Poster presenters needed for symposium on environmental, health impacts of nanotech

2009 INBT Poster Session (Photo: Jon Christofersen)

Poster titles are now being accepted for Johns Hopkins Institute for NanoBioTechnology’s fourth annual symposium, “Environmental and Health Impacts of Engineered Nanomaterials” set for Thursday, April 29, at the Bloomberg School of Public Health. Researchers from across the university, from government and industry, and from other universities are invited to submit posters by the deadline of April 22.

All students, faculty and staff affiliated with any Johns Hopkins campus or school may attend the symposium for free. Students from UMBC and Morgan State University may also attend at no cost.

This year’s symposium brings together faculty experts engaged in various aspects of nanotechnology risk assessment and management research. Jonathan Links, an INBT-affiliated professor in the Department of Environmental Health Sciences at the Bloomberg School, assembled the slate of speakers from across four divisions of the university.

Links said that this diversity reflects the multidisciplinary approach needed to effectively address questions of how nanomaterials move through and interact with the environment, and how they may impact biological organisms, including humans. Links added that despite some concerted efforts to assess risk, many questions remain unanswered about how engineered nanomaterials and nanoparticles impact human health and the environment.

“Without these data, we are flying blind. But when risk assessment is performed in tandem with research into beneficial applications, it helps researchers make better decisions about how nanotechnology is used in the future,” Links said.

Along with Links, professors from the Bloomberg School presenting talks at the symposium include Ellen Silbergeld, of Environmental Health Sciences, and Patrick Breysse, of Environmental Health Engineering and Environmental Health Sciences. William P. Ball, a professor in the Whiting School of Engineering’s Department of Geography and Environmental Engineering; Justin Hanes, a professor in the School of Medicine’s Department of Ophthalmology, with joint appointments in the Whiting School’s Department of Chemical and Biomolecular Engineering and the Bloomberg School’s Department of Environmental Health Sciences; and Howard Fairbrother, a professor in the Krieger School of Arts and Sciences’ Department of Chemistry, will talk about the transport of nanomaterials through environmental and biological systems, as well as the unusual properties of manufactured nanomaterials.

Tomas Guilarte, recently appointed chair of the Department of Environmental Health Sciences at Columbia University’s Mailman School of Public Health and a former professor at the Bloomberg School, will provide a presentation on neurotoxicity of nanoparticles. Ronald White, an associate scientist and deputy director of the Bloomberg School’s Risk Sciences and Public Policy Institute, will discuss policy implications based on risk assessment.

Symposium talks will be from 8:30 a.m. until noon in Sheldon Hall (W1214), and a poster session, with prizes for top presenters, will be held from 1:30 to 3 p.m. in Feinstone Hall (E2030).

To register for the symposium or to display a poster, click here.

For more information about INBT’s fourth annual symposium, click here.

Story by Mary Spiro

Nonlinear Optics on the Nanoscale: Towards Terabit Optical Processors

Ben Eggleton

The Department of Electrical and Computer Engineering presents The Jan M. Minkowski Memorial Lecture in Quantum Electronics, “Nonlinear Optics on the Nanoscale: Towards Terabit Optical Processors”, with speaker Dr. Benjamin J. Eggleton, ARC Federation Fellow, School of Physics, University of Sydney, Friday, March 26, 2010, 3:00 p.m., Mason Hall Auditorium, Homewood Campus. Reception to follow.

Abstract

Nonlinear optics describes the behavior of light in media in which the dielectric polarization P responds nonlinearly to the electric field E of the light. This nonlinearity is generally only observed with very high power pulsed lasers. For this nonlinearity to be useful – as an optical switch, for example – we need a material with a massive nonlin-ear response so that the nonlinear effects can be generated at low power levels. This talk will review our progress on developing photonic inte-grated circuits based on breakthroughs in highly nonlinear materials and nanophotonics. We have demonstrated all-optical ultrafast information processing and we have demonstrated a monolithic integrated photonic chip with terabit per-second bandwidth. Our approach takes advantage of different ultrafast nonlinear processes, such as four-wave-mixing and stimulated Raman scattering processes and also exploits dispersion engineering and slow-light effects. I will present our recent record-breaking results demonstrating information processing at terabit per second speeds and will discuss prospects for implementation in next generation high bandwidth information systems.

About the Minkowski Memorial Lecture

Jan Minkowski was born in Zurich, Switzerland and raised in Warsaw, Poland. He received his first degree in Electrical Engineering in 1938 from the Warsaw Polytechnic Institute. He served as an officer in the signal corps of the Polish Cavalry from September, 1939, until his liberation from six years as a prisoner of war in 1945. He then resumed his studies in the Department of Mathematics and Physics at E.T.H., Zurich. He wrote his Diplomarbeit dissertation under the direction of Prof. Wolfgang Pauli and continued to work under his supervision at the Institute of Theoretical Physics until 1950.

Prof. Minkowski emigrated to the United States and joined the Radiation Laboratory of the Johns Hopkins University in 1952. He entered the graduate program of the Department of Physics at Johns Hopkins and received his Ph.D. in physics in 1963. He then became a faculty member in the Department of Electrical Engineering at Johns Hopkins where he remained until his retirement in 1987. His research interests were in the areas of masers, lasers, solid state physics, microwaves, coherence properties of light, and quantum optics.

Link to the flyer here.

Probing the Soft Side with Nanoindentation Techniques

Michelle Oyen

Michelle L. Oyen of Cambridge University Engineering Department  will present the talk  “Probing the Soft Side with Nanoindentation Techniques” on Wednesday, March 24 at 3 p.m. in Maryland Hall 110. Dr. Oyen is a lecturer in Mechanics of Biological Materials in the Mechanics and Materials Division and the Engineering for the Life Sciences group at Cambridge University. This seminar is hosted by Professor Tim Weihs and the Johns Hopkins University Department of Materials Science and Engineering. The talk is free and open to all Johns Hopkins faculty, staff and students.

Abstract

The mechanical properties of many “soft” materials are of interest for biomedical applications, including both natural tissues and hydrogels for tissue engineering applications. In the last 15 years, nanoindentation techniques have gained prominence in the mechanical testing community for three reasons: first, the fine resolution in load and displacement transducers, second the fine spatial resolution for mapping local mechanical properties, and finally the relative ease of performing mechanical testing. In the current studies, we extend the scope of nanoindentation testing with commercial indenters to quantitative measurements on kPa materials. Different forms of the material constitutive response were considered with an emphasis on time-dependent viscoelastic or poroelastic deformation. Applications are the considered for hydrated tissues and hydrogels including articular cartilage, bone and mechanically graded hydrogels. Further investigations using adaptations of these nanoindentation techniques examine nano-scale adhesion and mechanical outcomes in stem cell differentiation. This study demonstrates the potential for high-throughput mechanical screening of soft materials and for mapping property gradients in inhomogeneous materials as these approaches can now be extended to materials in the kilopascal elastic modulus range.

Hopkins biomedical engineering doctoral student wins Weintraub Award

Deok-Ho Kim

Deok-Ho Kim, currently a postdoctoral fellow in the department of Biomedical Engineering, was among 13 graduate students from North America chosen to receive the 2010 Harold M. Weintraub Graduate Student Award, sponsored by the Basic Sciences Division of Fred Hutchinson Cancer Research Center in Seattle, Wash. Nominations were solicited internationally and winners were selected on the basis of the quality, originality and significance of their work.

The award, established in 2000, honors the late Harold M. Weintraub, Ph.D., a founding member of the FHC’s Basic Sciences Division, who in 1995 died from brain cancer at age 49. According to a press release from FHC, “Weintraub was an international leader in the field of molecular biology; among his many contributions, he identified genes responsible for instructing cells to differentiate, or develop, into specific tissues such as muscle and bone.”

Kim will receive a certificate, travel expenses and an honorarium from the Weintraub and Groudine Fund, established to foster intellectual exchange through the promotion of programs for graduate students, fellows and visiting scholars. Kim works in the laboratory of Andre Levchenko, associate professor of biomedical engineering at Johns Hopkins University’s Whiting School of Engineering and an affiliated faculty member of the Institute for NanoBioTechnology.

Read more about Kim’s research with Levchenko here.

APL scientist to explain self-assembled artificial cilia from cobalt nanoparticles

Jason Benkoski

Jason Benkoski

Can nanoparticles be used to engineer structures that could be as flexible and useful as the cilia that help bacteria move around?

Jason Benkoski, a senior scientist at Johns Hopkins Applied Physics Laboratory and an affiliated faculty member of Johns Hopkins Institute for NanoBioTechnology, will discuss his current research in this endeavor on March 1  at 1:30 p.m. in the Rome Room, Clark 110 at the Johns Hopkins University Homewood campus. Hosted by the Department of Biomedical Engineering, this talk also will be teleconferenced to the Talbot Library in Traylor 709 at the School of Medicine.

Abstract: Taking inspiration from eukaryotic cilia, we report a method for growing dense arrays of magnetically actuated microscopic filaments. Fabricated from the bottom-up assembly of polymer-coated cobalt nanoparticles, each segmented filament measures approximately 5–15 microns in length and 23.5 nanometers in diameter, which was commensurate with the width of a single nanoparticle. Boasting the flexibility of biological cilia, we envision applications for this technology that include micropumps, micro-flow sensors, microphones with hardware-based voice detection, surfaces with enhanced thermal transfer, switchable, tunable filters, and microscopic locomotion.

Additional Links:

Jason Benkoski’s INBT profile

Johns Hopkins Applied Physics Lab

Drazer wins NSF Career Award

German Drazer

German Drazer (Photo: Will Kirk)

German Drazer, assistant professor in the Department of Chemical and Biomolecular Engineering and affiliated faculty member of Johns Hopkins Institute for NanoBioTechnology was recently named a recipient of the National Science Foundation Faculty Early Career Development (CAREER) awards, given in recognition of a young scientist’s commitment to research and education. Drazer was given the award for “Deterministic and Stochastic Transport of Suspended Particles in Periodic Systems: Fundamentals and Applications in Separation Science.” The grant will support his investigations into the transport phenomena that arise in the motion of suspended particles in spatially periodic systems, and the translation of these phenomena into new principles for the manipulation of suspended particles in fluidic devices.

Read more about the work in the Drazer Lab here.

INBT researchers use LEGO to study what happens inside lab-on-a-chip devices

New Hopkins materials science faculty to explain ‘flash nanoprecipitation’

Margarita Herrera-Alonso

Margarita Herrera-Alonso

Margarita Herrera-Alonso, a new assistant professor in Johns Hopkins Department of Materials Science and Engineering, will present the talk, “Block Copolymer Nanoparticles by Flash Nanoprecipitation: Prodrug Strategies,” on Feb. 3, 2010, at 3 p.m. in Maryland Hall 110. This talk is part of the Materials Science seminar course (EN 510.804), but all Hopkins students, faculty and staff are invited to attend.

Abstract

Colloidal particles are proven effective carriers for therapeutic and imaging agents. Protection of solutes (therapeutic and/or imaging) by encapsulation in colloidal particles enhances their biodistribution and pharmacokinetics, prevents degradation during transport, and allows for triggered/controlled release. Choice of the carrier–dendrimer, micelle, liposome, nanoparticle– is largely determined by its loading efficiency, drug content, and delivery rate. Polymer-based carriers are particularly useful given their chemical, compositional and architectural versatility. We are interested in the formulation of drug-loaded polymer-based nanoparticles. The uniqueness of these nanoparticles relies on the method by which they are produced: Flash Nanoprecipitation. Successful encapsulation of solutes in polymer nanoparticles by Flash Nanoprecipitation depends on establishing rapid micromixing conditions and balancing the kinetics of block copolymer self-assembly and solute precipitation. While Flash Nanoprecipitation is an extremely versatile method for solute encapsulation, the resultant nanoparticles are not exempt from undergoing solvent-mediated interparticle mass transfer. This instability can be attenuated by the use of prodrugs. Specific examples of estradiol prodrugs and their encapsulation in a series of poly(ethylene glycol)-based copolymers will be discussed.

Whiting School of Engineering Department of Materials Science and Engineering

Princeton physicist to discuss physics of cancer cell resistance

Physics professor Robert Austin, right, and graduate ¬student Guillaume Lambert observe prostate cancer cells growing on chips of silicon and silicon-based plastic. (Princeton Office of Communications)

The fact that cancer cells frequently re-emerge after initial therapeutic attempts has dogged the efforts of oncologists to save patients’ lives for decades. According to Princeton physicist, Robert H. Austin, cancer cell resistance is primarily a biological reaction to stress and “one of the great unsolved, and deadly, problems in oncology.”

On Thursday, February 4, Austin will discuss, “The Physics of Cancer,” during a 3 p.m. joint colloquium hosted by Johns Hopkins University departments of Physics and Astronomy and Biophysics in the Schafler auditorium of the Bloomberg Center on the Homewood campus. The talk is free and open to the public.

Austin is principal investigator for Princeton’s Physical Science-Oncology Center and a trans-network partner with Johns Hopkins Engineering in Oncology Center, both of which are National Cancer Institute funded organizations.

Austin will address the general principles of physics, ecology, and biology and why recurrence of resistant cancer cells seems to be a universal phenomenon in cancer. He says that “evolution in small, stressed habitats is key to the rapid and inevitable re-emergence of resistance of cancer cells” (and) “that modern techniques of physical probes, genomics, proteomics and nanotechnology will allow us to analyze the evolutionary path of these emergent resistant cells.”

Related Links

Johns Hopkins Engineering in Oncology Center

Flyer for  Prof. Austin’s colloquium

Physical Sciences in Oncology Centers of the National Cancer Institute

Animator, scientist partner to illustrate cover of Advanced Materials

AM_3_U1resizeThe cover of the January 19, 2010 issue of the journal Advanced Materials features a photo illustration executed by Martin Rietveld, web director and animator at Johns Hopkins Institute for NanoBioTechnology. Rietveld’s work illustrates an article about chemomechanical actuators—grippers that open and close like a hand in response to chemical reactions. The paper is based on the research of lead author, doctoral student Jatinder Randhawa in the laboratory of David Gracias, associate professor of chemical and biomolecular engineering and faculty affiliate of the Institute for Nanobiotechnology. Randhawa conceptualized the illustration of his research for the journal cover.

Says Gracias, “Chemomechanical actuation is intellectually appealing since it is widely observed in nature, but chemomechanical actuation is relatively unexplored in human engineering where the dominant strategy to actuate structures is based on electromechanical actuation (i.e. with electrical signals). Here, microstructures open and close reversibly in response to chemical surface oxidation and reduction without the need for any wires or batteries.”

Related links:

Chemomechanical Actuators: Reversible Actuation of Microstructures by Surface-Chemical Modification of Thin-Film Bilayers. Jatinder S. Randhawa, Michael D. Keung, Pawan Tyagi, David H. Gracias.

Johns Hopkins Institute for NanoBioTechnology Animation Studio

David Gracias INBT Faculty Profile

Environmental, health impacts of engineered nanomaterials theme of INBT’s annual symposium

By 2015, the National Science Foundation reports that the nanotechnology industry could be worth as much as $1 trillion. Nanomaterials have many beneficial applications for industry, medicine and basic scientific research. However, because nanomaterials are just a few atoms in size, they also may pose potential risks for human health and the environment.

Cross-sectional autoradiograms of rodent brains showing (A) control physiological state; and (B) and (C) showing distribution of brain injury from an injected neurotoxicant. Red areas indicate the highest concentrations of a biomarker that identifies brain areas that are damaged by the neurotoxicant. (Guilarte Lab/JHU)

Cross-sectional autoradiograms of rodent brains showing (A) control physiological state; and (B) and (C) showing distribution of brain injury from an injected neurotoxicant. Red areas indicate the highest concentrations of a biomarker that identifies brain areas that are damaged by the neurotoxicant. (Guilarte Lab/JHU)

To increase awareness of Hopkins’ research in this emerging area of investigation, the theme for the fourth annual symposium hosted by Johns Hopkins Institute for NanoBioTechnology (INBT) will be environmental and health impacts of engineered nanomaterials. INBT’s symposium will be held Thursday, April 29, from 8 a.m. to 3 p.m. at the university’s Bloomberg School of Public Health in Baltimore, Md.

Morning talks in Sheldon Hall by eight Hopkins faculty experts will discuss neurotoxicity, exposure assessment, manufacture and characterization of nanomaterials, policy implications and many other topics. In the afternoon, a poster session will be held in Feinstone Hall featuring nanobiotechnology research from across the university’s divisions.

INBT is seeking corporate sponsorships for the symposium. Interested parties should contact Thomas Fekete, INBT’s director of corporate partnerships at tmfeke@jhu.edu or 410-516-8891.

Media inquiries should be directed to Mary Spiro, INBT’s science writer and media relations director, at mspiro@jhu.edu or 410-516-4802.

A call for posters announcement will be made at a later date.

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