Fluorometric and colorimetric platforms for rapid and sensitive hydroxychloroquine detection in aqueous samples

Area of Science:

• Analytical Chemistry
• Biochemistry
• Materials Science

Background:

• Pharmaceutical detection is crucial for monitoring, manufacturing, and diagnostics.
• The COVID-19 pandemic heightened the need for Hydroxychloroquine (HCQ) detection due to increased usage.
• Existing detection methods may lack the speed, sensitivity, or practicality required for certain applications.

Purpose of the Study:

• To develop rapid, sensitive, and selective optical detection platforms for Hydroxychloroquine (HCQ).
• To utilize the interactions between Thioflavin T (ThT) and G-quadruplex DNA, and silver nanoparticle aggregation for HCQ sensing.
• To validate the practical applicability of these methods in complex biological matrices.

Main Methods:

• Fluorometric detection leveraging the fluorescence quenching of Thioflavin T (ThT) in the presence of HCQ and Tel24 G-quadruplex DNA.
• Colorimetric detection based on HCQ-induced aggregation of citrate-capped silver nanoparticles (Cit-AgNPs) in a saline environment.
• Optimization of reaction conditions and assessment of selectivity against similar small molecules.

Main Results:

• The fluorometric method showed a linear range of 0.24-5.17 μM with a detection limit of 120 nM.
• The colorimetric method demonstrated a linear range of 18.0-240.0 nM and a detection limit of 9.2 nM.
• Both methods exhibited good selectivity and achieved high average recoveries (75.4-110.2% and 86.9-98.2%) in spiked human urine samples.

Conclusions:

• Developed fluorometric and colorimetric platforms provide rapid and sensitive detection of HCQ.
• The methods are selective and applicable to complex matrices like human urine.
• These optical sensors offer a promising approach for HCQ monitoring in various settings.