Nanoshell-tagged cancer cells (top) are much easier to detect than unlabeled cells (bottom). Nanotechnology 19 (2008) 315102
Recent work from the Center for Biological and Environmental Nanotechnology has demonstrated that tiny particles called nanoshells can be used to improve the detection of breast cancer cells in a Petri dish. Nanoshells are tiny particles made from silica wrapped in an ultrathin coating of gold that can be targeted to attach themselves to a common type of breast cancer. The nanoshells’ ability to scatter light provides a beacon for researchers to detect the cancerous cells to which they have become attached. This technique is being optimized to allow clinicians to improve patient outcomes by detecting whether cancerous cells at the boundaries of the tumors have been removed during surgical resection. These results were published in the journal Nanotechnology in 2008.
Quantum dots have the potential to bring many good things into the world: efficient solar power, targeted gene and drug delivery, solid-state lighting and advances in biomedical imaging among them. But they may pose hazards as well. A team of Rice researchers has been working to discover the health risks of quantum dots, molecule-sized semiconducting nanocrystals that are generally composed of heavy metals surrounded by an organic shell. The researchers found that the organic coating could be easily degraded (i.e., weathered) at non-neutral pH, leading to the release of toxic metals, which caused bacterial and fungal mortality. At near-neutral pH bacteria exposed to quantum dots containing cadmium and selenium showed decreased rates of growth but did not die. On the positive side, the study also found certain proteins and such natural organic matter as humic acids may mitigate the effects of decomposing quantum dots by coating them or by complexing the metal ions released, making them less toxic. These results were published in Environmental Science and Technology in 2008.
Graduate Student Jesse Farrell in the Guanajuato plant.
CBEN scientists have signed an agreement with the University of Guanajuato and the Municipal Water and Sewerage Authority of Guanajuato (Simapag) to pilot test the use of nanotechnology to clean contaminated water in Guanajuato, Mexico. The agreement is the first known test of nanoparticles for water treatment in a municipal water treatment plant. The groundwater that Guanajuato uses as a partial source for drinking water contains arsenic, and this test bed will explore the possibility of using a nanomagnetite-packed column for the removal of arsenic either during or after sand filtration. Nanomagnetite is also known as “nano-rust” due to its small particle size and iron oxide chemical composition. Laboratory tests have demonstrated that nano-rust is very effective at removing arsenic from water.
Ultrashort nanotube modified to become free-radical scavenger.
Researchers in the NSF Center for Biological and Environmental Nanotechnology have modified tiny particles called single-walled carbon nanotubes (SWCNT) to become free radical super-scavengers. Free radicals have been implicated in many diseases such as Alzheimer’s, stroke and acute radiation sickness. Antioxidants essentially neutralize these compounds by disrupting the chemical reactions they can undergo, providing a potential new form of antioxidant chemotherapy. The researchers modified the SWCNT to make them soluble in water and explored their antioxidant properties through a technique known as the oxygen radical absorbance capacity assay. The modified SWCNTs were shown to be forty times more powerful in their antioxidant properties than the radioprotective dendritic fullerene, DF-1, a competing nanomaterial-based agent. The modified SWCNTs had little harmful effect when tested on cells in a Petri dish. These results were published in the Journal of the American Chemical Society in 2009.
Dr. Nichol at CBEN and Dr. Hutchinson at ATLAS teaching CHEM 570 Nanotechnology for Teachers, Spring 2009.
This year CBEN’s seminal course CHEM 570 Nanotechnology for Teachers is being taught simultaneously in two states, Texas and Colorado, using videoconferencing and online technology. During his sabbatical at the Alliance for Technology, Learning and Society (ATLAS) Institute at the University of Colorado in Boulder, Dr. John Hutchinson CBEN’s Director of Education, is exploiting distance learning technology to expand the reach and impact of CBEN’s professional development for teachers program. The result is a unique course that reaches 35 teachers from 13 Texas school districts at Rice campus led by Nichol, CBEN’s Associate Director for Education, and 12 teachers at the ATLAS Institute with Hutchinson, while six more join in from home via the Web watching streaming video feed. In addition, teachers in both classrooms are able to answer questions using wireless audience response systems (“clickers”) while the teachers at home participate via a web-based remote response system. All of the CHEM 570 classes have been made freely available on Rice’s webcast archive http://webcast.rice.edu/webcast as streaming video or podcasts.
Ninth-grade students test the strength of biomaterials in a Rice Bioengineering laboratory with Dr. Maria Oden.
A new one week summer academy launched at CBEN in 2008 was designed to engage at-risk 9th grade students in science and engineering and how to make college a reality. CBEN’s partnership with Project GRAD (Graduation Really Achieves Dreams), a national nonprofit organization that works in underresourced schools, significantly increases our ability to excite diverse groups of students about science. In this summer program, CBEN hosted 50 students (30% African American, 1% Caucasian, 68% Hispanic) on campus for four hours/day and, with the generous sponsorship from JP Morgan Chase, these students were able to sample a variety of science and engineering activities and learn from Rice University Faculty. For example, students visited a Rice University bioengineering lab where they used electro-cardiograms to evaluate their heart rhythms before and after exercising. They also investigated biomaterials by measuring the tensile strength of chicken bones under different conditions. They built circuits, took apart computers and learned how computer science can be used to analyze car racing from Dr. Richard Tapia. They toured chemistry laboratories, electrical engineering labs and investigated lasers with Dr. Dan Mittleman. Students also went on a field trip to Galveston to the Off Shore Oil Museum where they explored careers in the petrochemical industry. To provide an outside perspective, guest speakers visited campus to talk to these students about how they have used science and engineering in their careers outside of academia. Curricular materials were also developed to guide students through the different choices that they can make about careers. After the summer institute ended, the program continued with Project GRAD bringing students to several other institutions during the school year. As a final project, the 9th grade students presented a summary of their experience to middle school students. Surveys indicate that the interest in science and engineering careers increased as a result of the program.
As nanotechnology has moved out of the laboratory and into commercial products, many have begun to question the impact of nanoscale materials on health and the environment. Learning more about such impacts, however, presents a daunting task, given the number of potential products, the pace of innovation, and the need to share information and leverage costs toward a more efficient, timely international research effort. A major challenge has been to produce a global research strategy for predicting the interactions between engineered nanoparticles and biological systems so that biocompatible nanomaterials can be developed and applied safely. In 2007, more than 70 experts from 13 countries – in academia, industry, government and non-governmental agencies – accepted that challenge. In an unprecedented international collaboration, the International Council on Nanotechnology (ICON) convened two workshops aimed at defining a set of research needs for assessing potential nanotechnology impacts. A report published in May 2008 identified and prioritized 26 critical research areas into 2-, 5- and 10-year needs. The report, Towards Predicting Nano-biointeractions: An international assessment of nanotechnology environment, health and safety needs, has been downloaded over 1000 times and is available at http://tinyurl.com/iconrna.
Researchers can now do their own analysis of research on the risks of nanomaterials with a new tool unveiled at the website of the International Council on Nanotechnology (ICON). The ICON EHS Database Analysis Tool offers a way for researchers at universities, non-governmental organizations, government and industry worldwide to analyze ICON’s database of citations to peer-reviewed publications addressing nanomaterials’ environmental, health and safety impacts. The tool enables research comparisons, with every database entry assigned nine indices and each index including a trend across time. With the newly enabled features, a researcher can compare categories within a specific time range, track the progression of publications in a given category by month or year, generate and export custom reports and click on a report result to generate a list of publications meeting user-defined criteria. The database analysis tool was featured in a recent C&EN article and can be found at http://icon.rice.edu/report.cfm.
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