Non-specific adsorption of corticotrophin-releasing factor (CRF) to powdered glass

CRF activity from various sources (rat hypothalamic median eminence and posterior pituitary, bovine hypophyseal stalk, and human peripheral blood) was adsorbed to finely ground glass (Quso, Corning, CRF activity was eluted from the glass with 30% acetone. Up to 85% of the total CRF activity originally present in the crude CRF preparation was adsorbed to Quso or Corning glass; up to 25% of the original total CRF activity was recovered from the glass with 30% acetone. We conclude that CRF is among the hormones adsorbed by glass.