A technique for separation of house dust mites (Acari: Pyroglyphidae) from culture media.

House dust mite materials containing D. farinae and their emanations were isolated from laboratory cultures by an ethanol suspension method, and an extract was prepared. The protein nitrogen content of this extract was 250 μg PN/ml. Allergenic potency of the extract was determined by scratch and intracutaneous skin testing. The extract showed good discrimination in patient sensitivity when tested with commercial house dust extracts.