Could Nanotechnology Make An Average Candy Into Health Food?

European food companies already use nanotechnology in consumer products, but few volunteer the information to consumers, said Dutch food scientist Frans Kampers.


He is among the panelists gathered in Chicago for the American Association for the Advancement of Science annual meeting symposium “From Donuts to Drugs: Nano-Biotechnology Evolution or Revolution.”

Kampers from Wageningen University and Research Center in the Netherlands will take a look at food science issues in his presentation, “What Nanotechnology Can Do for Your Average Donut.”

“All of us as scientists are being impacted by nano-bioscience and there are many issues. The interdisciplinary aspect is just one of them,” said Rod Hill, a University of Idaho professor and symposium organizer.

The panel includes two graduate students, Jessica Koehne of the University of California, Davis, and Kristina Kriegel of the University of Massachusetts, are working on projects combining, nanotechnology with biology and chemistry.

“On the food side there is greater public resistance to nanomaterials and nanotechnology in food whereas on the biomedical side there is greater public acceptance or less recalcitrance,” Hill added.

His focus on applications, products and processes, and on sensors useful for in food safety and food quality monitoring and in packaging, reflects the wide range of nanotechnology’s use in the food industry, Kampers said.

“The problem I always face is that people do not understand what we are doing with nanotechnology and food,” Kampers said. “Everyone has this vision of nanotechnology being nanoparticles and nanoparticles being risky, so they are very afraid that nanoparticles in food will have an adverse effect on health.”

The promise of nanotechnology, the Dutch scientist said, is that it could allow re-engineering ingredients to bring healthy nutrients more efficiently to the body while allowing less-desirable components to pass on through.

European food scientists use nanotechnology to create structures in foods that can deliver nutrients to specific locations in the body for the most beneficial effects, Kampers said.

“We are basically creating nanostructures in food that are designed to fall apart in your body because of digestion so in the end there will not be nanoparticles,” Kampers said.

He said there are some researchers studying applications of persistent nanoparticles in food and packaging that he believes could present risks. Use of metal, usually silver, nanoparticles in packaging to slow spoilage could move from the packaging material into the food itself.

“The persistent metal or metal oxide nanoparticles could move into the bloodstream, and research has shown they can migrate into cells or in some cases even into the nucleus of cells,” Kampers said.

“These are the more controversial applications of nanotechnology,” Kampers added. “More research is necessary to understand the kinetics and dynamics of these particles before large-scale applications in food are developed. At the moment, these types of nanoparticles are rarely used in food products.”

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Chemists Create Bipedal, Autonomous DNA Walker

ScienceDaily (Apr. 6, 2009) — Chemists at New York University and Harvard University have created a bipedal, autonomous DNA “walker” that can mimic a cell’s transportation system. The device, which marks a step toward more complex synthetic molecular motor systems, is described in the most recent issue of the journal Science.

dna

Two fundamental components of life’s building blocks are DNA, which encodes instructions for making proteins, and motor proteins, such as kinesin, which are part of a cell’s transportation system. In nature, single strands of DNA—each containing four molecules, or bases, attached to backbone—self-assemble to form a double helix when their bases match up. Kinesin is a molecular motor that carries various cargoes from one place in the cell to another. Scientists have sought to re-create this capability by building DNA walkers. Earlier versions of walkers, which move along a track of DNA, did not function autonomously, thereby requiring intervention at each step. A challenge these previous devices faced was coordinating the movement of the walker’s legs so they could move in a synchronized fashion without falling off the track. To create a walker that could move on its own, the NYU and Harvard researchers employed two DNA “fuel strands.” These fuel strands push the walker (blue) along a track of DNA, thereby allowing the walker and the fuel strands to function as a catalytic unit. The forward progress of the system is driven by the fact that more base pairs are formed every step—a process that creates the energy necessary for movement. As the walker moves along the DNA track, it forms base pairs. Simultaneously, the fuel strands move the walker along by binding to the track and then releasing the walker’s legs, thereby allowing the walker to take “steps”. The track’s length is 49 nanometers—if the track was one meter long, an actual meter, enlarged proportionally, would be the approximate diameter of the earth. For a video demonstration of the walker, go to http://www.nyu.edu/public.affairs/videos/qtime/biped_movie.mov. The walker was created in the laboratory of NYU Chemistry Professor Nadrian Seeman, one of the article’s co-authors. The paper’s other authors were Tosan Omabegho, a doctoral candidate at Harvard’s School of Engineering and Applied Sciences, and Ruojie Sha, a senior research associate in the NYU Chemistry Department.

Cientists Developed a New Way To Split Water Into Hydrogen And Oxygen

The design of efficient systems for splitting water into hydrogen and oxygen, driven by sunlight is among the most important challenges facing science today, underpinning the long term potential of hydrogen as a clean, sustainable fuel. But man-made systems that exist today are very inefficient and often require additional use of sacrificial chemical agents. In this context, it is important to establish new mechanisms by which water splitting can take place.

water2

Now, a unique approach developed by Prof. David Milstein and colleagues of the Weizmann Institute’s Organic Chemistry Department, provides important steps in overcoming this challenge. During this work, the team demonstrated a new mode of bond generation between oxygen atoms and even defined the mechanism by which it takes place. In fact, it is the generation of oxygen gas by the formation of a bond between two oxygen atoms originating from water molecules that proves to be the bottleneck in the water splitting process. Their results have recently been published in Science. Nature, by taking a different path, has evolved a very efficient process: photosynthesis – carried out by plants – the source of all oxygen on Earth. Although there has been significant progress towards the understanding of photosynthesis, just how this system functions remains unclear; vast worldwide efforts have been devoted to the development of artificial photosynthetic systems based on metal complexes that serve as catalysts, with little success. (A catalyst is a substance that is able to increase the rate of a chemical reaction without getting used up.) The new approach that the Weizmann team has recently devised is divided into a sequence of reactions, which leads to the liberation of hydrogen and oxygen in consecutive thermal- and light-driven steps, mediated by a unique ingredient – a special metal complex that Milstein’s team designed in previous studies. Moreover, the one that they designed – a metal complex of the element ruthenium – is a ‘smart’ complex in which the metal center and the organic part attached to it cooperate in the cleavage of the water molecule. The team found that upon mixing this complex with water the bonds between the hydrogen and oxygen atoms break, with one hydrogen atom ending up binding to its organic part, while the remaining hydrogen and oxygen atoms (OH group) bind to its metal center. This modified version of the complex provides the basis for the next stage of the process: the ‘heat stage.’ When the water solution is heated to 100 degrees C, hydrogen gas is released from the complex – a potential source of clean fuel – and another OH group is added to the metal center. ‘But the most interesting part is the third ‘light stage,’’ says Milstein. ‘When we exposed this third complex to light at room temperature, not only was oxygen gas produced, but the metal complex also reverted back to its original state, which could be recycled for use in further reactions.’ These results are even more remarkable considering that the generation of a bond between two oxygen atoms promoted by a man-made metal complex is a very rare event, and it has been unclear how it can take place. Yet Milstein and his team have also succeeded in identifying an unprecedented mechanism for such a process. Additional experiments have indicated that during the third stage, light provides the energy required to cause the two OH groups to get together to form hydrogen peroxide (H2O2), which quickly breaks up into oxygen and water. ‘Because hydrogen peroxide is considered a relatively unstable molecule, scientists have always disregarded this step, deeming it implausible; but we have shown otherwise,’ says Milstein. Moreover, the team has provided evidence showing that the bond between the two oxygen atoms is generated within a single molecule – not between oxygen atoms residing on separate molecules, as commonly believed – and it comes from a single metal center. Discovery of an efficient artificial catalyst for the sunlight-driven splitting of water into oxygen and hydrogen is a major goal of renewable clean energy research. So far, Milstein’s team has demonstrated a mechanism for the formation of hydrogen and oxygen from water, without the need for sacrificial chemical agents, through individual steps, using light. For their next study, they plan to combine these stages to create an efficient catalytic system, bringing those in the field of alternative energy an important step closer to realizing this goal.

Journal reference:

  1. Stephan W. Kohl, Lev Weiner, Leonid Schwartsburd, Leonid Konstantinovski, Linda J. W. Shimon, Yehoshoa Ben-David, Mark A. Iron, and David Milstein. Consecutive Thermal H2 and Light-Induced O2 Evolution from Water Promoted by a Metal Complex. Science, 2009; 324 (5923): 74 DOI: 10.1126/science.1168600

Gold particles deliver more than just glitter

Nanoparticles could carry drugs to treat cancer, or other disease?

Anne Trafton, News Office
December 30, 2008

Using tiny gold particles and infrared light, MIT researchers have developed a drug-delivery system that allows multiple drugs to be released in a controlled fashion. Such a system could one day be used to provide more control when battling diseases commonly treated with more than one drug, according to the researchers. “With a lot of diseases, especially cancer and AIDS, you get a synergistic effect with more than one drug,” said Kimberly Hamad-Schifferli, assistant professor of biological and mechanical engineering and senior author of a paper on the work that recently appeared in the journal ACS Nano. Delivery devices already exist that can release two drugs, but the timing of the release must be built into the device — it cannot be controlled from outside the body. The new system is controlled externally and theoretically could deliver up to three or four drugs. The new technique takes advantage of the fact that when gold nanoparticles are exposed to infrared light, they melt and release drug payloads attached to their surfaces. Nanoparticles of different shapes respond to different infrared wavelengths, so “just by controlling the infrared wavelength, we can choose the release time” for each drug, said Andy Wijaya, graduate student in chemical engineering and lead author of the paper. The team built two different shapes of nanoparticles, which they call “nanobones” and “nanocapsules.” Nanobones melt at light wavelengths of 1,100 nanometers, and nanocapsules at 800 nanometers. In the ACS Nano study, the researchers tested the particles with a payload of DNA. Each nanoparticle can carry hundreds of strands of DNA, and could also be engineered to transport other types of drugs. In theory, up to four different-shaped particles could be developed, each releasing its payload at different wavelengths.

nanoparticles of gold

The top image shows a mixture of gold nanoparticles. The longer particles are called nanobones, and the smaller are nanocapsules. Bottom left: After the nanoparticles are hit with 800 nanometer wavelength infrared light, the nanocapsules melt and release their payload. Nanobones remain intact. Right: After the nanoparticles are hit with 1100 nanometer wavelength infrared light, the nanobones melt and release their payload. Nanocapsules remain intact. Image / Andy Wijaya

Journey to France

I’m back my friends, not to talk about the world crash or the financial disease but to talk about the most free feeling to go on a journey alone. This time I went to France, in fact because of a scientific work that I’ve to do till 13th April, but I allways take some time to discover the new World.
The history starts in the plane when I had arrived Paris Orly (airport), I had to wait a few minutes inside the plane and then a Portuguese guy start to complaint: “Open the fucking door, god dammit!”, then the girl from the board said: “Please, be quit and wait a few more minutes”, and then the guy conclude: “Call to the Fireman mam, they will open the fuckin door! I’ve to take another plane and I’ve a meeting with a girl, and actually I’ve a reservation in the restaurant too! Open the fuk’in door…”
So, nice way to start in a new place! I felt like if I was in home. 😉
Then, I walked outside from the airport and I feet for the first time the land of the beginning of the Sun, Paris. Nothing special actually, but I didn’t had time to explore Paris and I was in the suburbs, so I should not take false conclusions. By the way my concern was, to take the BUS from Orly to Pont de Rungis… I forgot to said that my French is bad, and I had to ask for some informations. I made the first attempt in English… and what was my amazement, the girl talked with me very well in English too! Lucky day…
I arrived Pont de Rungis, and there I had to take the RER C to Gare d’Austerlitz. I went to the reception and ask for a ticket… the guy said to me: ” Je ne comprende, qu’est-ce que vous dites?” and I badly said: “Je… veux… acheter un… billet, si’l vous plait!”, and he replies: “Oh oui monsieur, un billet pour Austerlitz, je va donner maintenant l’impression!”, and I didn’t understand but ok.. the ticket was there.
(plus demain…)
Then I caught the RERC to Austerlitz, when I arrived the Gare d’Austerlitz, I search for the ticket system, but I didn’t  know why I had to pass throw a machine of passengers, and actually I couldn’t because I needed a kind of ticket that allowed me to pass. So, I went to a train officer and ask: Je voulais aller, s’il vous plait!, and the guy told me: Vous êtes du Canada?, and I said: No, no, je suis portugais!, and the guy said: Ok, ok, tu peux aller!
I don’t know if the man was afraid of the Portuguese people, or if he liked very much the Portuguese people!?
Then continuing the journey, I went in direction to Orleans, and one hour later I had arrived. I thought for a few minutes: ” This is the beggining!”, and it was actually.
(plus demain)
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There’s a new power in America: Atheism

Not to say that a trend like this has never caught my mind, the US are fascinating and terrorizing at the same time. I just hope that with some more sense (atheism) they can help to make the world a whole lot better.

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Why Christianity Fails: Christopher Hitchens

Just some interesting videos I’ve found on youtube. Think about them…