Influence of Light Rays on Coagulation of Plasma and Fibrinogen

Abstract

It has been shown by many experiments that proteins are highly susceptible to the action of ultraviolet rays. 1 , 2 Mond 3 claims an increase in stability of globulin and fibrinogen solutions when irradiated with U. V., which may correspond to the behavior of a well defined colloid, congorubin. 1 Howell 4 was able to demonstrate delayed coagulation of fibrinogen solutions and when hematoporphyrin was added to such solution before irradiation no coagulation occurred.

The experiments recorded in this paper are concerned with: (1) comparison of various kinds of light on the coagulation-time; (2) comparison of the coagulation time of plasma on one hand and solutions of fibriuogen on the other.

Fresh beef blood from full grown animals was oxalated and the plasma separated by centrifugation. A portion of the plasma was used to prepare fibrinogen according to the method described by Hektoen and Welker. 5

The light sources used for the experiments were: (1) The high pressure mercury-quartz lamp, characterized by its very effective U. V. spectrum with only a few visible lines. (2) The carbon-arc lamp, used with carbons containing various metals to produce different kinds of continuous spectra.

(a) The C-carbon, producing besides visible rays a very large quantity of ultraviolet.

(b) The SS-carbon, giving much energy in the infra-red, visible and near ultraviolet regions but a very low output in short wave U.V.

(c) The E-carbon, emitting large quantities of visible and infrared light but practically no ultraviolet.

Small quartz tubes containing 1 cc of oxalated plasma or of fibrinogen solution were exposed to the influence of the rays for 10, 20 and 30 minutes. Use of a fan prevented temperature variations exceeding 3 °C.