Molecularly-imprinted pumice as a selective solid-phase extraction adsorbent for kojic acid determination in cosmetic...

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Kojic acid (KA) is widely used in cosmetics for skin lightening.
• Accurate determination of KA in cosmetic products is essential for quality control and safety.
• Existing methods for KA analysis may lack selectivity or require complex sample preparation.

Purpose of the Study:

• To develop a highly sensitive and selective adsorbent for kojic acid (KA) extraction.
• To utilize molecularly-imprinted pumice (MIP-PMC) for solid-phase extraction (SPE) of KA from cosmetic samples.
• To establish an efficient analytical method for KA determination in cosmetic products.

Main Methods:

• Surface imprinting method was employed to synthesize molecularly-imprinted pumice (MIP-PMC).
• MIP-PMC was characterized to confirm the polymer layer formation and properties.
• Solid-phase extraction (SPE) using MIP-PMC was optimized for KA separation.
• Kojic acid was quantified using ultraviolet-visible (UV-vis) spectrophotometry and validated with HPLC.

Main Results:

• MIP-PMC exhibited a high adsorption capacity (89.9 mg/g) and fast adsorption equilibrium (30 min).
• An imprinting factor of 3.28 demonstrated significant selectivity of MIP-PMC for KA.
• The developed method showed excellent linearity (0.04-400 mg/L), precision (<5%), and recovery (98.0-100.4%).
• A low limit of detection (LOD) of 12.8 μg/L and a preconcentration factor of 4 were achieved.

Conclusions:

• The tailored MIP-PMC is an effective adsorbent for selective and rapid SPE of kojic acid.
• The integrated MIP-PMC SPE and UV-vis spectrophotometry method provides a highly efficient approach for KA analysis in cosmetics.
• This method offers a sensitive, accurate, and reliable solution for sample pretreatment and determination of KA in real cosmetic samples.