PC-300 preservative is a widely used bacteriostatic agent for in vitro diagnostic reagents. Its main active ingredients are a mixture of two isothiazolinones: 5-Chloro-2-methyl-4-isothiazolin-3-one (CMIT) and 2-Methyl-4-isothiazolin-3-one (MIT), with a content ratio of 3:1, and the total concentrati