Chemical Engineering

Pastilles for cleaning

Company develops devices that eliminate bacteria and fungi inside air conditioning equipment

Colleagues in the doctoral program in the area of inorganic chemistry at the Chemistry Institute of the University of São Paulo (IQ-USP) at the beginning of the 90s, Carlos Alberto Alves de Carvalho and Rubén Dario Sinisterra Millán already nourished expectations of, one day, transforming their scientific knowledge into technological products that would benefit society. Putting this project into practice happened in 2000, when they started a company to produce pastilles impregnated with bactericides and fungicides, for the purpose of cleaning air conditioning equipment.

Much of the entrepreneurial idea was strengthened by Sinisterra in the United States, which he returned from at the end of the 1990 after postdoctoral studies at the Massachusetts Institute of Technology (MIT), an institution that inspired him even more in the prospect of allying research and development with business objectives. At the moment, he is a professor at the Chemistry Department of the Federal University of Minas Gerais (UFMG). His friend Carvalho, who lives in São Paulo, travels every week to work at the Chemistry Department of the Federal University of Ouro Preto (Ufop). The two of them, plus Professor Nelcy Della Santina Mohallem, also from Sinisterra’s department at UFMG, are the three founding partners of Scientia Tecnologia Química (STQ). The company is installed at the Incubator Center for Technological Companies (Cietec), housed in the building of the Institute of Nuclear Energy and Research (Ipen), located in University City, in São Paulo.

“We carried out a careful assessment of our knowledge and about the potential for potential products on the market, and we decided to concentrate on developing an effective solution, with a long-lasting effect, for fighting bacteria and funguses in central air conditioning systems”, says Carvalho. This is a serious and very common problem. Recycling the air that circulates in closed spaces, air conditioning apparatuses in commercial buildings, airplanes and trains, for example, condense a portion of the water vapor that forms during the cooling process, creating an accumulation of liquid in the trays inside them. If this is not given a proper treatment, the stagnant water inevitably transforms itself into an environment that is highly propitious for the formation of colonies of bacteria and funguses of the most varied kinds. And the air that passes through the equipment takes the microorganisms inside the buildings.

Sick buildings
That is why air conditioning systems end up contributing towards the configuration of the so-called sick building syndrome. The contamination of the indoor air can cause headaches, irritation in the eyes and throat, rhinitis, bronchitis, crises of asthma and pneumonia in people who remain a long time in contaminated places. “Besides the impact on human health and well-being, the air that contains biological agents affects companies’s productivity and is responsible for many absences from work”, Carvalho explains.

According to the entrepreneur, a suspicion of the syndrome should be taken into consideration whenever 20% of the people that frequent a building show respiratory problems and allergies in short intervals of time, or when the symptoms are not manifested in other environments. “The products commercially available today for cleaning air conditioning apparatuses have two kinds of restriction: they kill bacteria and funguses, but they need daily maintenance, or they have a prolonged action, but merely inhibit the growth of micro-organisms and do not act on those that have already accumulated in the equipment”, he explains. “Furthermore, there are products on the market for cleaning the ducts that remove dust and particulate matter, and these are necessary for a complete maintenance of air conditioning equipment, in conjunction of STQ’s product.”

STQ’s technological option from the beginning was to develop a pastille of a ceramic matrix containing a bactericide and a fungicide, extensively tested, that are not aggressive to the natural environment or to people. These products are prepared to be released progressively. For this to happen, the active principles are encapsulated in a substance called cyclodextrin, an oligosaccharide (from the group of sugars) that makes it possible to include or to host molecules inside its cavities.

All over the world, cyclodextrins are being used more and more by various industries, like, for example, the pharmaceutical, food and textile industries. “This product that we use makes the active ingredients more soluble in water, leaving the ceramic matrix absolutely intact”, notes researcher Mariângela de Burgos Martins de Azevedo. Before joining the team at STQ in 2002, she had built up experience in the area of compounds with cyclodextrins for encapsulating plant hormones, for the purpose of spraying with this product to increase the mass and the seeds of various kinds of plants. She did postdoctoral studies at the Chemical Biology Laboratory of the Chemistry Institute at the State University of Campinas (Unicamp), and afterwards acted as a researcher at the Campinas Agronomic Institute (IAC), with a project under FAPESP’s Young Researcher Program (see Pesquisa FAPESP nº 80).

Initial capital
Finding a public health problem and mastering a technology with potential for solving it were not sufficient, though, for Carvalho’s and Sinisterra’s venture. “We lacked the initial capital to corroborate the technical viability of the project”, Carvalho recalls. “It was the support from FAPESP that made it possible to create the company, by means of the Small Business Innovation Research Program (PIPE), which guaranteed funds for buying the equipment for the laboratory and for remunerating the business consultancies, as well as making it possible for us to be installed in the Cietec”, he says. Also, there was the National Council for Scientific and Technological Development (CNPq), which in April 2002, by means of the Program for Fixing Doctors (Profix), approved a project coordinated by Mariângela, in conjunction with the businessmen from STQ, for developing technology for the bactericidal devices used in the air conditioning equipment.

At the end of last year, says Mariângela, the technical viability of the pastille was confirmed. “Now, in the second stage of the project, we are working on simplification and on economic feasibility”, she says. The idea is to test new support matrixes for the bactericide, the fungicide and the cyclodextrin that show a good mechanical resistance, without requiring much heating up in the production process. The need for using industrial ovens with a temperature of up to 500 degrees centigrade makes the manufacture of the pastilles more expensive, by virtue of the enormous demand for energy to produce the heat.

Gradual release
“We have already achieved promising results with a material that has a relatively low cost and which is widely available in the country”, Carvalho explains. The name of this material, as of the fungicides and bactericides encapsulated in the pastille, and the kind of cyclodextrin that ensures the gradual release of the active ingredients are trade secrets and cannot be revealed. Mariângela does say, though, that in the first tests the new candidate matrix ensured the action of the active ingredients for over 15 days. And, in the Brazilian market at least, it will be enough to double the duration of these effects. “To start with, we worked with the prospects of an effect prolonged for three months, which was then the minimum interval for the maintenance of air conditioning systems, in accordance with a standard of the Brazilian Sanitary Surveillance Agency (Anvisa)”, says Carvalho. Today, the same body’s Administrative Order number 9, of April 2003, requires the apparatuses to be checked every month. Obviously, the need for cleaning the equipment and purifying the water accumulated in them more frequently increases the costs of their maintenance.

In the tests to be carried out from now onwards, there is also the objective of assessing the performance of the pastille outside the laboratory, and STQ is now in partnership with a few air conditioning apparatus maintenance companies. Recently, one of them suggested the development of another product, aimed at the maintenance of air conditioning systems in cars. The suggestion is being analyzed by the group of researcher-businesspersons. There is no lack of a market for the product that motivated STQ’s foundation and which should be ready for its commercial launch at the end of 2004. According to figures from the Brazilian Association of Refrigeration, Air Conditioning, Ventilation and Heating (Abrava), about 400 companies, most of them small or medium in size, operate in this sector, which has a total turnover of around R$ 1.1 billion a year. And the market for central air conditioning systems has been expanding strongly for eight years now its rate of growth is in the region of 20% a year.

Whether STQ is going to produce the pastilles is a question that is still open. “We may perhaps opt for outsourcing the production process, or even for transferring the technology to a large company”, Carvalho comments. And a new project that is at the stage of being detailed may perhaps strengthen the prospects for the provision of high tech services, with earnings based on projects and royalties. At the end of last year, STQ, which right at the start of its operations had only three founding partners, attracted into the partnership – alongside Carvalho, Sinisterra and Nelcy Mohallem, Professor Robson Santos, from the Physiology and Biophysics Department of the Biological Sciences Institute of the Federal University of Minas Gerais (UFMG). He is going to work on projects for pharmaceutical formulations, systems for the controlled release of drugs and pre-clinical tests for companies from the sector. “Three of them have already manifested interest in our knowledge, with the aim of encapsulating theirproducts in cyclodextrins and biodegradable polymers”, Carvalho reveals.

The Project
Development of a Chemical Device for the Controlled Release of Bioactive Principles for the Microbiological Treatment of the Indoor Air in Climatized Environments (nº 00/12776-3); Modality Small Business Innovation Research Program (PIPE); Coordinator Carlos Alberto Alves de Carvalho (STQ); Investment R$ 312,271.72 and US$ 4,000.0