Novel home cleaning method to reduce asthma

The patents (Methods and Compositions for Eliminating Allergens and Allergen-Producing Organisms) are the work of Michael Matthews, Jian Zhang and Allan Quick and uses carbon dioxide (CO₂) to "freeze clean" home fabrics. The process deactivates proteins found in pet dander and can remove smoke residue and other allergy-causing substances. The freezing process also kills dust mites embedded in carpets and mattresses, which feed off human skin particles and are a major cause of asthma.

The researchers are currently perfecting the application method, which utilizes CO2 vapor sprayed directly on fabric. The vapor cools on expansion to form tiny micro-pellets of dry ice that are quickly vacuumed up and the result is completely dry fabric free of allergy-causing agents. Early tests suggest a single cleaning treatment lasts approximately six months and does no harm to the fabric.

The work is funded with multiple external grants, including two from the National Institutes of Health.

About 7 million children, more than 9 percent of the entire child population in the U.S., suffer from asthma, according to the Centers for Disease Control. Asthma rates are even higher for minority and low-income children and asthma attacks also are responsible for 1.8 million emergency room visits each year.

Matthews, a professor of chemical engineering at USC's College of Engineering and Computing, said the method could eventually be ordered by physicians as an effective intervention for children with asthma.

"Our original concept, both in research and in our startup, was to commercialize carbon dioxide technology for medical sterilization," Matthews said. "However, we realized that there was a critical national need to address the removal of asthma triggers from the home. These triggers, which are actually proteins produced by pets and pests, can be removed with our technology."