Solid-State Preparation and Characterization of 2-Hydroxypropylcyclodextrins-Iodine Complexes as Stable Iodophors

Area of Science:

• Pharmaceutical Chemistry
• Materials Science
• Microbiology

Background:

• Traditional iodine antiseptics suffer from poor water solubility and high volatility.
• Existing stable solid iodine formulations, like povidone-iodine, are limited.
• Development of novel, stable, and water-soluble solid iodophors is crucial.

Purpose of the Study:

• To prepare and characterize solid inclusion complexes of molecular iodine with hydroxypropyl-substituted cyclodextrins (α, β, γ).
• To evaluate the iodine content, stability, and complex formation of these novel iodophors.
• To assess the bactericidal efficacy of the prepared cyclodextrin-iodine complexes.

Main Methods:

• Solid inclusion complexes prepared using liquid-assisted grinding, co-evaporation, and sealed heating.
• Iodine content and stability assessed via a validated UV spectrophotometric method.
• Complex formation confirmed by thermal analysis (DSC/TGA), SEM/EDX, and XPS.

Main Results:

• High iodine content (8.3-10.8%) achieved in all cyclodextrin complexes.
• Preparation method influenced iodine content and complex characteristics.
• 2-hydroxypropyl-α-cyclodextrin complexes exhibited superior stability.
• All complexes demonstrated bactericidal activity against Staphylococcus epidermidis.

Conclusions:

• Hydroxypropyl cyclodextrin-iodine complexes represent promising stable, solid iodophors.
• These novel formulations overcome solubility and volatility issues of elemental iodine.
• The complexes show potential for antiseptic applications, particularly against S. epidermidis.