Sulfosalicylic acid is used in urine tests to determine urine protein content. The chemical causes the precipitation of dissolved proteins, which is measured from the degree of turbidity.Sulfosalicylic acid , Family Practice Notebook website
It is also used for integral colour anodizing.
With water it is used as a shuttle solution for the CAS assay to test for siderophore.
See also Salicylic acid
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