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Updated: Mar 30, 2026
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Preparation of Functional Silica Using a Bioinspired Method
Published on: August 1, 2018
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Instrument-free quantitative colorimetric analysis using adsorption-band length in a packed silica gel column.
Sychanh Phonxayxiong1, Takashi Kaneta1
1Department of Chemistry, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan.
Talanta
|March 28, 2026
Summary
This study introduces a simple, instrument-free colorimetric method using silica gel columns to measure analyte concentration by band length. This distance-based detection offers high sensitivity for analyzing iron and glutamic acid.
Area of Science:
- Analytical Chemistry
- Materials Science
Background:
- Conventional analytical methods often require complex instrumentation and multiple steps.
- Developing simple, sensitive, and portable analytical techniques remains a significant challenge in chemical sensing.
Purpose of the Study:
- To develop a novel, instrument-free colorimetric method for quantitative analysis.
- To establish distance measurement as a quantitative signal for colorimetric detection.
- To validate the method's sensitivity and applicability for detecting specific analytes.
Main Methods:
- Utilized a packed miniature silica gel column as a signal transducer.
- Analyte concentration was determined by measuring the length of a colored adsorption band.
- Developed a theoretical model to correlate solute concentration, adsorption, and band propagation.
- Validated the method for iron(II) ion and enzyme-mediated glutamic acid detection.
Main Results:
- Demonstrated a proportional relationship between analyte concentration and colored band length.
- Achieved sensitivity comparable to spectrophotometry for iron(II) detection (LOD 0.20 μM).
- Showcased superior sensitivity for glutamic acid detection (LOD 0.08 μM) compared to microplate reader methods.
- Successfully quantified trace iron in tap water with high recovery.
Conclusions:
- The developed method provides a simple, instrument-free, and highly sensitive analytical platform.
- Distance measurement serves as an effective quantitative signal in colorimetric detection.
- This approach integrates preconcentration with a distance-based readout for enhanced analysis.
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