Article

Leach JB and Schmidt CE: ‘Characterization of protein release from photocrosslinkable hyaluronic acid-polyethylene glycol hydrogel tissue engineering scaffolds’, Biomaterials, , 26

Department of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Biomaterials (Impact Factor: 8.56). 01/2005; 26(2):125-35. DOI: 10.1016/j.biomaterials.2004.02.018
Source: PubMed

ABSTRACT

The goal of this work was to utilize the naturally derived bioactive polymer hyaluronic acid (HA) to create a combination tissue engineering scaffold and protein delivery device. HA is a non-immunogenic, non-adhesive glycosaminoglycan that plays significant roles in several cellular processes, including angiogenesis and the regulation of inflammation. In previous work, we created photopolymerizable glycidyl methacrylate-hyaluronic acid (GMHA) hydrogels that had controlled degradation rates, were cytocompatible, and were able to be modified with peptide moieties. In the present studies, we characterized the release of a model protein, bovine serum albumin (BSA), from GMHA and GMHA-polyethylene glycol (PEG) hydrogels. Although BSA could be released rapidly (> 60% within 6 h) from 1% GMHA hydrogels, we found that increasing either the GMHA or the PEG concentrations could lengthen the duration of protein delivery. Preliminary size exclusion chromatography studies indicated that the released BSA was almost entirely in its native monomeric form. Lastly, protein release was extended to several weeks by suspending BSA-poly(lactic-co-glycolic acid) microspheres within the hydrogel bulk. These initial studies indicate that the naturally derived biopolymer HA can be employed to design novel photopolymerizable composites that are suitable for delivering stable proteins from scaffolding in tissue engineering applications.

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    • "Due to the nonspecific reactions of free radicals and the large number of free amines available in growth factors, free radical and aldehyde reaction strategies, respectively, are unsuitable for growth factor delivery due to potential denaturation of the growth factor, unless the growth factor is protected in some fashion. This protection could be afforded through incorporation into a hydrophobic polymer microsphere [25] [26], solid lipid particle [27], or through distribution of the protein as a poorly soluble salt particle [28]. Furthermore, despite the high yield, specific reaction afforded by Diels–Alder reactions, which occur under mild aqueous conditions, gelation times are inordinately long [29]. "
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    • "Several HA derivatives have been developed for drug delivery [10], mainly for its potential as a biodegradable carrier [11]. Some authors have reported the use of this polymer for different proteins, drugs [12], peptides [13] or for gene delivery [14] [15] using HA as a depot system [16], as hydrogels (physically and chemically cross-linked) [17] [18] [19] or as nano-or micro-particulate systems [20] [21]. Studies related to biocompatibility and biodegradability [22] have supported the use of HA as a promising biomaterial to design modified drug delivery systems. "
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    • "Hydrogels have been known to be effective carriers of drugs for cell-based drug delivery applications (Schmidt et al. 2008). One such representative is a hydrogel with Hyaluronic acid-based (HA) hydrogels which was specifically designed for the regeneration of different types of tissues (Leach and Schmidt 2005). TaO x can be cross-linked with the HA hydrogel to create a composite that can be used for efficient cell or drug delivery, where TaO x acts as the contrast agent allowing to monitor biodistribution and half-life of bioactive compartments. "
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