The sampling and assay of airborne biologically-active materials are important in a number of industrial and health related applications. The principle aim of the current work programme is to select a range of biologically-active materials relevant to the food, pharmaceutical, medicine and biotechnology industries, and characterise their airborne behaviour and quantify their measurement.
The procedures developed in the previous VAM study have been used to test the effects of aerosolisation on Deoxyribonuclease I, which is a therapeutic enzyme used in the treatment of lung disease. The enzyme was aerosolised at known concentrations in a solution of sodium chloride at three relative humidities. Atomisers with two different mechanisms were used. Collection fluids from the glass cyclone sampler were assayed for enzyme activity, and the ratios of experimental to expected airborne concentration were calculated. The results show that the activity of the enzyme is not significantly affected by aerosolisation at different humidities or from different atomisers.
The next stage of the work was to examine the effects of an additive on the activity of the aerosolised enzyme, and the impact on the recovery from three different bioaerosol samplers. The results showed that adding small percentages of polyethylene glycol to the spray suspensions made no significant difference to the enzyme activity under the harsh conditions experienced in the atomiser. Also, the additive had no detrimental effect on the stability of the enzyme when aerosolised and captured in three bioaerosol samplers.