There have been a number of attempts to create artificial blood, but most so far have some drawbacks, e.g. risk of heart attacks in the patients, usually trauma cases, that receive such transfusions.

Researchers at the University of Pennsylvania have, however, now succeeded in constructing an artificial protein from scratch that is capable of carrying and delivering oxygen in the body and that is resistant to ingress by water which causes release of oxygen that can cause cellular damage.

Unlike existing blood substitutes, which are usually constructed from modified natural haemoglobin the Pennsylvania team used three amino acids to make a four-helix columnar candelabra-shaped protein structure containing a heme structure similar to the active part of haemoglobin capable of opening and closing to receive and deliver oxygen without letting water in.

While further work is required to ensure that the new protein can hold on to oxygen for long enough to be useful, and to ensure that it can work in a cellular environment and is non-toxic, the research represents a notable step in protein design

Source: MIT Technology Review

Posted: March 30th, 2009 under Chemistry, Nanomedicine.
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Using the world’s most advanced electron microscope, Eindhoven University of Technology researchers have, for the first time, captured high-resolution images of the earliest stages of bone formation. Utilizing the FEI Company’s cryoTitan microscope they imaged small clusters of calcium carbonate and showed that clusters consisting of around ten ions formed the basis for the process resulting in nucleation into larger, unstructured nanoparticles with an average diameter of around thirty nanometers through which the crystalline biominerals are formed.

The work, published in Science magazine offers increased understanding of bone, tooth and shell formation and could have important implications for creating industrial biomimetic materials.

Source: Nanowerk

Posted: March 13th, 2009 under Advanced materials, Advanced medtech, Nanomedicine.
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Researchers at the Cidetec-IK4 Research Centre at San Sebastian in Spain have developed a new type of electrochemical nanobiosensor capable of detecting mutations in DNA much more rapidly than before. The sensor technology also offers the possibility to be extended to the detection of other types of molecule.

The nanobiosensor comprises a nanotransistor, the cable of which is a carbon nanotube modified by a polymer that enables DNA to anchor. High selectivity can be achieved without the need to modify the DNA and the sensor is capable of detecting sequences, such as those implicated in particular genetic diseases directly.

Source: Basque Research

Journal reference: Nano Letters, 2009; 9 (2): 530

Cidetec-IK4

Posted: March 10th, 2009 under Advanced medtech, Nanomedicine, Nanotechnology.
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Researchers at Sandia National Laboratories, Livermore, California have succeeded in developing a device based on carbon nanotubes that can detect the entire visible spectrum of light and which may find potential uses in artificial retinas and other light gathering applications such as solar cells and miniature cameras for use in low light conditions. Earlier attempts at similar devices were only able to detect specific wavelengths.

The device utilizes carbon nanotubes decorated with three different types of chromophores, which are molecules that change shape in response to particular wavelengths of light… in the case of the Sandia research red, green and blue wavelengths. This change in shape alters the orientation of the chromophores in relation to the nanotube which, in turn, alters the conductivity of the nanotube to give a signal that can be measured. Because of their size, the nanotubes have intrinsically high resolution… around the diameter of each nanotube or 1nm.

The researchers believe that the process of manufacturing such devices could be scaled up and are also working on versions of the device that can detect infrared light, and which are more sensitive.

Source: MIT Technical Review

Posted: March 10th, 2009 under Advanced materials, Physics, Advanced medtech, Nanomedicine, Nanotechnology.
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Recent research at the US Department of Energy’s Pacific Northwest National Laboratory (PNNL) in Richland, Washington, provides further evidence to suggest that total surface area rather than size, mass or number of particles may be the most appropriate metric in relation to the toxicity of some types of nanoparticles. This supports similar conclusions reached by the EC Scientific Committee in its Opinion on the appropriateness of existing risk assessment methodologies published on 29 March 2007.

Being aware of the difficulties in agreeing on the most relevant nanoparticle dose unit to use to measure toxicity, Brian Thrall and colleagues at PNNL studied the dose of amorphous silica nanoparticles required to cause a biological response. Using particle number or mass as a dose metric their results were inconsistent but by calculating the total surface area they were able to predict a biological response which appeared also, in the study, to vary little according to the size of the nanoparticles.

Source: Pacific Northwest National Laboratory

Posted: March 4th, 2009 under Safety and risk, Nanomedicine.
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