Nanomaterials and therapeutic applications Flashcards
What is nanotechnology?
Manipulation of materials at the nanoscale
What are the benefits of nanotechnology?
More efficient
Less wasteful
Complete control over process
What does macro mean?
Things we can deterct with the eyes
What does micro mean?
Thigs we can see with a light microscope
Includes cells
Down to 10^-6 of a m
What does nano mean?
Components of the cells
Need more sophisticate microscopes
What does pico mean?
Can’t theoretically see
Components of an atom
Measured using a H collider
How many units is the difference between macro-> micro-> nano -> pico?
10^-3
What effect does the increase of SA:V of molecules on a nanoscale have on properties of molecules?
Changes thermal, mechanical and catalytic properties of the molecules
What is a material that reflects the tunability of nanotechnology to fundamental properties without altering the chemical composition?
Carbon
What are the different forms we can find carbon?
Soot
Graphite
Buckyball
Graphene
Nanotubes
What is soot?
Amorphous or randomly organised carbon
Naturally ocurring
Manipulating the structure of this material on a nanoscale produces man-made nanomaterials
What is graphite?
Hexagonal grids of carbon
Sea of free electrons above and below the plane
Layers allowed to slide past one another
What is a buckyball?
Hollow cage ligke structure
Used for drug delivery
What is Graphene?
One atom thick sheets of carbon
Almost 2D materials
Electrons can move around to form superconductors - conductivity can be altered by changing orientation of the stacking of these layers
What are Nanotubes?
Rolled up graphene sheets
Thermally conductive
Allows to package things
Why is it useful to use nanotechnology in medicine?
Most body interactions happen on as nanoscale
Enxymatic reactions
Cell to cell communication
What are 3 ways in which we can use nanotechnology in medicine?
Diagnostics
Treatment
Monitoring
How can nanotechnology be used to diagnose conditions?
Detect and identify markers for the disease
Biosensors and microarrays
What are the three parts of diagnostics using nanomaterials?
- Sample - urine, cell culture and food
- Sample is detercted by a bioreceptor of biological component
- Electical interface transduces the signal resulting from that interaction into another signal that can be quantified
What is an example of nanomaterials used for diagnostic purposes?
Microarray
Grid-like array of tiny spots of nucleic acid
Attached to solid substrate
Allows to screen for many thousands of genes at once
Can map entire genomes - each dot represents one gene, used in genomics and drug screening
How can nanoparticles be used to treat conditions?
Nano-vehicle -> drug delivery
Tissue engineering
Regenerative medicine - nanocoatings and nanocomposites
How do nanoparticles designed for drug delivery escape opsonisation by the immune system?
Surface of nanoparticles is conjugated with proteins and polymers
What is another advantage of coating nano-vehicles with proteins?
Prevent clearance
More time for drug to be taken up by the target tissues
What is another strategy used by nano-vehicles to enhace they uptake of drugs by tissues?
Nano-vehicles can adhere to antibodies, ligands and peptides
To enhance uptake in tissues
How can nanoparticles be used for monitoring of conditions?
Imaging purposes
What is an example of a nanoparticle readily used for imaging purposes?
Gold nanoparticles
Exhibit tumour retention time
What determines the migration of imaging nanoparticles to different parts of the body?
Size
Charge
Surface ligand
How do nanovehicles accumulate at tumour sites?
Leach out from leaky tumour vasculature into surrounding tissue
Retained at tumour sites due to dysfunctional lymphatic drainage system
= enhanced permability and retention effect
What detemines the distribution of nano vehicles in cancer-striken patient?
Tumour cell growth gradient
Intertumour pressure
How do nanoparticles target tumours?
Nanoparticles target the tumour using:
Molecular ligands - antibodies and peptides
That recognise protein targets and receptors overexpressed on the surface of tumour cells
Disadvantages of nano-vehicle drug delivery
Long term tocity of nanoparticles hasn’t been established
Clearance time
Undesired accumulation in non-target tissues following delivery routes
Non-biodegradable particles
How can nanoparticles be used to engineer tissues?
Can be used to communicate and interact with surrounding environement
Nanoconstructs designed to create synthetic tissues where cells can grow
Nanomaterials can also be used to build cell-responsive scaffolds - mimic ECM
How must nanoconstructed engineered tissue match organic matter?
Nanomaterials must match organic matter in:
Mechanical properties
Surface chemistry
Typography
Example where nanomaterial is used as disinfectant
Impregnate catheters with light-activatable dyes and gold nanoparticles
Lazer light of specific wavelenght is introduced up the lumen of the catheter
Reactivity of gold nanoparticles and dyes yield ROSs
Destroy cells and produce antimicrobial effects
What is the range of size of nanoengineered systems?
1 - 100 nm
What are the different types of materials that can make up nanomaterials?
Organic/ inorganic
Biodegradable/ non-biodegradable
What factors can modulate nanoparticle distribution in the body?
Size
Chemical composition
Hydrophobicity
Surface charge
Shape
What are the different shapes of nanoparticles?
Rod-shaped -> gold
Spherical -> silicon
Icosahedral
What pathogen do nanomaterial shapes mimic?
Viruses - effective biological nanomachines
Mimic their efficacy of cellular uptake
What is a theranostic?
Describes multifunctionalizatin of nanoparticles
Can incorporate therapeutic and imaging agents into one nanoparticle
What are advantages of theranostics?
Improves prognosis of conditions
How do nanoparticles interact with host?
Via the nano-bio interface
What are the 3 components to the nano-bio interface?
Nanoparticle surface physiochemical composition
Interaction with components surrounding the medium - proteins and aq environment in blood
Contact zone or interface with biological surface
What does the nanoparticle surface physiochemical composition determine?
Whether the nanoparticle is biodegradable or not
What does the contact zone with biological substrate refer to?
How the nanoparticle binds to the CSM on target cells
