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University has at least 20
working groups working in the particle area

Nanoscience. Unicamp brings together its 20 groups


MARIA TERESA COSTA

A nanotechnology and nanoscience are still beginning in Brazil, but Unicamp already has a significant number of researchers working on exploring the properties of particles on an atomic scale and working on building complex structures, atom by atom. In an area where everything is measured on a scale a million times smaller than a millimeter, Unicamp already has at least 20 groups involved in this field where there are still many phenomena to be explained, studied or even discovered. This is a considerable number for a single university, notes professor Oswaldo Luiz Alves, from the Chemistry Institute. The production of some of these groups has already produced important results, as is the case with a patent for a nanocomposite obtained from a mixture of clays and polymers that could be used in packaging. "This material will solve one of the problems related to oxygen permeability. Any substance that cannot be packaged in plastic, such as beer, for example, can be stored in a container based on this nanocomposite", he states. This project was developed within the scope of the Millennium Institute of Complex Materials, of the Ministry of Science and Technology, coordinated by professor Fernando Galembeck, of the Institute of Chemistry.

The researcher notes that the important thing is to introduce functionality to things on such small scales. Functionality is provided by adding intelligence (or molecular recognition) to nanostructures. This model opens up the possibility of using them as vehicles to administer medicines, for example. This functionality has been sought by the group coordinated by professor Marcello Mantovani Martiniano de Azevedo, from the Biological Chemistry Laboratory, at the Chemistry Institute, which is formulating biodegradable polymer micro- and nanoparticles that carry compounds with important pharmacological activity. Among these compounds would be violacein, which has antitumor, antituberculosis and antiviral activities, trans-dehydrocrotonin (antiulcerogenic), in addition to other compounds of recognized therapeutic importance, such as isoniazid and streptomycin.

There are many theoretical works that are important in the area of ​​nanoscience, recalls physicist Fernando Cerdeira, who is part of the Optical Properties Group of the Department of Condensed Matter Physics, of the Institute of Physics. This group investigates electronic, transport and optical properties in semiconductor heterostructures and nanostructures and semiconductor optical properties.

One of the groups that works in basic science is coordinated by professor Marcelo Knobel, from the Materials and Low Temperatures Laboratory of the Institute of Physics. The group has been producing magnetic nanocrystalline materials with different methods and studying their formation, evolution and final physical properties. “In particular, we try to understand how to modify or optimize certain properties that may be useful in applications, or even understand phenomena that arise and no one yet knows why,” he says. These are studies, notes Knobel, that could be important when computer systems have increasingly smaller bits of information.

In the area of ​​Biology, however, the experiments are still very early, according to professor Maria Alice Cruz-Hofling, who is part of the group led by Vítor Baranauskas, from the Faculty of Electrical and Computer Engineering. This group has been obtaining processes for generating diamond or carbon micro- and nanotubes, with different porosities and terminations for applications, for example, in molecular tubular sieves, implants and prostheses, and strongly luminescent field emission devices. This group used atomic force nanoscopy to analyze biosystems, formed by cells and biomolecules or through in-vivo experiments.

Jobs win international projection

The work in nanotechnology and nanoscience that has been developed in the most different laboratories at the university has already gained international repercussion in important publications. This is the case of studies on the use of gold wires in nanoelectronic circuits, developed by three Brazilian physicists, including researcher Edison Zacarias da Silva, from Unicamp. The research, published in the journal Science, received the reference for best world literature in materials science from editor M. Levine. Physicists used molecular dynamics simulations and first-principles calculations to study the gold wire's structures, showing the formation, evolution and breakage of a nanowire. The study details how gold atoms behave when stretched until they form a single thread, which only breaks after obtaining a chain of up to five atoms in a row. A large part of the studies that have been taking place at the university concern the search for understanding and control of matter at the nanometer scale or, more broadly, from the atom scale to around 100 nanometers. But there is also applied science being produced. One of the areas that should be of broadest interest within Unicamp is microsystems (MEMS), in the opinion of the coordinator of the Center for Semiconductor Components and professor at the Faculty of Electrical and Computer Engineering, Jacobus Swart. The production of machines as small as a strand of hair, but with electrical and mechanical components, is increasingly necessary to automate and improve processes with applications in various areas. This line includes biosensors and various types of sensors for chemical, biological measurements, among others. Swart is part of a group that has been dedicated to optimizing processes and characterizing nanotubes, planning to use them in sensors and other devices and for nanoinstrumentation. The microfabrication of three-dimensional scaffolds for tissue engineering is another investigation that is underway within Unicamp, involving researchers from the Department of Materials at the Faculty of Mechanical Engineering and the Center for Semiconductor Components. The group, led by Cláudio Cutrim Carvalho, from FEM, has been using soft lithography to generate, on the surface of biomaterials, patterns and morphological arrangements capable of influencing important physical and biological events that determine, for example, cell adhesion to a substrate, expression phenotypic and cell growth. There is a group, led by researcher Luiz Carlos Kretly, from the Department of Microwaves and Optics at the Faculty of Electrical and Computer Engineering, which is investigating the propagation of electromagnetic waves in carbon nanotubes. As carbon nanotubes are elements with great potential for applications, the group intends to use this device for nanoscale communication, ranging from connections between optical transistors to communication channels for nanorobotic devices in medical applications.

Workshop will add efforts

On June 5th and 6th, Unicamp will bring together researchers from the university and the Campinas region who work in the most diverse areas with a special interest in nanoscience and nanotechnology. More than generating contacts between researchers and exchanging information between groups that already operate on a billion-millimeter scale, Unicamp hopes for the emergence of multidisciplinary programs in nanoscience or nanotechnology.

Organized by the Dean of Research, the Workshop will have 19 oral presentations and 17 panels that will allow participants to present the facilities, capabilities and competencies of their research groups. The Workshop, says the advisor to the Dean of Research, Roberto de Alencar Lotufo, will be an opportunity to learn about the university's instrumental and equipment facilities, maximize their use and create new possibilities. "This is perhaps the university's first effort to know exactly its capabilities, facilities and instrumentation for a specific area," he notes.

The proposal, according to physicist Fernando Cerdeira, who is part of the Organizing Committee of the Workshop on Nanoscience and Nanotechnology, is to bring together people who are currently developing projects on their own initiative and thus stimulate the emergence of a project that could eventually have an impact. in this area. "We have researchers, people are working, but there is a certain lack of knowledge among the groups and researchers among themselves and the potential that could be developed if several of these people and groups decided to embark on a project together", he believes

Professor Jacobus Swart, from the Faculty of Electrical and Computer Engineering and who is also part of the Workshop Organizing Committee, exemplifies this. "We work with microfabrication and nanofabrication technology. We have some infrastructure and some knowledge in this area, but we lack greater contact with people who need these structures for other fabrications", he says.

There is already collaboration between the areas, but it can be more comprehensive and that is what the university is looking for at the moment, being able, based on the interest of the different groups, to lead to a multidisciplinary program in nanoscience and nanotechnology, assesses professor Oswaldo Luiz Alves , from the Institute of Chemistry. In addition to Lotufo, Cerdeira, Swart and Alves, the Workshop Organizing Committee includes professors Maria Alice Cruz-Höfling, from the Biology Institute, and professor Fernando Galembeck, from the Chemistry Institute.

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