Determination of Reduced Ascorbic Acid in Small Amounts of Blood

Observations on the Renal Threshold for Ascorbic Acid in Man

“…The close dependence of the values for ascorbic acid in the blood serum or plasma upon the nutritional state of the organism has also been well established (1,3,7,8). Low levels of serum ascorbic acid have been demonstrated in subjects suffering from vitamin C undernutrition with or without manifest scurvy and in the presence of infection (9).…”

A Study of Ascorbic Acid Metabolism of Adolescent Children

“…All of the food eaten by the children for a period of three weeks was weighed, and the amounts recorded Samples of all foods which were known or presumed to contain ascorbic acid were analyzed by the method of Loeffler and Ponting (1942). Daily fasting plasma levels of ascorbic acid, using blood samples obtained by fingerprick, were determined for each child by the micro-method of Farmer and Abt (1936).…”

Intubation Studies of the Human Small Intestine. Xxii. An Improved Technic for the Study of Absorption; Its Application to Ascorbic Acid

“…The amount in the plasma was determined by the titration procedure of Farmer and Abt (8,9) and by the photometric method of Mindlin and Butler (10). For the ascorbic acid content of the urine and intestinal specimens, samples were collected in flasks containing 10 cc.…”