Inorganic layered double hydroxides as ascorbic acid (vitamin C) delivery system--intercalation and their controlled...

Area of Science:

• Materials Science
• Chemistry
• Biochemistry

Background:

• Ascorbic acid (vitamin C) is vital but prone to degradation.
• Developing stable and controlled release methods for ascorbic acid is crucial for preserving its bioactivity.

Purpose of the Study:

• To prepare Zinc Iron (ZnFe) and Magnesium Iron (MgFe) layered double hydroxides (LDHs).
• To investigate the adsorption of ascorbic acid from aqueous solutions using these LDHs via anion exchange.
• To explore the potential for safe preservation and controlled release of ascorbic acid.

Main Methods:

• Synthesis of ZnFe- and MgFe-LDHs using the anion exchange method.
• Characterization of synthesized LDHs using X-ray Diffraction (XRD), Thermogravimetric Differential Thermal Analysis (TG-DTA), and Fourier-Transform Infrared (FT-IR) spectroscopy.
• Adsorption studies investigating parameters like pH, LDH amount, contact time, ascorbate concentration, and material composition.
• Analysis of adsorption kinetics and isotherms.
• Examination of ascorbic acid release behavior via deintercalation with carbonate anions.

Main Results:

• ZnFe-LDH-Cl and MgFe-Cl-LDH demonstrated rapid adsorption of ascorbic acid, reaching equilibrium within 60 minutes.
• Adsorption isotherms indicated specific interactions and high affinity between ascorbic acid and the LDHs.
• The study successfully demonstrated intercalation of ascorbic acid into the LDH gallery space.

Conclusions:

• ZnFe- and MgFe-LDHs are effective adsorbents for ascorbic acid.
• The anion exchange method provides a viable route for the preservation of ascorbic acid's bioactivity.
• Controlled release of ascorbic acid from LDHs is achievable through deintercalation.