At the heart of the expoCube system is the cube itself. Commercial Transwell® plates are seeded with cells and inserted in the expoCube. The expoCube is compatible with a wide variety of aerosols such as nebulized drugs, dry powder formulations, atmospheric pollutants, agro-chemicals, volatile organic compounds (VOCs), complex gaseous and particle mixes generated by tobacco and electronic cigarette, and a wide variety of other airborne substances.
Once activated, the precision-engineered expoCube precisely guides aerosols onto the target cells and tissues. An innovative sealing mechanism fully isolates the apical and basal sides of the well. Heaters maintain the cells at a set control temperature of 35C throughout the experimental cycle.
The expoCube features eight individual exposure sites, each linked to separate well inserts. During a typical experiment, four of the wells are exposed to an aerosol of interest, four other wells act as controls, and the last four wells are “non-exposure” control cultures.
Two main flow channels carry the air and the aerosol across the system. Each of the eight exposure sites is fed by precision micro-flows that draw from either of the main flow channels. The main flow and microflow channels are controlled by the expoCube Control Unit with a high degree of accuracy
The Transwell plate temperature is precisely controlled to ensure a natural environment to the cells and to improve the particle deposition efficiency. As aerosol particles travel through the expoCube, they are heated up 50C. A large fraction of the particles are guided to deposit uniformly on the target wells. Traditional in vitro exposure systems typically only deliver ~2% of the small particles onto the Transwell. The expoCube achieves a vastly superior (~40%) deposition rate by relying on a combination of unique geometry and thermophoresis effect. Thermophoresis is a physical process by which the small particles follow the temperature gradient over a short distance.
