Lactic acid (Standard) is the standard substance of Lactic acid, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Lactic acid (2-hydroxypropanoic acid), a glycolysis end product, is a hydroxycarboxylic acid receptor 1 (HCAR1) activator (EC50=4.2-5 mM). Lactic acid can be used as a hemodynamic index in critically ill patients and has anti-tumor activity.