ELECTROSTATIC CHARGE CHARACTERISTICS OF DER P1 ALLERGEN-CARRYING PARTICLES AND THE HOUSE-DUST MITE DERMATOPHAGOIDES-PTERONYSSINUS

Control of the house dust mite allergen has received considerable atte ntion owing to its importance in some allergic diseases. One aspect of dust mites and their allergen-carrying faecal particles that has not been reported on, which may have allergen control applications, is the electrostatic charge they carry in the natural environment. To promot e tribe-electric charging, household dust containing dust mite allerge n and live house dust mites are separately agitated while in contact w ith either polypropylene, nylon or earthed metal. The charged dust and mites are subsequently subjected to electrostatic separation and coll ection. Results for concentrations of the house dust mite allergen, De r pi, indicate that, when subjected to nylon, Der pi carrier particles appear to be predominantly positively charged. Similarly, when subjec ted to polypropylene, Der pi carrier particles also appear to be posit ively charged. Reduction of excess free charge by agitation against ea rthed metal does not appear to affect the observed charging characteri stics, indicating that the positive charge may be hound or inherent in the Der pi carrier particles. In contrast, house dust mites exposed t o nylon appear to be generally charging negative, whereas mites expose d to polypropylene appear to be charging positive. The observed electr ostatic characteristics of the mites and Der pi carrying particles wil l be useful in the future development of electrostatic allergen contro l methods.