Mock Exam Qs

Question 1

What are the GIT obstacles for orally administered nanoparticles? *

Answer 1

Oral drugs need to have high stability and penetrate the intestinal epithelium to have high bioavailability

Lumen - GI fluids can cause pH-triggered dissolution of NPs

Nanoparticle properties – lead to aggregation, enzymes also degrade NPs

Mucus layer - Can trap or impede nanoparticles so they don’t reach the epithelial cells. Epithelial cells are tightly joined creating a barrier which large molecules cannot pass

Cellular uptake - nanoparticles are often taken up by absorptive enterocytes *

Lysosome - Eventually degradation in lysosome after being taken up by macrophages or neutrophils via phagocytosis

Question 2

What are the obstacles for pulmonary, nasally and topically administered nanoparticles? *

Answer 2

Require efficient transport of the drug across the epithelium

Question 3

What are the barriers to overcome in the BBB? *

Answer 3

The BBB restricts the diffusion of large or hydrophilic molecules into the CNS.

Liposome and nanosphere NPs may be able to deliver across the BBB.

Question 4

What are the challenges of drug delivery to tumours? *

Answer 4

Large areas of tumour may be poorly perfused

Impaired lymphatic drainage in tumours lead to higher interstitial fluid pressure, which causes limited trans-vascular transport of macromolecules