Last Minute Flashcards
What size particles for nasal delivery to turbinates?
5-10um, >10um trapped in hairs,
How is reverse micelle formation achieved?
Sodium deoxycholate
In which route are tight junctions looser?
Pulmonary
How does epithelial thickness vary throughout the lungs?
From about 60um in bronchi to
hat enzymes can be found in oral mucus/saliva?
No proteases but contains esterase, amylase, lipase, phosphatase.
What drugs can be delivered via the sublingual/buccal route?
insulin, inhaler: RapidMist delivery system. Insulin, surfactant, solubiliser, micelle creating agent, emulsifying agent.
Buprenorphine, naloxone, Actiq lollipop, buccal testorone, Striant
Nitroglycerin
What is special about the vaginal structure?
Intercellular channels are present.
What could vaginal rings be used to treat?
Contraception HRT IVF therapy Microbicides (HIV, herpes) Reservoir, matrix, pod forms.
What rings exist?
NuvaRing
What is the release area of Eudagrit L 100?
Jejunum: pH 6
What is the release area of Eudagrit L 30?
Doudenum pH 5.5
What release profiles are possible from Geomatrix?
Swelling device.
Zero order, quick-slow, slow-quick, binary, positioned, accelerated, delayed, cardiovascular, multiple pulse.
How can the length of cross links influence drug release?
Larger links - more drug release as not as tight matrix
For chemically controlled DDS, in surface erosion devices what is the relationship between polymer degradation and water ingress?
Polymer degradation leads to water ingress and drug release.
Bulk erosion: water ingress leads to polymer degradation
Class II POE hydrolysis (surface erosion) is what?
Acid catalysed
Class IV POE degradation is what?
Self-catalysed
What is electro spinning?
Syringe driver + polymer solution + high voltage power supply.
Tetracycline release to treat bacterial infections.
PCL
PEVA
What can electrospinning be used for?
Suspensions and emulsions, reduce or eliminate burst release, coaxial electrospinning allows core/sheath nanofibres to be generated.
What are benefits of Mesoporous Silica Nanoparticles?
Inert
Thermally stable
Easy to functionalise
Following drug loading, pores can be capped with Nanoparticles that can be selectively removed by pH, light, magnetism, antigen, S-S reduction or saccharide.
How can the rate of degradation of Gliadel wafers be increased?
Increase the amount of sebacic acid in the PCPP:SA mixture.
Treats malignant gliomas. Brain.
What is NK012?
Targets DNA topoisomerase I.
PEG+ SN38 = NK012
Takes advantage of EPR effect.
What is C. novyi?
An obligate anaerobes bacteria that can colonise tumours, also haemolytic so able to disrupt lipid bilayers.
Many prodrug passive targeting approaches include a polymer or Nanoparticles carrier to ensure what?
Accumulation in tumour tissue and tumour specific release.
What types of linkers can be used for pH sensitive targeting?
Imines, hydrazone, carboxylic hydrazone, acetal, ketal.
What is HSA?
Human serum albumin.
What is HER2?
Transmembrane glycoprotein over expressed.
How can single chain variable fragments (scFv) be used in active targeting?
Single chain variable fragments of antibodies penetrate tumours better and have higher specificity.
HER2 can be targeted for PDT using a scFv Ab.
What is an example of ADEPT?
Carboxypeptidase G2 (CPG2) against colorectal cancer.
What are affibodies?
Based off of Stayphlococcal protein A which binds to mammalian IgG.
EASILY generated
Scalable.
How can aptamers be used?
Aptamers - linker- drug Aptamer containing drug. Aptamer - toxin or enzyme Aptamer - liposome Aptamer - micelle Aptamer - polymer Nanoparticles
Elimination usually involves:
Cystine
Deamindation usually involves:
Asparagine and glutamine
Favoured at pH 5 and above
Disulphides bond shuffling occurs to
Cystine residues
What is the effect of removing terminal disulphide bonds?
Reduces Tm by 40 degrees.
Oxidation occurs to
Methionine and cysteine
Cross linking involves
Lysine
Thiol-disulphide exchange involves
Cysteine and cystine
Why are cyclodextrins added to protein formulations?
Suppress aggregation of proteins
Why are polysorbates used?
Preferential exclusion of solutes.
Acting as a chaperone aiding protein refolding.
Binding to hydrophobic patches of proteins.
Formation of detergent film in aqueous systems to limit protein exposure to air/water interface.
Compete with proteins in adsorbing to surfaces - glass, IV bags etc.
Applicable for lifetime of formulation
Why should polysorbates be used with caution?
Auto-oxidation can occur Hydrolytic degradation Reactive peroxides Aldehydes Immunogenicity Extent relies on: identity of protein, protein and surfactant concentration etc
