Development and validation of an HPLC-UV method for iodixanol quantification in human plasma
Iodixanol is a widely used iso-osmolar contrast medium agent. Similar to iohexol, it can also be a good
exogenous marker for the measurement of glomerular filtration rate (GFR). This article describes the
development and validation of an HPLC-UV method for quantification of iodixanol in human plasma.
Internal standard, iohexol (20l, 1 mg/ml), and perchloric acid (30l, 20%, v/v) were added to plasma
samples (300l), followed by neutralization with 10l potassium carbonate (5 M). Samples were centrifuged
and 10l of the supernatant was injected onto a C18 EPS analytical column (3m particle size,
150mm×4.6 mm). The extraction method yielded >95% recovery for both iodixanol and iohexol. The
mobile phase consisted of 0.1% (w/v) sodium formate buffer and acetonitrile. Iohexol and iodixanol peaks
were eluted at ~5 and 9 min, respectively using a fast gradient method. The assay lower limit of detection
was 2.0g/ml and lower limit of quantificationwas 10g/ml. The calibration curves, assessed in six replicates,
were linear over an iodixanol concentration range of 10–750g/ml. Intra- and inter-day accuracy
was >95% and precision expressed as % coefficient of variation was <10%. This method is simple, accurate,
precise and robust and can potentially be used for iodixanol quantification in large-scale clinical studies.