Cellular Visions: The Inner Life of a Cell

Hat-tip to StudioDaily.com for helping publicize a remarkable animation of life on the nano scale:

Created by XVIVO, a scientific animation company near Hartford, CT, the animation illustrates unseen molecular mechanisms and the ones they trigger, specifically how white blood cells sense and respond to their surroundings and external stimuli.

The StudioDaily.com page referenced above has links to high-definition versions of this remarkable video. For blog purposes it was gratifying to find the whole thing posted on YouTube. The conception and content by were by Alain Viel and Robert A. Lue, and the animation was composed by John Liebler/XVIVO. See http://multimedia.mcb.harvard.edu/ for more information.

Virus 'hybrids' can act as nanoscale memory devices

NewScientistTech reports on a fascinating mash-up of viruses and quantum dots (nanoscale spheroids of selected materials including semiconductor atoms which yield remarkable electro-optic properties due to quantum containment effects). This research was performed at the University of California, Riverside, and published in a paper entitled "Microscale memory characteristics of virus-quantum dot hybrids" in Applied Physics Letters.

A new type of memory device has been made by researchers in the US and Italy by attaching individual viruses to tiny specks of semiconducting material called quantum dots. The "hybrid" material could be used to develop biocompatible electronics and offer a cheap and simple way to make high-density memory chips, the researchers say... "Interactions between organic and inorganic particles are quite fascinating," team leader [Mihri] Ozkan told New Scientist. "In our case, finding the memory effect was quite unexpected because each nanoparticle does not have any memory characteristics on its own, but only when connected as a hybrid."
Non-volatile memory
Ozkan and co-workers began by depositing cosahedral cowpea mosaic viruses (CPMV) on quantum dots (made of cadmium selenide and zinc sulphide) using different binding sites on the virus' capsid, or outer shell. CPMV, a plant virus that is harmless to humans, is about 30 nanometres across and consists of a capsid with an RNA core. Next, the researchers embedded the hybrids into a polymer matrix and sandwiched them between two conducting electrodes for testing. They found that each hybrid unit can be operated as a memory device with conductive states that can be switched between high and low, corresponding to a 1 and a 0, by applying a low voltage. These states are "non-volatile", meaning data is stored even when the power is switched off.

Remarkable.

DNA Replication, up close and personal

This animation illuminates how the molecular basis of life is understood through today's research, with profound implications for medicine. Blogger "Xantox" explains of this video from The Walter & Eliza Hall Institute in Australia,

Using computer animation based on molecular research it is possible to see how DNA is actually copied in living cells. This animation shows the “assembly line” of biochemical machines which pull apart the DNA double helix and output a copy of each strand. The DNA to be copied enters the whirling blue molecular machine, called helicase, which spins it as fast as a jet engine as it unwinds the double helix into two strands. One strand is copied continuously, and can be seen spooling off on the other side. Things are not so simple for the other strand, because it must be copied backwards, so it is drawn out repeatedly in loops and copied one section at a time. The end result is two new DNA molecules.

What you see here is occurring countless billions of times in your body right now. It gets even more wondrous: research by Steven Block and his students and post-docs at Stanford University show that processes like this essentially edit their own work. The discovery mechanism for all this is the astonishing nanotech tool of optical tweezers. See my article on that from Biophotonics International here.

Old Spice smells like... a cure

Curcumin is worth googling about. It may well be the next wonder drug. Its nanotech connection is in some research being performed at Johns Hopkins:

Anirban Maitra, a professor of pathology and oncology at Johns Hopkins, and his collaborators in Delhi--including his father, Amarnath Maitra, a professor of chemistry--used special polymers to synthesize tiny nanoparticles about 50 nanometers in diameter. The particles have hydrophobic interiors and hydrophilic exteriors. The hydrophobic component holds the curcumin, while the hydrophilic exteriors make the particles soluble. This way, they can pass easily from the gut to the bloodstream. Once in the blood, the curcumin leaks out as the polymers slowly degrade.

This is a fine example of how nanomaterial technologies can provide new properties and facilitate new promise, even for something as venerable as curry spice.