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Nanoscale science gets a new periodic table, Nanopants skew public perception - news from the 2009 NSF NSE Meeting

Carol Lynn Alpert

A new systematic framework for unifying and defining nanoscience was put forth at the 2009 NSF NSE grantees meeting last week in Arlington, Virginia.

Donald Tomalia, director of the National Dendrimer and Nanotechnology Center at Central Michigan University, presented the scheme, describing it as comparable to the "first principles initiated by Lavoisier, Dalton, Mendeleev, and others that led to a periodic system and central paradigm for traditional elemental atom and small molecule chemistry." The framework posits twelve fundamental nano-element categories, divided evenly into two groups: metals (hard nanoparticles) and non-metals (soft nanoparticles). The hard nanoparticle categories include gold and other metal nanoparticles, metal oxide nanocrystals, silica nanoparticles, fullerines (buckyballs), and nanotubes. The soft nanoparticle categories include dendrimers, polymeric micelles, proteins, viral capsids, and RNA/DNA. Single units of all of the elements contain between 103 and 109 atoms and are 1 – 100 nanometers in size. In order to be included as an element, each type of nanomaterial had to exhibit (1) well-defined monodispersity (meaning more than 90% in solution disperse as a function of size and/or mass), (2) well-defined nanostructures, assemblies, or particles that mimic or behave like atoms, (3) well-defined stoichiometries (quantitative constants) and mass combining ratios, and (4) nano-periodic property patterns. From this basic 12 element nano element roadmap, Tomalia builds tables of nanoparticle compounds, that can be characterized by the proportion of each of these twelve basic elements they contain. For instance, a compound consisting of a single gold nanoparticle (hard element #1), bonded with six DNA strands (soft element #6) is what Chad Mirkin describes assembling and testing in a 2008 paper in Nature. (See my last RISE Rap entry for a report on Chad Mirkin’s work with this particular species). Tomalia demonstrated how this type of categorization can also yield predictable nano-periodic property patterns in size, shape, surface chemistry, and self-assembly patterns, analogous to the way the classic periodic table yields predictions about characteristics of groups of atomic elements, including valences and reactivity. Tomalia’s paper is published in the Journal of Nanoparticle Research 11 (1251-1310) 2009, and his powerpoint delineating the new model is available on the NSE 2009 meeting website at a link from the program agenda posted at http://www.nseresearch.org/2009/program.htm [Some of the other talks mentioned in this blog post are also linked from this listing, and posters are accessible from the list at the upper left of the web page]. In other news from the meeting, NSF Deputy Director Cora Marrett outlined the current 2010 National Nanotechnology Initiative budget request for $423 million. She described a new emphasis on environmental, health and safety (EHS) that would involve coordination with the U.S. Department of Agriculture, the EPA, and the European Union’s EHS program for nano. Tom Kalil, the Obama administration’s Deputy Director of Policy for the Office of Science and Technology Policy (OSTP), assured attendees that the NNI continues to be a priority for the Obama Administration and that clean energy was a particular focus. Kalil also emphasized the urgency of improving STEM education and speculated that NSE could be a way to get youth excited about science. He advised the NSE research and education community to do a better job of communicating what there is to show for the $12 billion federal investment thus far – beyond stain-resistant pants – and cited technologies like the Mirkin spin-off company Verigen, which offers a vastly improved disease detection system, A123, an MIT spin-off that is taking lithium ion batteries to a new level, and NanoSolar, which announced $4 billion in new orders this last September. In casual conversation, Mike Roco wondered whether the Wilson Center’s nano consumer product list –which lists perhaps 1% of nanotechnology applications - many of which are out-of-date - has actually been too influential in shaping public awareness of how nanotechnology can impact society - with its focus on the more trivial and prone-to-hype consumer market. Roco pondered with evident skepticism how a $300 tennis racket could contain enough carbon nanotubes to significantly affect performance, when a single gram of carbon nanotubes can cost several hundred dollars. (This reminded me of the scene in the first Dragonfly Nano TV episode, in which Harvard graduate student Dave Issadore tries in vain to find clear evidence of any carbon nanotubes in a sample of a supposedly nanotube-enhanced hockey stick.) A selection of industry representatives were in attendance, and several of them pointed out how important it is to industry that the NNI accelerates the pace of EHS (environmental health and safety) studies leading to a clarification of an appropriate regulatory scheme. Companies do not want to invest heavily in bringing nanotechnologies to the market only to find out that the materials they are dealing with require restrictions on use, distribution, and disposal. Others commented on the general consensus, internationally, that self-monitoring and self-regulatory schemes do not work. There was considerable discussion of the "valley of death" phenomenon: the gap in funding between basic research and the point at which potential venture capital providers can justify investment with a relatively rapid ramp to marketability. James Rudd provided an interesting set of slides documenting a slew of small company ventures for which NSF had provided financial support through its SBIR and STTR programs. Jeff Welser, of the Nanoelectronics Research Initiative, laid out the NRI’s efforts to "demonstrate novel computing devices capable of replacing" the CMOS FET (Complementary Metal-Oxide Semi-Conductor Field-Effect Transistor)– the current paradigmatic logic switch of computing, by the year 2020, when Moore’s Law is expected to turn to ash through the collective heat generated by the billions of already nanoscale-sized electric switches powered up inside the tiny landscape of a single chip. To replace today’s on/off switch of electrons running through wires, candidates for the logic switch of the future include such "alternate state variables," as electron, nuclear, or photonic spin, phase transitions, quantum states, magnetic flux quanta, mechanical deformation, dipole orientation, and single molecular state changes. Graphene is emerging as an exciting new candidate material. NRI is co-funding 18 research projects at 15 NSF NSEC and MRSEC centers. [At MOS, Karine Thate and I have been working with Jeff Welser to develop a new presentation about nanotechnology and the future of computing – and it’s not an easy task, with all these new far-fetched possibilities!] U.S. forest and paper industry representatives presented the wonders of cellulose nano-crystals (CNC), which could transform the world of paper, if only they had some assurances about EHS and more funding for basic research. A representative from the USDA described efforts to create nanoscale sensors that could monitor food spoilage, label food products, improve the deliverability of micro-nutrients and reduce pathogenic binding to food materials. Yet risk perception researcher David Berube, from North Carolina State, said in his remarks that you could pretty much sum up all the European and U.S. public opinion data by saying it’s all about what’s in our FOOD, FOOD, FOOD. Berube noted that the American public still remains fundamentally optimistic about the benefit/risk ratio, without demonstrating much awareness or depth of understanding about nanotechnology. Interestingly, he called into question much of the survey methodology being used in collecting such opinion data; in particular, the practice of "priming" the question with a description or definition of nanotechnology. Speaking of real risks, Andre Nel, director of the University of California Center for Environmental Implications of NanoTechnology, in a talk entitled "Nanotoxicity as a Predictive Science," outlined an impressive logic model for organizing and prioritizing the Center’s extensive research program for evaluating the risks of a wide variety of nanomaterials under various environmental conditions. Nel was joined on the podium by an EU counterpart, Kenneth Dawson, director of the Centre for Bio-Nano Interactions at University College, Dublin, who, with long pauses and soft-spoken brogue, hammered down the necessity of exploring not just what an individual nanoparticle might bring into a human cell, but also what it drags along with it, by collecting "a corona" of varying species of native molecules as it passes through various tissues on its way into each cell. I came away from these talks hoping that researchers like Nel and Dawson, are in communication with Donald Tomalia, the Michigan scientist working on a periodic table of nano elements, so that the assessment of the impacts of various nanoparticles in vivo and in the environment might inform and be informed by the classification scheme being proposed. In a panel on some of the likely legacies of NNI-sponsored research, several research directors commented on the uncommon quality of graduate students being trained along the way – students with a real facility for teamwork across interdisciplinary boundaries. These observations provided a nice segue into my presentation on the third day, about the NISE Net’s interest in collaborating with research centers to provide training to early-career researchers in science communication and engagement skills. In outlining the Donahue Institute’s evaluation of our MOS Science Communication Workshops for REU (Research Experience for Undergraduate Students), the talk was intended to show how a program that met faculty goals for training students to deliver better science presentations for their peers in interdisciplinary areas of nano research could also help them become more interested and knowledgeable about exploring the broader impacts of their own and others’ research, more comfortable communicating their research to non-science audiences, and more confident about continuing their participation in research. We also tacked up a poster on this topic, co-authored by faculty at the Harvard NSEC and the Center for High-rate Nanomanufacturing. On the same panel, Larry Bell provided a comprehensive overview of the strategic aims of the NISE Network and its organizational structure and initiatives. Dave Ucko, NSF Program Officer for the NISE Net for its first four years, gave a highly complementary report on Network progress, and Richard Hudson provided an entertaining overview of Dragonfly TV Nano and its successful summative evaluation by Barbara Flagg. Flagg’s summative evaluation of the MOS-produced, Harvard and CHN-sponsored, nanotechnology research TV news segments on New England Cable News were also presented in a poster at the meeting – showing that science and technology news, if well-produced, can be much more engaging to viewers than national and local news, sports and weather - and that couch potatoes can indeed learn a lot from 3-5 minute doses of TV nano news. Speaking of TV, each evening of the meeting, attendees were invited to join Mike Roco to watch consecutive hours of a new short TV series on nanotechnology produced by a French company in English, apparently for broad dissemination. The film covered the discovery of C60 and carbon nanotubes, the development of the scanning probe microscope, and new applications in materials, IT, sports and medicine. The segments I saw featured the work of Rick Smalley, James Tour, Jim Heath, Rutledge Ellis-Behnke, Charles Lieber, and an interview with Roco himself. The programs utilized an on-camera host, French, and included many creative graphic elements and unusual settings for talking head interviews; though overall, the hour-long segments were probably too drawn out and too detailed for prime-time U.S. audiences. That just about wraps up this rap. Comments are welcome.