title: The quantitative estimation of diphtheria and tetanus toxoids. 1. The flocculation test and the Lf-unit.
abstract: Considerable confusion exist in the quantitative estimation of diphtheria and tetanus toxoids. The present paper is the first in a series of papers comparing various quantitative methods. It describes the flocculation test, gives a mathematical model for the three-dimensional reaction surface, and suggests different designs which facilitate the unbiased calculation of the end-point.
mesh_terms: D000704:Analysis of Variance; D004168:Diphtheria Toxoid / Q000032:analysis*; D005428:Flocculation Tests; D008433:Mathematics; D013745:Tetanus Toxoid / Q000032:analysis*
chemical_list: D004168:Diphtheria Toxoid; D013745:Tetanus Toxoid