Paired ion reversed-phase HPLC assay for the determination of iothalamic acid and para aminohippuric acid in urine.
A paired ion reversed-phase high performance liquid chromatographic method for simultaneous determination of iothalamic acid (Io) and para aminohippuric acid (PAH) in urine is described. The method uses a single internal standard for both drugs. The only sample preparation required is dilution of urine (1:100 or 1:500) with deionized water. The internal standard is added to a small aliquot of the diluted specimen and injected. For HPLC, a C8 column and a mobile phase consisting of potassium phosphate buffer with dodecyl triethylammonium phosphate IP reagent, 25% organic modifier with UV detection at 254 nm was used. Within day and between day variation for the assay were in the range of 1.48-9.46% for iothalamic acid and 1.84-10.36% for para aminohippuric acid for four levels of concentration. Limits of quantitation were 50.0 micrograms ml-1 for iothalamic acid and 75.0 micrograms ml-1 for para aminohippuric acid. Mean recovery was 98.55% for Io and 97.79% for PAH. This isocratic HPLC assay is simple, rapid and relatively inexpensive.
Clinical Research Unit, School of Pharmacy, University of California, San Francisco 94143-0622.
A K
AK
Seneviratne
A L
AL
Jayewardene
J G
JG
Gambertoglio
D002851:Chromatography, High Pressure Liquid; D005615:Freezing; D006801:Humans; D007202:Indicators and Reagents; D007483:Iothalamic Acid / Q000032:analysis*; D007674:Kidney Diseases / Q000378:metabolism / Q000652:urine; D017595:Renal Plasma Flow; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D010130:p-Aminohippuric Acid / Q000652:urine*
D007202:Indicators and Reagents; D007483:Iothalamic Acid; D010130:p-Aminohippuric Acid