11-01 :: December 2010 / January 2011

nanotimes News in Brief

Researchers from MIT (USA), Rutgers University (USA), University of South Florida (USA), Massachu- setts General Hospital (USA), Harvard Medical School (USA), Hebrew University of Jerusalem (Israel), Keio University School of Medicine (Japan), demonstrate the fabrication of a fusion protein comprising of elastin-like peptides and KGF. This fusion protein retains the performance characteri- stics of keratinocyte growth factor (KGF) and elastin as evidenced by its enhancement of keratinocyte and fibroblast proliferation. It also preserved the characteristic elastin-like peptides inverse phase transitioning allowing the recombinant protein to be expressed in bacterial hosts (such as Escherichia coli) and purified rapidly and easily using inverse temperature cycling. The fusion protein self-as- sembled into nanoparticles at physiological tem- peratures. When applied to full thickness, wounds in Leprdb diabetic mice these particles enhanced reepithelialization and granulation, by 2- and 3-fold respectively, when compared to the controls. The data strongly suggests that these self-assembled nanoparticles may be beneficial in the treatment of chronic wounds resulting from diabetes or other underlying circulatory conditions.

Piyush Koriaa, Hiroshi Yagia, Yuko Kitagawae, Zaki Me- geeda, Yaakov Nahmiasa, Robert Sheridana, and Martin L. Yarmush: Self-assembling elastin-like peptides growth factor chimeric nanoparticles for the treatment of chro- nic wounds, In: PNAS Early Edition, December 30, 2010, DOI:10.1073/pnas.1009881108: http://dx.doi.org/10.1073/pnas.1009881108

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CEA-Leti announced the first infrared imaging array in the 8-10µm band capable of returning an image with a record-breaking minimum tempera- ture difference, or thermal resolution, of 1 to 2mK at ambient temperature and with traditional image cadences of 25-50 Hertz.

Leti also created an infrared detection array by linking an innovative reading circuit, manufactured using CMOS-silicon technology, to an array of Hg- CdTe infrared detectors. Designed for defense and security applications, the HgCdTe array has a format of 320x256 and a pitch of 25µm. The array achie- ved ultimate sensitivity of close to one-thousandth of a degree Kelvin at an operating temperature of 77K. It represents 10-20x increase in sensitivity compared with what is normally possible under the same observation conditions with conventional components.

To obtain this extremely high sensitivity, CEA-Leti designed and produced a special silicon reading cir- cuit with a 0.18µm CMOS die, involving an analog- to-digital conversion at each elementary detection point with a pitch of 25µm.

The analogue-to-digital conversion is based on the counting of charge packets given off by the detec- tor. An equivalent stored charge of 3 giga-electrons can be obtained. This reading circuit, which is noise-optimised, thus makes it possible to achieve a level of sensitivity never before obtained on a com- ponent of this class.

http://www.leti.fr