Logo image
Structurally colored thin films of Ca2+-cross-linked alginate
Journal article   Peer reviewed

Structurally colored thin films of Ca2+-cross-linked alginate

Matthew D Cathell and Caroline L Schauer
Biomacromolecules, v 8(1)
Jan 2007
PMID: 17206785

Abstract

Alginates - chemistry Biocompatible Materials - chemistry Calcium - chemistry Calcium Chloride - chemistry Chromium - chemistry Cross-Linking Reagents - chemistry Cross-Linking Reagents - pharmacology Edetic Acid - chemistry Hydrogen-Ion Concentration Ions Macromolecular Substances - chemistry Metals - chemistry Polymers - chemistry Spectroscopy, Fourier Transform Infrared Surface Properties
Alginate, or alginic acid, is an unbranched binary copolymer of (1-->4)-linked beta-D-mannuronic acid and alpha-L-guluronic acid. Alginate readily forms binding interactions with a variety of divalent metal ions, such as calcium. This binding has been used to cross-link bulk alginates for a wide variety of applications, particularly in areas of tissue engineering, medical devices, and wound-healing dressings. A new method is identified here for producing Ca2+-cross-linked thin films of sodium alginate, using an aerosolized spray of CaCl2 solution. These thin films exhibit structural color that varies with film thickness. It is demonstrated that this structural color is highly reproducible and can also be tuned to produce a wide range of colored films. The noted ability of alginates to bind metal ions is used in combination with the structural coloration afforded by the thin film structure as a basis for color-based optical sensing of metal ions in aqueous solutions. Changes in film thickness, refractive index, and reflectivity in response to metal ions have been measured and reported. For certain ions such as Cr(III) and Cr(VI), changes in film thickness are the predominate factors in shifting the reflected film color. In the case of other ions such as Pb(II), a change in film refractive index plays a significant role in the reflectance properties of films.

Metrics

8 Record Views
62 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#11 Sustainable Cities and Communities
#6 Clean Water and Sanitation

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Web of Science research areas
Biochemistry & Molecular Biology
Chemistry, Organic
Polymer Science
Logo image