell surface receptors/markers
3. inside tumour differences eg. reduced pH compared to healthy tissues

Question 22

what is ROS mediated killing stimulated by and what is ROS

Answer 22

stimulated by: light, radiation, electric fields
-causes mediated ROS production via nano particles

ROS=toxic to cells in high concentrations due to high reactivity

Question 23

gene/RNA therapy

Answer 23

causes detrimental effects to cancer, eg. stops key protein from being synthesised

Question 24

nanoparticle physical properties

Answer 24

size, geometry, surface charge, porosity, elasticity, surface hydrophobicity, roughness, curvature, electronic, magnetic, optical

Question 25

nanoparticle structure/chemical composition

Answer 25

liposomes, polymeric NOs, micelles, dendrimers, protein NPs, viral NPs, exosomes, metal and metal derived NPs, carbon nanomaterials

Question 26

nanoparticle targeting ligands

Answer 26

small molecules, antibodies and fragments aptamers and nucleic acids, proteins and peptides, sugars

Question 27

problems with cancer therapeutics in standard delivery systems

Answer 27

limited targeting, biodegradation of drug, rapid drug clearance, low specificity

Question 28

vectors in nanomedicine (1st 2nd 3rd gen)

Answer 28

1st generation=nanospheres and nanocapsules

2nd generation=nanoparticles coated with hydrophilic polymers (PEG)

3rd generation=biodegradable core and polymer coating with a membrane recognition ligand

Question 29

why nanoparticle is good for cancer

Answer 29

delivers directly to tumour, protects drug from being degraded, enhances drug delivery into diseased tissue, controls cell uptake allowing oncologists more control on determining how effective treatment is, prevents drug from interacting with normal cells

Question 30

things that trigger nanoparticles to destroy tumours from within

Answer 30

thermo, magnetic, pH, light, electrical

Question 31

difference between active and passive targeting

Answer 31

active targeting receptor makes it selective
passive targeting- shape/charge/lipophilicity makes it more likely to pass membrane of diseased cell

Question 32

types of nanotheranostics being developed

Answer 32

liposomes-spherical vesicles of lipid bilayer, delivers variety of drugs, imaging agents, heat

polymeric nanoparticles- made from synthetic polymers, delivers drugs, imaging agents, genes

gold nanoparticles- delivers drugs, imaging agents, heat

magnetic nanoparticles- delivers drugs, imaging agents, heat, used to guide nanoparticles to tumours using magnetic fields