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Biomimetic Approaches for the Design and Development of Multifunctional Bioresorbable Layered Scaffolds for Dental Regeneration
Published in Vincenzo Guarino, Marco Antonio Alvarez-Pérez, Current Advances in Oral and Craniofacial Tissue Engineering, 2020
Campodoni Elisabetta, Dozio Samuele Maria, Mulazzi Manuela, Montanari Margherita, Montesi Monica, Panseri Silvia, Sprio Simone, Tampieri Anna, Sandri Monica
Besides collagen, many other polymers have been exploited as possible matrices for biomineralization; among them gelatin, chitosan, alginate and nano-cellulose (Campodoni et al. 2016; Panseri et al. 2016) Thanks to their chemical structure, all of the above-mentioned biopolymers are able to undertake the biomineralization process with interesting different final results in terms of mechanical and physical properties, biological activity and biodegradation kinetic that can be exploited to achieve disparate regenerative goals.
Injectable Scaffolds for Bone Tissue Repair and Augmentation
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Subrata Bandhu Ghosh, Kapender Phogat, Sanchita Bandyopadhyay-Ghosh
Bacterial nanocellulose (BC) has also been employed as a template for the ordered formation of calcium-deficient hydroxyapatite (CdHAP) (Chang and Zhang 2011). The BC-CdHAP nanocomposites were produced by introducing the mineral phase into the bacteria culture media. The results indicated formation of CdHAP spherical clusters, composed of nanosized crystallites, which could be attributed to the similarity of natural bone apatite with CdHAP precursor (Chang and Zhang 2011). The injectable nanocomposites could exploit the bioactivity of CdHAP and biocompatibility of the BC hydrogel for potential orthopedic applications. It was reported that use of carboxymethyl cellulose (CMC) reduced the average diameter of cellulose fibers significantly (almost 50% lower) than that of unmodified fibers (Chang and Zhang 2011, Polo-Corrales et al. 2014). In another attempt, BC-HAp nanocomposite membranes were tested in noncritical bone defects in rat tibiae for upto16 weeks. In vivo tests showed absence of any inflammatory reaction after 1 week, while, all defects were found to be completely filled in by regenerated bone tissue (Ginebra and Montufar 2014). Phogat and Bandyopadhyay-Ghosh have reported development of nanocellulose mediated bio-nanocomposite injectable hydrogel as bone graft substitute (Phogat and Bandyopadhyay-Ghosh 2018). They incorporated ultrafine-flurocanasite glass ceramic particulates within wheat straw derived nanocellulose matrix and the resulting bio-nanocomposite hydrogel demonstarted tunable vicoelasticity, self-standing property, and injectability.
Recent advancements in cellulose-based biomaterials for management of infected wounds
Published in Expert Opinion on Drug Delivery, 2021
Munira Momin, Varsha Mishra, Sankalp Gharat, Abdelwahab Omri
Nanocellulose has a high elastic modulus stiffness, which is superior to the strong synthetic fibers like Kevlar fiber. In addition, tensile strength of the nanocellulose is better than even cast iron, and its strength-to-weight ratio is eight folds greater than stainless steel. Also, nanocellulose is transparent in nature. The numerous hydroxyl groups on the surface of nanocellulose make it easy to functionalize by surface modification [188,189]. Nanocellulose is widely used in numerous fields, such as formation of nanocomposite materials, packaging, adhesives, electroactive polymers, and biomedical applications like wound healing, tissue regeneration, and 3D bioprinting. Nanocellulose has been very recently explored for the formation of bioink as it allows many mechanical modifications and there is no interference in the cell bioactivity after printing [190].
Lung toxicity and gene expression changes in response to whole-body inhalation exposure to cellulose nanocrystal in rats
Published in Inhalation Toxicology, 2021
Pius Joseph, Christina M. Umbright, Jenny R. Roberts, Jared L. Cumpston, Marlene S. Orandle, Walter G. McKinney, Tina M. Sager
A reduction in size of materials facilitates the generation of nanomaterials (<100 nm at least in one dimension) with many unique and desirable physical and chemical properties. Nanocellulose can be generated from large sized cellulose fibers either by physical or chemical processing. Acid hydrolysis of cellulose results in the generation of cellulose nanocrystal (CNC) while mechanical processing, for example shearing of cellulose by homogenization, results in the generation of cellulose nanofibril (CNF) (Charreau et al. 2013). The whisker-shaped CNC is characterized by a high degree of crystallinity (∼54–88%) and high aspect ratio (Moon et al. 2011). The many desirable physical properties of CNC, viz. high tensile strength and rigidity, high aspect ratio and surface area, low density, liquid crystalline behavior, high water absorption capacity, thermal stability, and ability to be easily obtained by chemical modifications (Habibi et al. 2010; Rol et al. 2020) offer many valuable applications as composites (Lee et al. 2012), in electronic products (Hubbe et al. 2008), in biomedical engineering (Mathew et al. 2013), and in drug delivery (Seabra et al. 2018). Additionally, CNC is inexpensive, biodegradable, biocompatible, and sustainable.
Human hazard potential of nanocellulose: quantitative insights from the literature
Published in Nanotoxicology, 2020
Natasha Stoudmann, Mélanie Schmutz, Cordula Hirsch, Bernd Nowack, Claudia Som
This review also highlights that inhalation of nanocellulose may cause adverse effects to human health. However, the scarcity of studies means that these effects are not yet fully understood or conclusive. Furthermore, little is known about the biopersistence of NC. More research needs to be done to ensure that NC is not affected by the fiber paradigm. Low dose, long-term studies looking at pulmonary exposure are still needed to fill this gap. Only one in vivo study performed a whole animal inhalation test, with all others having used installation or pharyngeal aspiration as exposure route. Occupational exposure to airborne NC during raw materials processing and manufacturing phase likely pose the greatest risk, and appropriate measures should be taken to ensure safe working conditions. Although few in numbers, none of the studies looking at the toxicity of NC via dermal contact have shown any cause for concern. The scenarios relating to dermal exposure pathways therefore probably do not pose a great risk within the occupational setting. The interest NC is generating for wound dressing may however call for more in-depth studies looking at the long-term impacts of NC on skin and especially on open wounds. Furthermore, the sensitivity of certain tested immune cells calls attention to the need for further studies looking at inflammation. Particularly when considering the fiber paradigm, as inflammation, as a mechanism of immune defense (Jesus et al. 2019) plays a role in the formation of mesothelioma, this endpoint remains key to ensuring the safe production and use of NC.