Search

A novel design of bioreactor G-BNC, in combination with two previously reported designs of bioreactor were used to fabricate three small caliber bacterial nanocellulose (BNC) conduits (G-BNC, S-BNC and D-BNC). They were compared systematically with a clinically-used ePTFE graft. S-BNC possessed a laminated structure, the lowest BNC content, roughest luminal surface and weakest mechanical properties, and so might not be sufficiently strong for use as an artificial blood vessel alone. The D-BNC conduit possessed an unstratified structure with a fiber network that was more dense and the greatest BNC content, providing the strongest mechanical properties. G-BNC possessed a looser network with the smoothest luminal surface and greater hemocompatibility. Following comprehensive evaluation of mechanical properties and performance, we judge that D-BNC and G-BNC should possess greater potential in application as small caliber vascular grafts, however the patency of the three BNC conduits need be further verified in animal studies in vivo., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In order to improve property of bacterial nano-cellulose (BNC) to achieve the requirements of clinical application as small caliber vascular grafts, chitosan (CH) was deposited into the fibril network of the BNC tubes fabricated in unique Double-Silicone-Tube bioreactors. Heparin (Hep) was then chemically grafted into the BNC-based tubes using EDC/NHS crosslinking to improve performance of anticoagulation and endothelialization. Physicochemical and mechanical property, blood compatibility, and cytocompatibility were compared before and after compositing. The results indicated that strength at break was increased but burst pressure decreased slightly after compositing. Performance of the BNC tubes was improved remarkably after introducing chitosan and heparin. The EDC/NHS crosslinking catalyzed both amide bonds and ester bonds formation in the BNC/CH-Hep composites. Three-dimensional surface structure and roughness were firstly obtained and discussed in relation to the hemocompatibility of BNC-based tubes. This work demonstrates the heparinized BNC-based tubes have great potential in application as small-diameter vascular prosthesis., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

BACKGROUND Bacterial nanocellulose ( BNC) has prospects for use in applications of artificial blood vessels, esophagus and urethra. Several bioreactors have been utilized for synthesis of BNC tubes, however, little is known about differences in biosynthesis processes and tube properties. The current work for the first time compared two types of bioreactors, double-silicone-tube (D- BNC) and single-silicone-tube (S- BNC) bioreactors, to evaluate differences in preparation and properties of BNC tubes using fructose or glucose of 50 g L−1 and 100 g L−1, respectively. RESULTS The two bioreactors showed different biosynthesis processes of BNC tube production. The D- BNC bioreactor provided higher yields and better mechanical performance of tubes because of the greater oxygen supply. Higher fructose concentration resulted in increased production of D- BNC, but sugar types and concentrations had little effect on S- BNC yields. Fructose granted stronger mechanical properties, but lower water permeability. Both types of tubes prepared with 100 g L−1 fructose were composed of porous nano-fibrillar networks but showed different cross-sectional morphologies and fiber distributions. CONCLUSION This study revealed the biosynthesis processes of BNC tubes in two bioreactors and their correlation with properties. The results suggest how to regulate BNC tubes with particular structures and properties for biomedical prostheses including artificial blood vessels. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]