Urinary l-kynurenine quantification and selective extraction through a molecularly imprinted solid-phase extraction...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Pharmacology

Background:

• l-Kynurenine is an endogenous metabolite from l-tryptophan catabolism.
• It shows potential as a biomarker for evaluating checkpoint inhibitor efficacy in antitumor therapy.
• l-Kynurenine is also explored for its therapeutic potential in autoimmune disorders.

Purpose of the Study:

• To develop a specific molecularly imprinted polymer for l-kynurenine recognition.
• To establish an innovative solid-phase extraction (SPE) method for l-kynurenine quantification in human urine.
• To assess the feasibility of the developed method for pharmaceutical applications.

Main Methods:

• Synthesis of a molecularly imprinted polymer tailored for l-kynurenine.
• Application of the polymer in an off-line solid-phase extraction technique.
• Validation of the method using standard solutions and fortified human urine samples.

Main Results:

• High recoveries achieved: up to 97.7% for standards and 84.1% for urine samples.
• Excellent linearity demonstrated in the range of 0.157–20 μg/mL (r² = 0.9992).
• Successful quantification of low l-kynurenine concentrations (0.80 μg/mL) in human urine.

Conclusions:

• The developed SPE method using a specific molecularly imprinted polymer is effective for l-kynurenine extraction and quantification in human urine.
• This method shows good feasibility for biological samples and aids in identifying potential drug candidates.
• The technology holds promise for pharmaceutical industries in l-kynurenine production for autoimmune disorder treatments.