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Embedded microdrops configuration for diffusion-based colorimetric reactions: a novel approach for thiol
Archana Jain1, Manju Gupta2, Krishna K Verma2
1Department of Chemistry, Mangalayatan University, Jabalpur 483001, Madhya Pradesh, India.
Analytical Methods : Advancing Methods and Applications
|November 18, 2024
Summary
A novel Extractive Reactions in Embedded Drops (EXRED) method enhances thiol determination using micro-colorimetry. This technique offers improved sensitivity and efficiency for analyzing thiols in samples.
Area of Science:
- Analytical Chemistry
- Spectroscopy
Background:
- Micro-colorimetry offers a sensitive approach for chemical analysis.
- Traditional methods for thiol determination can be limited by sensitivity and sample preparation.
Purpose of the Study:
- To introduce and validate a new micro-colorimetric technique, Extractive Reactions in Embedded Drops (EXRED), for thiol analysis.
- To enhance the sensitivity and efficiency of thiol determination compared to classical methods.
Main Methods:
- Developed the EXRED technique using a reagent drop surrounded by an organic solvent film within a microsyringe.
- Applied EXRED for the determination of thiols using the Ellman reagent and micro-spectrophotometry.
- Optimized reaction parameters using response surface methodology.
Main Results:
- EXRED achieved molar absorptivities 3-28 times higher than the classical Ellman reaction.
- Established calibration ranges of 5-700 μM and 2-60 μM for different EXRED configurations.
- Obtained averaged LOD/LOQ values of 0.048/0.16 μM, demonstrating high sensitivity.
- EXRED methods aligned with green analytical chemistry principles.
Conclusions:
- EXRED is a highly sensitive and efficient micro-colorimetric method for thiol determination.
- The technique offers significant advantages over classical methods in terms of sensitivity and analytical performance.
- EXRED represents a sustainable and green analytical approach.
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