Start Publications Proteolytic degradation of gelatin-tannic acid multilayers
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Proteolytic degradation of gelatin-tannic acid multilayers

Year: 2018

Journal: J. Colloid Interface Sci., Volume 526, SEP 15, page 244–252

Authors: Bahmanzadeh, Safiyeh; Ruzgas, Tautgirdas; Sotres, Javier

Keywords: Gelatin; Tannic acid; Biodegradable films; Edible films; Proteases; Electrochemical Impedance Spectroscopy; Quartz Crystal Microbalance with Dissipation

Hypothesis: Gelatin is one of the most popular constituents of biodegradable/edible films. Because of its poor mechanical properties, it typically needs to be cross-linked. In this regard, the use of tannic acid has attracted significant interest. Whereas the biodegradability of gelatin is well established, little is known on how different cross-linking methods affect biodegradability. In most cases, the ionic strength at which protein films are grown has a drastic effect on their structure. Thus, it is expected that by controlling the ionic strength during the growth of cross-linked gelatin films it should be possible to tune the access to relevant cleavage sites by proteases and, therefore, their biodegradability. Experiments: Gelatin-tannic acid were grown at different ionic strengths by means of the layer-by-layer self-assembly method. The growth of these multilayers and their response to the presence of different proteases were monitored by means of Electrochemical Impedance Spectroscopy and Quartz Crystal Microbalance with Dissipation. Findings: Gelatin-tannic acid multilayers grown at low ionic strength exhibited a swollen structure that allowed easy access to their cleavage sites by proteases. Multilayers formed at physiological ionic strength exhibited a compacter structure, which limited their proteolytic degradation. (C) 2018 The Author(s). Published by Elsevier Inc.