Polymeric Iodophors: Preparation, Properties, and Biomedical Applications

Abstract

The review summarizes the data on the main chemical and physiological properties of iodine and its capability of complexation with natural and synthetic polymers. Iodine is the best known antiseptic used to prevent and treat microbial infections. Its unique capability of complexation with certain polymers opens wide opportunities for targeted and prolonged delivery to target organs. Polymeric complexes with iodine have another color, other morphology, a higher electrical conductivity, and higher biological activity as compared with initial polymers. The formation of and ions is associated with iodine-polymer complexation. Iodine-containing biocompatible adhesive controlled-release formulations are designed as part of research into iodine-polymer complexes. The field is promising in terms of treating certain diseases because tolerance to iodine compounds does not usually develop in microbial cells.

Keywords: antimicrobial activity; antiseptics; biological activity; iodine–polymer complexes; iodophors.

Fig. 1.

Temperature dependences of iodine solubility in (1) water and (2) 0.1 g/L potassium iodide. Data to plot the dependences were taken from [4].

Fig. 2.

Absorption spectra of tetrabutylammonium iodide, tetrabutylammonium triiodide, and iodine radical anions in acetonitrile. Reproduced from [15] with permission from the American Chemical Society.

Fig. 3.

Absorption spectra of (1) 0.003 and (2) 0.00375% iodine (aqueous solutions) in the presence of (1) 0.0225 or (2) 0.0005% potassium iodide.

Fig. 4.

Absorption spectra of (1) 0.00168% PVP–iodine and (2) 0.003% iodine (aqueous solution) with 0.0225% potassium iodide. The inset shows the (1) PVP–iodine and (2) iodine–iodide solutions.

Fig. 5.

The aggregate model of PVA–iodine complexes. Reproduced from [29] with permission from John Wiley and Sons.

Fig. 6.

PVP–iodine complex. Reproduced from [33] with permission from the American Chemical Society.

Fig. 7.

Structures of (a) amylose and (b) amylopectin

Fig. 8.

Chitosan structure.

Fig. 9.

Effect of pH on the turbidity of aqueous solutions of (1) chitosan, (2) fully deacetylated chitosan, and (3) half-acetylated chitosan. Curve (4) was obtained for precipitated chitosan after its repeated dissolution. Reproduced from [52] with permission from Wiley and Sons.

Fig. 10.

Color of (1) a chitosan–iodine complex and (2) an iodine solution (a) before and (b) after freezing.

Fig. 11.

Structures of (a) cellulose and (b) ethylcellulose.

Fig. 12.

Effect of pH on iodine release. Reproduced from [82] with permission from Elsevier.

Fig. 13.

Bactericidal effect of composite membranes based on chitosan/PEG/multi-walled carbon nanotubes and impregnated with iodine (CM-0, CM-0.10, CM-0.17, and CM-0.31) against E. coli and S. aureus. Reproduced from [85] with permission from Elsevier.

Fig. 14.

Iodine release from (2) PVP–iodine and the thiolated PVP–iodine complexes (3) PVP-1, (4) PVP-2, and (5) PVP-3. Control curve 1 was obtained with free iodine. Reproduced from [89] with permission from the American Chemical Society.

Fig. 15.

Viability of human foreskin fibroblasts treated with an extract of sodium alginate/povidone–iodine for 24 h as compared with a control sample (100%). Reproduced from [107] with permission from Elsevier.

Fig. 16.

Antibacterial activity of poly(N-PV–PA)–iodine and poly(N-PV–PA) against (a) E. coli and (b) S. aureus. Reproduced from [104] with permission from Elsevier.