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Digital image method based on a smartphone assisted by hydrophobic natural deep eutectic solvent for iron
Gabriel Bercley de Lima Vitorino1, Jackson Rodrigo Dos Santos Silva1, Vinícius de Alcântara Carvalho1
1LIA3-Applied Analytical Instrumentation Laboratory, Department of Fundamental Chemistry, Federal University of Pernambuco, Av. Jornalista Anibal Fernandes, S/N, Cidade Universitária, Recife, 50740-560, PE, Brazil. vagner.bsantos@ufpe.br.
A new green analytical method uses natural deep eutectic solvents (NADES) and smartphone colorimetry for iron (Fe) detection in dietary supplements. This cost-effective, portable approach ensures supplement safety and effectiveness without hazardous chemicals.
Area of Science:
- Analytical Chemistry
- Green Chemistry
Background:
- Dietary supplement quality control is crucial for public health.
- Conventional analytical methods often involve toxic solvents and complex instrumentation, leading to environmental concerns and high costs.
- There is a need for sustainable, efficient, and accessible analytical techniques.
Purpose of the Study:
- To develop and validate an innovative, environmentally friendly analytical method for iron (Fe) quantification in dietary supplements.
- To utilize natural deep eutectic solvents (NADES) combined with smartphone-based colorimetric detection.
- To establish a green, cost-effective, and portable method for quality control.
Main Methods:
- Formulation of a hydrophobic NADES using menthol and dodecanoic acid.
- Development of a selective Fe3+ extraction using the NADES and an ion-pair complex (SDBS-MB) colorimetric reagent.
- Validation of the method using smartphone colorimetry and comparison with UV-vis spectrophotometry.
Main Results:
- The NADES-assisted colorimetric method achieved a limit of detection (LOD) of 31 µg L-1 and a limit of quantification (LOQ) of 103 µg L-1.
- High recoveries (92.0%–106%) and statistical equivalence to UV-vis methods were observed for Fe analysis in dietary supplements.
- The method demonstrated high selectivity for Fe in complex matrices and achieved a green score of 0.84.
Conclusions:
- The developed method is a highly selective, sensitive, portable, and cost-effective approach for Fe quantification.
- This green analytical method significantly advances sustainable practices in quality control for dietary supplements.
- The methodology holds potential for application in analyzing other matrices, promoting wider adoption of eco-friendly analytical techniques.
