Final answer:
Indigotindisulfonate sodium's specific use isn't mentioned in the reference material provided, which focuses on various other chemicals and their applications.
Step-by-step explanation:
Indigotindisulfonate sodium, often associated with medical procedures and applications, is not covered in the provided reference information. The reference material addresses various chemicals and their uses for different applications, such as bleaching agents like sulfur dioxide for wool, sodium borohydride in water purification, iodine and povidone-iodine for disinfection, and sodium hydroxide for manufacturing soaps and detergents. It also mentions the use of certain compounds as ingredients in laxatives, antacids, and deodorants. However, these do not directly correspond to indigotindisulfonate sodium.