Post on 18-Dec-2015
Aspirin• Inhibits the enzyme cyclooxygenase 2 (COX-2) so the brain
does not receive a signal interpreted as pain• Nonselective and goes throughout the body, not just the
area harmed
http://easydiagnosis.com/articles/images/aspirin.jpg
http://www.greatbigstuff.com/prodpics/aspirin-blank.jpg
Smart Medicine• Goal:
– Create a system of drug delivery that delivers any drug at the right time in the right amount
– target only malignant cells and not affect healthy tissue
• How?– Nanoshells– Hydrogels– Nanoparticles– Magnetic herding– Drug releasing, tube, and cell chambers
http://www.fh.huji.ac.il/~roib/coreshell_files/image002.gif
http://www.materials.qmul.ac.uk/postgrad/images/high-m-hydrogel.jpg
hydrogel
nanoshell
Nanoshells• Beads that are three millionths of an inch wide with an outer
metal wall and an inner silicon core• Has the ability to absorb or scatter specific wavelengths of
light• Can convert light to heat and “cook” harmful cells• Can trigger drug delivery devices
http://nano.cancer.gov/resource_center/nanotech_nanoshells.asp
Hydrogels• 3D highly hydrophilic network that can absorb
compounds• Expands in water but does not dissolve• Can control the rate at which it releases drugs
http://www.chem.stevens.edu/content_images/porous_hydrogel.gif
Electronic microscopy view of porous hydrogel.
Magnetic Herding• Manipulates colloidal objects• Biology is mostly composed of colloidal material,
things larger than 10 billionths of a meter that don’t settle
• Very few things in nature are magnetically susceptible
http://www.pnas.org/cgi/content/full/102/25/8860/FIG3
Bead transport under fields rotating out-of-plane.
Copyright ©2005 by the National Academy of Sciences PNAT
Yellen, Benjamin B. et al. (2005) Proc. Natl. Acad. Sci. USA 102, 8860-8864
Fig. 1. Bead levitation and microtweezing by magnetic traps
Nanoparticles• Drugs can be linked to nanoparticles• Nanoparticles can store pharmaceutical agents and release
them at the desired target• Allows us to see cells and molecules conventional imaging
does not allow us to detect
http://nano.cancer.gov/resource_center/nano_critical.asp#why
Drug-releasing, Tube, and Cell Chambers
• Chambers have semi-permeable membranes that use diffusion to control the release rate of medicine
• Tubes release potent drugs very slowly while chambers release at fairly fast rates
• Cell chambers can be used to produce compounds, such as insulin, inside the body
http://www.nature.com/nbt/journal/v21/n10/full/nbt876.html
Drug-releasing chamber
Truly Smart Medicine?• An “ideal” drug delivery system would be able to
determine when and if a dose was needed and would deliver it automatically
• We’re not there yet, but we’re getting closer every day!
Works Cited• http://www.math.uci.edu/~cristini/publications/nanochap.pdf• http://circ.ahajournals.org/cgi/content/full/107/8/1092• http://nano.cancer.gov/resource_center/nano_critical.asp• http://www.nature.com/nbt/journal/v21/n10/full/nbt876.html• http://www2.mdanderson.org/depts/oncolog/articles/03/7-8-julaug/7-8-03
-1.html
• http://www.economist.com/printedition/displayStory.cfm?Story_ID=916725
• http://www.nature.com/materials/nanozone/news/010927/portal/011004-2.html
• http://health.howstuffworks.com/aspirin3.htm
Works Cited (cont.)• http://courses.csusm.edu/biol356bm/Powerpoints/
drug_delivery_nano.pdf• http://leeexplore.leee.org/eil5/9589/30307/01392308.pdf?
arnumber=1392308• http://www.pnas.org/cgi/content/full/102/25/8860• http://www.sciencedaily.com/releases/
2005/06/050621074514.htm• Nanoscale Technology in Biological Systems Greco, Ralph S.