Glass Surface and Blood Coagulation

Abstract

PLATELET-FREE, citrated plasma, collected and handled in silicone-treated apparatus, has a very long clotting time on recalcification. The exposure to glass surface greatly shortens the clotting time, and various hypotheses have been advanced to explain this phenomenon^1–4. The present study is an attempt to examine certain aspects of this reaction by the exposure of various normal and pathological plasma specimens and plasma fractions to a standard glass surface in the form of glass ‘ballotini’ spheres of 0.12 mm. average diameter. The activity may be assessed either by recalcifying the activated specimen directly or by adding a sample to a standard volume of silicone-collected plasma and recording the re-calcified clotting time of the mixture. The use of this silicone plasma as a diluent is essential for testing samples which are devoid of one or more clotting factors (cf. Table 1). (For reasons to be discussed elsewhere, in some experiments ‘silicone plasma’ containing 2,000–10,000 platelets/c.mm. was used as the diluent for the activated, platelet-free samples.)