A fast method for the detection of irinotecan in plasma samples by combining solid phase extraction and differential...

Area of Science:

• Analytical Chemistry
• Clinical Chemistry
• Pharmacology

Background:

• Irinotecan (CPT-11) is a vital chemotherapy drug for solid tumors.
• Accurate monitoring of CPT-11 plasma levels is crucial for effective cancer treatment.
• Existing detection methods may lack speed or specificity for clinical settings.

Purpose of the Study:

• To develop and validate a rapid and reliable method for quantifying irinotecan (CPT-11) in human plasma.
• To assess the method's suitability for monitoring CPT-11 levels during chemotherapy.
• To ensure the method effectively removes interfering substances commonly co-administered with CPT-11.

Main Methods:

• Solid phase extraction (SPE) using acetonitrile as eluent for CPT-11 isolation from plasma.
• A cleaning step was incorporated to remove endogenous compounds and co-therapeutics (5-FU, FA).
• Electrochemical detection via differential pulse voltammetry at a glassy carbon electrode (GCE) in a basic acetonitrile medium.

Main Results:

• A well-defined oxidation peak for CPT-11 was achieved, free from interference from metabolites.
• The method demonstrated good linearity with a limit of detection (LOD) of 1.10 × 10⁻⁷ M and a limit of quantification (LOQ) of 3.74 × 10⁻⁷ M.
• Successful determination of CPT-11 concentrations in plasma samples from an oncology patient at 30 and 180 minutes post-infusion.

Conclusions:

• The developed SPE-electrochemical detection method offers a fast and accurate approach for CPT-11 analysis in plasma.
• This method shows significant potential for routine clinical application in cancer patient management.
• The technique effectively addresses challenges of interference from co-administered drugs and endogenous compounds.