PVA/STMP based hydrogels as potential substitutes of human vitreous

Abstract

PVA based hydrogels were synthesised using, as crosslinking agent, trisodium trimetaphosphate (STMP) to obtain potential substitutes for the vitreous body of the eye. The hydrogels, obtained using different amounts of STMP, were characterised by Infrared Spectroscopy which confirmed the successful occurrence of crosslinking reaction. The mechanical spectra of the fully hydrated samples confirmed covalently crosslinked systems (i.e. G' > G''). The rheological analysis pointed out that only one of the hydrogels (PVA STMP 8:1) showed a behaviour similar to that of human vitreous. The hydrogel was also subjected to injection through a small needle, a procedure that is essential in the use of vitreous substitutes. Further analysis in terms of light transmittance, water content measurements, diffusion coefficient and cytotoxicity confirmed the applicability of such a hydrogel as vitreous substitute.

Mechanism of Aqueous Humor Secretion, Its Regulation and Relevance to Glaucoma

“…The vitreous is probably not a tissue in proper sense, but rather a highly specialized extracellular fluid containing connective tissue-specific elements, such as collagen fibers, hyaluronic acid (hyaluronan) and some other soluble proteins and glycoproteins. Its density, refractive index and pH is slightly higher than those of pure water (Gloor, 1987;Redslob, 1932) and its water content is extremely high, between 98% (Leone et al, 2010;Redslob, 1932) and 99.7% (Sullmann, 1951). The mechanical stability and optical transparency of the vitreous comes from the specific organization of the collagen-hyaluronan network.…”

States of water, surface and rheological characterisation of a new biohydrogel as articular cartilage substitute

“…[25,16] In this paper we utilised it as crosslinking agent. To guarantee this action a 5% concentration of the polymer solution was chosen.…”

“…The obtained soft film was rinsed with large volumes of distilled water and further dried until no weight loss could be detected. [16] The hydrogel morphology was modified realising a porous structure (PVA11p) following a previously reported procedure using a cell-culture strainer with a 100 mm mesh. [17] Chemical characterization Infrared analysis.…”

Künstlicher Glaskörper

“…Zu den in Erprobung befindlichen synthetischen Substraten zählen unter anderem Polyvinylpyrrolidon [10], Polyvinylalkohole [13], Polyacrylamid [29], Polyglycerin-Methylacrylat [6], Polyethylenglykol [31] und Hydroxypropylmethylcellulose [8].…”