Search

Background: Collagen-based films including casings with a promising application in meat industry are still needed to improve its inferior performance. In the present study, the reinforcement of carboxylated cellulose nanofibers (CNF) for collagen film, based on inter-/intra- molecular electrostatic interaction between cationic acid-swollen collagen fiber and anionic carboxylated CNF, was investigated., Results: Adding CNF decreased the zeta-potential but increased particle size of collagen fiber suspension, with little effect on pH. Furthermore, CNF addition led to a higher tensile strength but a lower elongation, and the water vapor and oxygen barrier properties were improved remarkably. Because the CNF content was 50 g kg -1 or lower, the films had a homogeneous interwoven network, and CNF homogeneously embedded into collagen fiber matrix according to the scanning electron microscopy and atomic force microscopy analysis. Additionally, CNF addition increased film thickness and opacity, as well as swelling rate., Conclusion: The incorporation of CNF endows collagen fiber films good mechanical and barrier properties over a proper concentration range (≤ 50 g kg -1 collagen fiber), which is closely associated with electrostatic reaction of collagen fiber and CNF and, subsequently, the form of the homogenous, compatible spatial network, indicating a potential applications of CNF in collagenous protein films, such as edible casings. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

Aiming to mimic a blood vessel structurally, morphologically, and mechanically, a sequential electrospinning technique using a small diameter mandrel collector was performed and a three-layered tubular scaffold composed of nanofibers of polycaprolactone, collagen, and poly(l-lactic acid) as inner, intermediate, and outer layers, respectively, was developed. Biological performances of the scaffold in terms of compatibility with blood and endothelial cells were assessed to get some insights into its potential use as a tissue engineered small-diameter vascular replacement compared to an expanded polytetrafluoroethylene vascular graft. Due to direct contact of the blood and endothelial cells with inner surface of the scaffold, polycaprolactone fibers were characterized using SEM, water contact angle measurement, and ATR-FTIR. Despite similar surface wettability of the electrospun scaffold and the expanded polytetrafluoroethylene graft, the three-layered scaffold significantly reduced platelet adhesion and hemolysis ratio compared to expanded polytetrafluoroethylene graft while comparable blood clotting profiles were observed for both electrospun scaffold and expanded polytetrafluoroethylene graft. However, inflammatory response to nanofibrous surface of the scaffold was reduced compared to expanded polytetrafluoroethylene graft. The electrospun scaffold also presented a significantly more supportive substrate for endothelialization than the expanded polytetrafluoroethylene graft. The results described herein suggested that the three-layered scaffold has superior biological properties compared to an expanded polytetrafluoroethylene graft for vascular tissue engineering., (© The Author(s) 2016.)

Although edible collagen casing has been commercially used in meat industry, the safety and effectiveness of collagen cross-linking with minimally invasive treatments are still big concerns for manufacturers. In this study, ultraviolet irradiation (UV) and dehydrothermal treatment (DHT) were used to improve the properties of casing. UV, DHT, and their combination (UV+DHT) significantly increased tensile strength and decreased elongation at break of casing, in which DHT showed the best performance. Swelling of casing was also partially inhibited by the treatments. Furthermore, UV and DHT slightly improved thermal stability of the casings. In addition, X-ray diffraction patterns showed the treatments caused different extents of denaturation of collagen. No obvious effects in thickness and light transparency except for surface roughness were observed in the treated casings. The physical treatments could potentially be used as safe and effective alternatives to chemical cross-linking for the production of collage casing., (Copyright © 2015 Elsevier B.V. All rights reserved.)