Preconcentration of indapamide from human urine using molecularly imprinted solid-phase extraction

Area of Science:

• Analytical Chemistry
• Polymer Science
• Pharmacokinetics

Background:

• Accurate quantification of pharmaceuticals in biological matrices is crucial for therapeutic drug monitoring.
• Existing methods for indapamide analysis may lack the required sensitivity or selectivity.
• Molecularly imprinted polymers (MIPs) offer a promising approach for selective analyte recognition.

Purpose of the Study:

• To develop and validate a simple, sensitive, and selective method for indapamide extraction and preconcentration from human urine.
• To utilize molecularly imprinted solid-phase extraction (MISPE) coupled with spectrophotometry for indapamide determination.
• To assess the efficiency and reliability of the developed MISPE-spectrophotometric method.

Main Methods:

• Synthesis of MIPs using indapamide as a template via a non-covalent imprinting approach.
• Preparation of MISPE cartridges packed with MIPs and non-imprinted polymers (NIPs).
• Spectrophotometric determination of indapamide in eluates from MISPE cartridges.

Main Results:

• The developed method achieved a preconcentration factor of 16.30, with a limit of detection (LOD) of 0.025 μg/mL and a limit of quantification (LOQ) of 0.075 μg/mL.
• A high imprinting factor (9.3) and good recovery rates (80.1-81.2%) for indapamide in human urine were obtained.
• Excellent precision was demonstrated with low within-day (0.17-0.42%) and between-day (1.1-1.4%) variability.

Conclusions:

• The proposed MISPE-spectrophotometric method is effective for the selective extraction, preconcentration, and determination of indapamide in human urine.
• The method demonstrates high sensitivity, selectivity, and reproducibility, making it suitable for clinical and research applications.
• This technique provides a valuable tool for pharmacokinetic studies and therapeutic drug monitoring of indapamide.