Reagents are compounds used in controlled laboratory experiments to cause chemical reactions. There are many types of reagents, from common ones like ammonia to more specialized ones like transfection reagents. Reagent suppliers must carefully evaluate, store, and source the reagents they provide to ensure they are of high quality and will perform as intended in experiments. Suppliers need to purchase reagent-grade compounds and check the legitimacy and reviews of their reagent distributors to guarantee satisfied customers. They also use methods like blogs and websites to provide information on reagents and receive feedback.