Binding of histamine by glass surfaces

Abstract

Tritiated histamine (Hm) is significantly bound by glass surfaces. Many of the characteristics of the Hm binding suggest a specific process. Binding reaches equilibrium in 40 minutes and can be prevented by unlabeled Hm. Scatchard analysis reveals two Hm binding sites with dissociation constants of 0.051 μM and 14.4 μM. Histamine is 78.9% bound to the glass surface after 40 minutes when the concentration of Hm is 4ng/ml. Hm binding to glass can be prevented by potassium phosphate buffers, EDTA, and 0.1M HCl and reduced by albumin, formic acid, and ethanol. Binding does not occur with quartz and is minimal with polystyrene tubes.