There are no clinical methods for the quantitative estimation of sugar in the blood. The chemical methods that are in vogue are also not specific for glucose. Certain of these methods determine the reducing substances in the blood. By the polariscopic method we obtain the total quantity of optically active substances in the circulation. Those methods in which the glucose in the blood is extracted by certain solvents have no clinical value, because the amount of blood necessary for each test is too great.
The test here recommended determines the quantity of "reducing" substance in the blood. It is based on Bang's process. Control tests were made with various known solutions of glucose and accurate quantitative results were obtained. The process is very simple and should require not more than from ten to fifteen minutes for the whole analysis. Two solutions are prepared:
Copper Solution: Five hundred gm. of potassium