Cryostructuring of Polymeric Systems. 57. Spongy Wide-Porous Cryogels Based on the Proteins of Blood Serum: Preparation, Properties and Application as the Carriers of Peptide Bioregulators.

Egor V Sidorskii,Vladimir I Lozinsky,Viktoria P Yamskova,Mikhail S Krasnov

doi:10.3390/gels6040050

Abstract

Wide-pore proteinaceous freeze–thaw spongy gels were synthesized via the cryotropic gelation technique using the bovine blood serum or its diluted solutions as the protein-containing precursors. The feed systems also included the denaturant (urea) and the thiol-reductant (cysteine). The gel-fraction yield decreased and the swelling degree of the walls of macropores in such heterophase matrices increased with decreasing the initial protein concentration. The optimum freezing temperature was found to be within a rather narrow range from −15 to −20 °C. In this case, the average size of the macropores in the resultant cryogels was 90–110 μm. The suitability of such soft wide-pore gel materials for the application as the carriers of peptide bioregulators was demonstrated in the in vitro experiments, when the posterior segments of the Pleurodeles waltl adult newts’ eyes were used as a model biological target. It was shown that a statistically reliable protective effect on the state of the sclera, vascular membrane and retinal pigment epithelium, as well as on the viability of fibroblasts, was inherent in the proteinaceous cryogels loaded with the peptide bioregulator (Viophtan-5™) isolated from the bovine eye sclera.

Highlights

A large number of various gel materials based on substances of a protein nature were used for a long time and are currently employed for biomedical purposes [1,2,3,4,5,6,7,8]
It was shown that a statistically reliable protective effect on the state of the sclera, vascular membrane and retinal pigment epithelium, as well as on the viability of fibroblasts, was inherent in the proteinaceous cryogels loaded with the peptide bioregulator (Viophtan-5TM) isolated from the bovine eye sclera
The wide-pore cryogels based on the blood serum proteins were prepared by a procedure similar to the method we applied earlier for the synthesis of the individual protein-derived cryogels [33,38]

Summary

Introduction

A large number of various gel materials based on substances of a protein nature were used for a long time and are currently employed for biomedical purposes [1,2,3,4,5,6,7,8]. Specific groups of the polypeptide- and protein-composed gels are those prepared in moderately-frozen systems via the so-called cryotropic gelation processes [11,12,13,14,15,16,17,18,19,20,21,22] that result in the formation of proteinaceous cryogels (e.g., see [10,23,24,25,26,27,28,29,30,31,32]) Among the latter gel matrices of certain applied interest are biodegradable wide-porous cryogels based on individual blood proteins or their natural (plasma, serum, cell lysate) and artificial mixtures [10,11,22,23,24,25,31,33,34,35,36,37]. (i) by the 3D coupling of the protein macromolecules with the aid of auxiliary cross-linking reagents added to the precursor solution directly prior to its cryogenic processing [10,11,22,23,24,25,29,30,31,34];

Methods

Results

Conclusion