Thermo Scientific offers a ready-made pH/ionic strength adjustor solution that adjusts the pH of standards and samples used in ammonia measurements. The ISA includes a pH color indicator for instant verification of correct pH. The accuracy of the results is improved, because the solution both prevents complexation of ammonia and inhibits formation of metal hydroxides allowing determination of total ammonia in the sample. Order pH Adjustor/ISA for Ammonia (951211!), containing one 475 mL bottle of ammonia pH adjusting ISA. 

! - Signifies a hazardous solution.