he curious jelly-like properties of hydrogels have made them widely useful for medical implants such as contact lenses, among other applications. In March, researchers reported the creation of a potentially even more useful self-healing hydrogel that repairs itself in seconds upon simply changing the surrounding pH (Proc. Nat. Acad. Sci., doi: 10.1073/pnas.1201122109). The trick was to arm the hydrogel with dangling side chains capable of interlocking separate pieces of hydrogel by hydrogen bonding, the researchers at the University of California, San Diego, US, reported.
‘The dangling bonds were designed to have an optimal length to mediate hydrogen bonds across two hydrogel pieces like interlocking fingers in a clasped hand,’ said report author Shyni Varghese. However, they were not so long that they collapsed back into the hydrogel, she added. The group coated various surfaces with the resulting hydrogel and then damaged them with cracks, which healed rapidly on exposure to low pH solutions and over a range of temperatures, light and humidity conditions. New applications for self-healing hydrogels could include drug delivery devices.
granted by US regulators in early summer 2012 – a development that could pave the way for more drugs produced in plants. The drug, taligluciferase alfa (Elelyso),
Drug grown in carrots T
he first approval for a drug grown in genetically engineered plant cells was
replaces an enzyme lacking in people with type 1 Gaucher’s disease, a rare genetic disorder that leads to the accumulation of lipids and fats inside cells (C&I, 2012, 6, 9).
Pfizer/Protalix’s Elelyso fared at least as well as another commercially available enzyme replacement therapy in clinical trials. It is the first approved plant-cell
expressed drug derived from Protalix’s proprietary manufacturing system, ProCellEx. The company is also developing another protein produced in carrot cells to treat another enzyme-related disorder, Fabry disease.
hose afflicted with the seasonal curse of severe hay fever may be able to look forward to a time when they can go outdoors without fear of an attack, judging by the results of new vaccine trials reported this summer (C&I, 2012, 7, 15). The vaccine’s developers at Vienna, Austria-based biopharma company Biomay claim that it will offer a big improvement
Vaccine for hay fever T
over current immunotherapy approaches, used where antihistamines or nasal steroids fail, as it will only require three to four annual injections. Conventional immunotherapy typically requires 60 to 100 injections. The vaccine, BM32, is made by fusing B-cell peptides from the grass pollen allergen with an immunogenic carrier protein
2005. However, it was not until September 2012 that the same group finally obtained enough evidence to support their claims to name the element. The new results, produced in experiments at the RIKEN Radioisotope Beam Factory (RIBF) near Tokyo, identify the element conclusively through connections to well-known daughter nuclides formed on decay of element 113 (Journal of Physical Society of Japan, doi: 10.1143/JPSJ.81.103201). While the group’s earlier work had observed only four decay events followed by spontaneous decay of dubnium-262 (element 105), the new
34 Chemistry&Industry • November 2012
Element 113 nailed R
esearchers in Japan got the first fleeting glimpses of element 113 back in 2004 and
from a virus. In a Phase 2a study, patients receiving three doses of either 20µg or 40µg of BM32 over two months showed a significant reduction in their nasal symptoms and a boost in immunoglobulin antibody levels, it was claimed. Lindsey McManus of Allergy UK described the therapy as ‘a very exciting prospect.’
data indicate that dubnium decayed into lawrencium-258 (element 103) and finally into mendelevium-254 (element 101). It was this alpha decay to lawrencium that provided proof of element 113 as the origin of the chain. To carry out the experiment, RIKEN’s Kosuke Morita and colleagues accelerated zinc ions towards a thin layer of bismuth in a linear accelerator to produce the heavy ion, and then tracked the ensuing decay processes. The group had been looking for evidence of element-113 for over nine years, Morita commented. ‘At last we have it. It feels like a great weight has been lifted from our shoulders.’