Posts Tagged ‘chemistry’


Japan Takes the 2011 Ig Nobel Chemistry Prize for Wasabi Fire Alarm

October 19, 2011

Earlier this month, an annual tradition continued at Harvard’s Sanders Theater, where the science/humor magazine Annals of Improbable Research handed out its Ig Nobel Awards, in recognition of achievements “that make people laugh, and then make them think.”

The Chemistry prize at the 21st First Annual (sic) awards ceremony went to a Japanese research team, led by Asst. Professor Makoto Imai of the Shiga University of Medical Science and Dr. Junichi Murakami of Biwako Hospital in Shiga Prefecture, for their work in developing a “wasabi-based fire alarm.” While the work may sound a bit silly at first blush (as does the work of many of the other prize recipients), I think it’s worth taking a closer look to see the motivation behind his research and the actual benefits it has led to.

Prof. Imai holds up his Ig Nobel Prize

Via the Boston Herald

Imai and the rest of the team receiving their prize at the 2011 Ig Nobel ceremony at Sanders Theater, Harvard. (set to skip ahead to the Chemistry Prize, but the whole ceremony is well worth watching)

This project first began in 2000, when Prof. Imai looked into the question of how to make a fire alarm that can be reliably detected by the hearing impaired. The elderly make up over 50% of deaths in house fires in Japan, and it has been hypothesized that inability to hear traditional smoke alarms may contribute to this figure. Standard alarms using loud sirens would of course go unnoticed, and flashing lights (often included with the alarms used in newer apartment buildings) were often found to be completely ineffective at waking up sleeping residents. This was when Imai and his team decided to start looking at less conventional directions.

Inside the wasabi smoke alarm

Vibrations had been tried, but this approach suffers from a number of practical problems, not least of which was the issue of how to rig an entire apartment to vibrate strongly enough that it could be reliably noticed. Even when restricted to just making the bed shake, anyone who’s used a vibrating cell phone knows how easy it is to simply not notice it. To effectively grab attention, Imai and his co-researchers decided to tap into our sense of smell.

With the backing of the Seems company, a research firm focusing on fragrance-based sensors and other medical tools, the team experimented with with a wide range of aromatic chemicals, ranging from the pleasant to the putrid. But according to Imai, even some of the most revolting of smells seemed to have little effect: “We tried a rotten egg smell, but subjects didn’t wake up.”

Imai (L) and Murakami with their award

Via Chuunichi News

The aroma with the most success turned out to be allyl isothiocyanate, an irritant responsible for the  pungent taste of wasabi, horseradish and varieties of mustard. In nature, the plants produce the chemical as a defense against herbivores, but for Imai’s team its nose- and throat-stinging properties made it ideal for rousing sleepers in the event of fire.

In 2006, clinical tests were started at Biwako Hosiptal, where 31 volunteers were repeatedly allowed to go to sleep, then had the allyl isothiocyanate aerosol sprayed into their rooms as researchers tested which concentrations produced the most reliable results (the chemical can also be an eye irritant much like tear gas or pepper spray, so presumably the team didn’t want to use such a high concentration that subjects were unable to find their way out once they’d woken up). A spray of 5-20ppm was found to wake up nearly every test subject within 2 minutes.

Diagram from Imai's patent for the alarm system

The system has already been installed in a number of facilities for the deaf in Japan, and it is scheduled for commercial release within the next two years.

As a side note, Japanese researchers and inventors have been regulars at the Ig Nobel ceremonies almost since they began, so I’m planning on writing a series of articles highlighting each of their accomplishments. If I don’t, leave a note in the comments telling me to move my butt.

Additional reference:

Annals of Improbable Research, Ig Nobel Winners List

Patent for the wasabi smoke detector

NTV News24 – “イグ・ノーベル賞の今井講師が喜びの会見” (with embedded video) 2011 Oct 4

Chuunichi News – “「いつかノーベル賞を」 イグ・ノーベル賞受賞の今井氏ら会見” 2011 Oct 5

Kyodo News – “Japanese team wins Ig Nobel award for ‘wasabi alarm’” 2011 Sep 30:

MSN/Sankei News – “イグ・ノーベル賞の滋賀医科大今井講師 帰国会見で感謝” 2011 Oct 5:

Seems Corporation homepage


RIKEN Develops Transparent Mice

September 7, 2011

Researchers at the natural sciences institute RIKEN announced in the journal Nature Neuroscience that they had succeeded in developing a reagent that turns organic matter almost fully transparent. This breakthrough opens up new possibilities for far more detailed analysis of how the complex networks within our organs function.

Right: a preserved mouse embryo that has been placed in standard saline. Left: a preserved mouse embryo that has been incubated for two weeks in a solution of  sca/eA2, the reagent developed by the RIKEN team.

For biologists and medical researchers, mapping out the microscopic structures of organs is a problematic endeavor: because the majority of our organs (and those of other animals) are opaque, viewing them under a microscope requires slicing them down to just a millimeter thick. While this allows one to view the inner structures of the cells, it makes it impossible to directly observe the larger networks of cells, which have complex 3-D structures. In fact, intricate mapping work such as tracing the circuitry of the brain still has to be done largely by hand.

3-D imaging of neurons and their interconnections inside the brain of a mouse treated with sca/eA2

In his published report, researcher Atsushi Miyawaki describes how he and his team developed sca/eA2, a reagent that turns organs transparent without disrupting their shape or cohesion, and without affecting the function of genetically encoded fluorescent proteins frequently used in cell research. Already, Miyawaki’s team has used sca/eA2 to image the brains of mice embryos to a much greater depth than was previously possible, revealing a surprising level of detail in the networks of neurons, as well as allowing them to visualize the connections between the brain’s hemispheres.

3-D image of the connections between the right and left halves of a mouse brain, made visible with the sca/eA2 reagent.

One big advantage of sca/eA2 is the price tag. The reagent is made from three simple ingredients readily available in any laboratory: urea, Triton-X, a detergent used to make cell membranes more permeable, and glycerol. This puts it easily within the budget of almost any research group, opening up a wealth of new imaging possibilities. “Our current experiments are focused on the mouse brain, but applications are neither limited to mice, nor to the brain,” says Miyawaki. “We envision using Sca/eA2 on other organs such as the heart, muscles and kidneys, and on tissues from primate and human biopsy samples.”

3-D visualization of mouse neural stem cells and blood vessels.

Currently, sca/eA2 only works on dead tissue, but Miyawaki and his team are already looking into changing that. “We are currently investigating another, milder candidate reagent which would allow us to study live tissue in the same way, at somewhat lower levels of transparency. This would open the door to experiments that have simply never been possible before.”

P.S. A lot of articles, blogs and aggregators have been making a big deal of the fact that sca/eA2 uses urea (“How do you turn a mouse brain transparent? Pee on it!”). Grow up guys. If it bothers you that much, then you really don’t want to know what goes into diesel emission treatments, dish soap, cigarettes or cattle feed.