GLC determination of urinary chlorthalidone levels

Area of Science:

• Analytical Chemistry
• Pharmacokinetics
• Clinical Diagnostics

Background:

• Accurate measurement of chlorthalidone is crucial for therapeutic drug monitoring.
• Existing methods may lack the sensitivity required for low-dose clinical studies.

Purpose of the Study:

• To develop a sensitive and specific gas-liquid chromatography (GLC) method for determining urinary chlorthalidone levels.
• To validate the method's suitability for analyzing human urine samples from patients receiving clinical doses.

Main Methods:

• On-column methylation of chlorthalidone using trimethylanilinium hydroxide in methanol.
• Gas-liquid chromatography (GLC) for separation and detection of the methylated derivative.

Main Results:

• The developed GLC method demonstrated high sensitivity and specificity.
• The method can accurately determine chlorthalidone levels as low as 0.1 microgram/ml in dog urine.
• The technique is deemed adequate for analyzing human urine samples from clinical trials.

Conclusions:

• A novel and robust GLC method for urinary chlorthalidone analysis has been established.
• This method provides a sensitive tool for pharmacokinetic studies and therapeutic drug monitoring.
• The assay's sensitivity supports its application in human clinical settings.