Analytical techniques for furosemide determination

Due to the clinical importance of furosemide, a large number of analytical procedures to detect the presence of this drug in pharmaceutical and physiological samples has been developed. In this manuscript, a review of the most frequent analytical techniques described to determine furosemide is presented. Special attention has been paid to spectrophotometric and chromatographic techniques, but also to relevant methods using capillary electrophoresis or flow-injection analysis, as well as the detection modes coupled to these techniques. The review also focuses on the different degradation pathways of the drug and cautions to prevent it, otherwise rarely or confusedly mentioned in the analytical reports. Some guidelines about purification of the raw product after synthesis are also addressed.