Drug Release from New Bioartificial Hydrogel

Abstract

The use of high water content (> 96%) hydrogels obtained from copolymerisation of bovine serum albumin and poly(ethylene glycol) as a controlled release system has been investigated. Such hydrogels allowed release of soluble and hydrophobic substances, even proteins. Release is shown to occur by a diffusion controlled mechanism, leading to half-life times of release ranging between 0.8 hour for theophylline and 4.2 hours for lysozyme, when a 2.4 mm thick disc of BSA-PEG (MW of 10000) was used. The effect of the porosity of the hydrogel on the diffusive properties of theophylline and hydrocortisone has been evaluated by varying the molecular weight of the poly(ethylene glycol). It was shown that poly(ethylene glycol) of high molecular weight leads to more porous hydrogels in which the diffusion is faster.

Polymer-conjugated albumin and fibrinogen composite hydrogels as cell scaffolds designed for affinity-based drug delivery

“…Subsequently, other proteins have also been PEGylated in order to prolong their residence time in the blood stream by improving their physical and thermal stability, increasing their protection against proteolysis and decreasing their clearance from the body [9,10]. PEGylated albumin hydrogels for drug delivery applications have also recently been described by two groups [11][12][13], however, in these studies the drug release rates from the hydrogels were dominated by Fickian diffusion and not controlled by the specific affinity of the various tested drugs for the albumin constituent.…”

Biosynthetic hydrogels—Studies on chemical and physical characteristics on long‐term cellular response for tissue engineering

“…Biosynthetic hydrogels can exhibit structural, physiochemical, mechanical, and biological functionalities and controlled degradation profile . Several combinations of biosynthetic hydrogels have been studied for various biomedical applications like tissue engineering, drug delivery, gene delivery, and so forth. Biosynthetic glycidyl methacrylate and hyaluronic acid, poly(ethylene glycol)–fibrinogen conjugates, poly(ethylene glycol) and heparin, poly vinyl alcohol, gluteraldehyde, chitosan, dextran, polyethylene glycol–chitosan, poly acrylic acid–alginate, chitin–PLGA, PAA–chitosan and PMAA–alginate were reported for various biomedical applications.…”

Photopolymerizable Hydrogels Made from Polymer‐Conjugated Albumin for Affinity‐Based Drug Delivery

“…There have been many attempts in the past to use PEG and albumin for a number of different applications. [13][14][15][16][17][18] Specifically, attempts to conjugate PEG to albumin were made for reducing bovine serum albumin immunogenicity, [19] for lipid factor delivery, [20] and as a model of protein delivery from PEG hydrogels. [21] Although PEG is most frequently used to conjugate biomolecules in order to achieve a decrease in immunogenicity and an increase in body-residence-time, [22] PEG's unique properties are also suited for drug delivery applications.…”

“…Other attempts to conjugate albumin and PEG for drug delivery made by Fortier and coworkers resulted in a hydrogel that was characterized by Fickian diffusion controlled drug release kinetics, and included toxic unreacted amine-reactive di-functional PEG groups that required extensive washes to remove. [17] We have recently developed an alternative approach to create a photopolymerizable hybrid hydrogel made of PEG conjugated to albumin for tissue engineering. [24] We now examine the possibility of using our PEG-albumin system as a biocompatible, affinity-based drug delivery matrix.…”