Bio-Based Ideas

With my thesis defense coming up this Monday, I really did not have as much time to share all the interesting things I came across lately. But I did not want to miss the chance to make a quick note to myself and the readers of this site of an interesting paper, titled "DNA-based programming of quantum dot valency, self-assembly and luminescence" just published in Nature Nanotechnology . Grigory Tikhomirov et al. report "the self-assembly of quantum dot complexes using cadmium telluride nanocrystals capped with specific sequences of DNA. Quantum dots with between one and five DNA-based binding sites are synthesized and then used as building blocks to create a variety of rationally designed assemblies, including cross-shaped complexes containing three different types of dots...Through changes in pH, the conformation of the complexes can also be reversibly switched, turning on and off the transfer of energy between the constituent quantum dots." In other w

It's been a while again since I last posted here. Writing my thesis and preparing for the actual defense in July are taking most of my time. However, I wanted to at least share an interesting idea I came across in the last couple of months before this month is over. And so today, I'll write about the artificial leaf which Professor Nocera at MIT was researching. It's been all over the science news: an alloy made of nickel and cobalt acts as a catalyst to split water into hydrogen and oxygen similar to what plant leafs do when they perform photosynthesis. After the coolness of the words "artificial leafs" wore off, I started to wonder what is so special about an artificial leaf. After all, doesn't an artificial leaf just do electrolysis ? Couldn't I just achieve the same by connecting solar panels to a container with water and two electrodes? Apparently, the answer is yes and no. By applying a current to water, electrolysis could indeed be performed p

Prolog: It has been a while since last I discussed a scientific journal paper. The following post is based on a paper published in the American Chemical Society NANO Journal (Vol.2, No. 10, pp 2103-2112) with the title “Metabolic Insertion of Nanostructured TiO2 into the Patterned Biosilica of the Diatom Pinnulario sp. by a Two-Stage Bioreactor Culvtivation Process”. What have they done? The Rorrer lab is a nanotechnology/biotechnology engineering lab. They manipulate various microorganisms so that the microorganisms produce substances that are of use to human kind. Their latest series of publications has focused on diatoms which are single-celled algae that are able to make silica shells with very intricate patterns (see below). The Rorrer lab has a significant body of work inducing a particular diatom by the name of Pinnulario sp . to incorporate optoelectronic substances into its frustules (outer shells) that it normally would not. Optoelectronic substances can transform, tra