Vitamin methods

Abstract
A further comparison was made of the results obtained by the improved thiochrome method of Wang and Harris with those obtained by biological tests (bradycardia method). On one specimen of urine the biological value was 110% of the chemical and on another 101%; in earlier tests the values were 100, 121, 100, 89, 128%; avg. for both series 107%. Recovery tests confirmed the reliability of the method.