11-01 :: December 2010 / January 2011

nanotimes News in Brief

Thanks to Oplon of Israel, there may soon be rejoicing among acne sufferers. The three-year-old medical materials company in Rehovot in central Israel has come up with a unique patch that radiates an ‘energy field‘ said to be capable of knocking out acne for good. http://israel21c.org/201011148498/health/knocking- out-acne-with-a-plastic-patch

Massachusetts General Hospital (MGH, USA) investigators have developed a novel system for delivery of growth factors to chronic wounds such as pressure sores and diabetic foot ulcers. The team from the MGH Center for Engineering in Medicine (CEM) reports fabricating nanospheres containing keratinocyte growth factor (KGF), a protein known to play an important role in wound healing, fused with elastin-like peptides. When suspended in a fibrin gel, these nanoparticles improved the healing of deep skin wounds in diabetic mice.

“It is quite amazing how just one dose of the fusi- on protein was enough to induce significant tissue regeneration in two weeks,” says the paper‘s lead author Piyush Koria, PhD, formerly a postdoctoral fellow at the MGH-CEM and now at the University of South Florida. “Previous reports have suggested that KGF can help heal chronic wounds. But in most studies the growth factor was applied to the surface of the wound, limiting its availability to deeper tissues and requiring repeat applications to produce any clinical benefit. Using large quantities of growth factor would make this therapy extremely expensive. Our work circumvents these limitations by more efficiently delivering KFG throughout the wound to stimulate tissue regeneration.”

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The authors describe developing a fusion protein from recombinant KGF and elastin-like-peptides, which are major constituents of skin and other con- nective tissues. Laboratory experiments showed that the fusion protein retained the wound-healing pro- perties of both elastin and KGF and that it rapidly and efficiently self-assembled into nanoparticles in response to a simple increase in temperature. When applied to deep skin wounds in genetically diabe- tic mice, the nanoparticles accelerated healing by stimulating the formation of both surface epithelial tissue and thick fibrous connective tissue.

Piyush Koria, Hiroshi Yagi, Yuko Kitagawa, Zaki Megeed, Yaakov Nahmias, Robert Sheridan, and Martin L. Yar- mush: Self-assembling elastin-like peptides growth fac- tor chimeric nanoparticles for the treatment of chronic wounds, In: PNAS, Vol. 108 no. 3, January 18, 2011, Pages 1034-1039, DOI:10.1073/pnas.1009881108: http://dx.doi.org/10.1073/pnas.1009881108

Northwestern University researchers have deve- loped a new technique for rapidly prototyping nanoscale devices and structures that is so inex- pensive the “print head” can be thrown away when done. Hard-tip, soft-spring lithography (HSL) rolls into one method the best of scanning-probe litho- graphy – high resolution – and the best of polymer pen lithography – low cost and easy implementa- tion. HSL could be used in the areas of electronics (electronic circuits), medical diagnostics (gene chips and arrays of biomolecules) and pharmaceu- ticals (arrays for screening drug candidates), among others.

To demonstrate the method‘s capabilities, the researchers duplicated the pyramid on the U.S.