Description_x000D_ General description_x000D_ p-Aminohippuric acid (PAH), a derivative of hippuric acid, is used in the measurement of renal plasma flow (RPF). Renal plasma flow measures the volume of plasma, which enters the kidney in a given period of time. To determine effective renal plasma flow, PAH is measured in a plasma sample (PPAH) and a urine sample (UPAH). The volume of urine flow (V) is also required._x000D_ Suitability_x000D_ Suitable for measuring PAH (p-Aminohippuric Acid) in plasma and urine samples_x000D_ Principle_x000D_ The PAH (p-Aminohippuric Acid) Assay kit can be used for measuring PAH in a plasma and urine samples. PAH reacts with 4-(dimethylamino)cinnamaldehyde (DACA) to generate a compound, which can be detected spectrophotometrically at 550 nm.