W26 Targeted Drug Delivery

Question 1

What is the Renal clearance equation?

Answer 1

Renal clearance= Glomerular filtration of unbound drug + Tubular secretion - Tubular reabsorption

Question 2

Hypothetically, what particle size is required for the local targeting of:
1. Glomerulonephritis
(inflammation of glomeruli/tiny filters)
2. Tubulointerstitial nephritis
(inflammation that affects the tubules of the kidneys and the interstitial tissue)

Answer 2

1. > 10nm
2. <10nm

Question 3

Liver targeting

Answer 3

1. Biliary excretion (endocytosis and enzymatic breakdown by hepatocytes= bile= gut)
2. Phagocytosis

Particles which avoid RES clearance and have favourable size and charge to pass through the liver sinusoidal fenestrae
(<100-150nm)

Question 4

What are liposomes?

Answer 4

Vesicles composed of a phospholipid bilayer consisting of one (unilamellar) or more (multilamellar) concentric spherical layers enclosing an aqueous centre

Question 5

What are the differences between micelles and liposomes?

Answer 5

Micelle- Unilayer membrane
Liposome- Bilayer membrane

Question 6

Dendrimers

Answer 6

• Synthetic macromolecules, monodispersed with well-defined treelike 3D architecture and composition
• Highly branched
  constructs formed from
  a central core which
  define their initial
  geometry, tend to be
  spherica
• Small molecules can
  be trapped in spaces
  within the
  dendrimer

Question 7

Albumin nanoparticles

Answer 7

• Albumin chemical structure and conformation allows interaction with many different drugs, potentially protecting them from elimination and metabolism in vivo