Correction: An environmentally benign approach to achieving vectorial alignment and high microporosity in bacterial cellulose/chitosan scaffolds (original) (raw)

Engineering microporosity in bacterial cellulose scaffolds

Journal of Tissue Engineering and Regenerative Medicine, 2008

The scaffold is an essential component in tissue engineering. A novel method to prepare threedimensional (3D) nanofibril network scaffolds with controlled microporosity has been developed. By placing paraffin wax and starch particles of various sizes in a growing culture of Acetobacter xylinum, bacterial cellulose scaffolds of different morphologies and interconnectivity were prepared. Paraffin particles were incorporated throughout the scaffold, while starch particles were found only in the outermost area of the resulting scaffold. The porogens were successfully removed after culture with bacteria and no residues were detected with electron spectroscopy for chemical analysis (ESCA) or Fourier transform infra-red spectroscopy (FT-IR). Resulting scaffolds were seeded with smooth muscle cells (SMCs) and investigated using histology and organ bath techniques. SMC were selected as the cell type since the main purpose of the resulting scaffolds is for tissue engineered blood vessels. SMCs attached to and proliferated on and partly into the scaffolds.

Biosynthesis and characterization of bacteria cellulose–chitosan film

Carbohydrate Polymers, 2008

Many advances in nanomaterials synthesis have been recorded during the last 30 years. Bacterial cellulose (BC) produced by bacteria belonging to the genera Acetobacter, Rhizobium, Agrobacterium, and Sarcina is acquiring major importance as one of many eco-friendly materials with great potential in the biomedical field. The shape of BC bulk is sensitive to the container shape and incubation conditions such as agitation, carbon source, rate of oxygenation, electromagnetic radiation, temperature, and pH. The challenge is to control the dimension and the final shape of biosynthesized cellulose, by the optimization of culture conditions. The production of 3D structures based on BC is important for many industrial and biomedical applications such as paper and textile industries, biological implants, burn dressing material, and scaffolds for tissue regeneration. In our work, wild strains of Acetobacter spp. were isolated from homemade vinegar then purified and used for cellulose production. Four media of different initial viscosity were used. Cultures were performed under static conditions at 29 o C, in darkness. The dimensions and texture of obtained bacterial cellulose nanofibers were studied using scanning electron microscopy (SEM). X-ray diffraction (XRD) showed that the biosynthesized material has a cellulose I crystalline phase characterized by three crystal planes. fourrier transform infrared spectroscopy (FTIR) data confirmed the chemical nature of the fibers. Thermo-gravimetric analysis (TGA) showed that BC preserves a relatively superior nondegradable fraction compared to microcrystalline cellulose.

Preparation and characterization of a Bacterial cellulose/Chitosan composite for potential biomedical application

Journal of Polymer Research, 2011

Bacterial cellulose (BC)/Chitosan (Ch) composite has been successfully prepared by immersing wet BC pellicle in Ch solution followed by freeze-drying process. The morphology of BC/Ch composite was examined by scanning electron microscope (SEM) and compared with pristine BC. SEM images show that Ch molecules can penetrate into BC forming three-dimensional multilayered scaffold. The scaffold has very well interconnected porous network structure and large aspect surface. The composite was also characterized by Fourier transform infrared spectrum, X-ray diffraction, thermogravimetric analysis and tensile test. By incorporation of Ch into BC, crystallinity tends to decrease from 82% to 61%, and the thermal stability increases from 263°C to 296°C. At the same time, the mechanical properties of BC/Ch composite are maintained at certain levels between BC and Ch. The biocompatibility of composite was preliminarily evaluated by cell adhesion studies. The cells incubated with BC/Ch scaffolds for 48 h were capable of forming cell adhesion and proliferation. It showed much better biocompatibility than pure BC. Since the prepared BC/Ch scaffolds are bioactive and suitable for cell adhesion, these scaffolds can be used for wound dressing or tissue-engineering scaffolds.

Bacterial Cellulose—A Remarkable Polymer as a Source for Biomaterials Tailoring

Materials, 2022

Nowadays, the development of new eco-friendly and biocompatible materials using ‘green’ technologies represents a significant challenge for the biomedical and pharmaceutical fields to reduce the destructive actions of scientific research on the human body and the environment. Thus, bacterial cellulose (BC) has a central place among these novel tailored biomaterials. BC is a non-pathogenic bacteria-produced polysaccharide with a 3D nanofibrous structure, chemically identical to plant cellulose, but exhibiting greater purity and crystallinity. Bacterial cellulose possesses excellent physicochemical and mechanical properties, adequate capacity to absorb a large quantity of water, non-toxicity, chemical inertness, biocompatibility, biodegradability, proper capacity to form films and to stabilize emulsions, high porosity, and a large surface area. Due to its suitable characteristics, this ecological material can combine with multiple polymers and diverse bioactive agents to develop new m...

Exploring the evolution of bacterial cellulose precursors and their potential use as cellulose-based building blocks

Scientific reports, 2024

Natural polymers have found increased use in a wider range of applications due to their less harmful effects. Notably, bacterial cellulose has gained significant consideration due to its exceptional physical and chemical properties and its substantial biocompatibility, which makes it an attractive candidate for several biomedical applications. This study attempts to thoroughly unravel the microstructure of bacterial cellulose precursors, known as bioflocculants, which to date have been poorly characterised, by employing both electron and optical microscopy techniques. Here, starting from bioflocculants from Symbiotic Culture of Bacteria and Yeast (SCOBY), we proved that their microstructural features, such as porosity percentage, cellulose assembly degree, fibres' density and fraction, change in a spatio-temporal manner during their rising toward the liquid-air interface. Furthermore, our research identified a correlation between electron and optical microscopy parameters, enabling the assessment of bioflocculants' microstructure without necessitating offline sample preparation procedures. The ultimate goal was to determine their potential suitability as a novel cellulose-based building block material with tuneable structural properties. Our investigations substantiate the capability of SCOBY bioflocculants, characterized by distinct microstructures, to successfully assemble within a microfluidic device, thereby generating a cellulose sheet endowed with specific and purposefully designed structural features.

Recent advances in bacterial cellulose

Cellulose, 2014

Bacterial cellulose (BC) produced by some microorganisms has been widely accepted as a multifunctional nano-biomaterial. It is composed of linear glucan molecules attached with hydrogen bonds, which appears similar to plant cellulose. However, when compared with other conventional natural or synthesized counterparts, BC performs better in areas such as biomedicine, functional devices, water treatment, nanofillers, etc. for its distinct superior chemical purity, crystallinity, biocompatibility, and ultrafine network architecture. When BC is incorporated in a material or used as a scaffold, novel features result that are related to BC's intrinsic characteristics mentioned above. This review mainly summarizes the recent developments of the functional products fabricated with BC. Besides, the controllable cultivation conditions should also be discussed for expecting to make a breakthrough in its productivity. We highlight the literatures mainly in last 5 years, exerting ourselves to provide the state-ofthe-art opinions in areas wherever are focused on for BC researching.

Modification of bacterial cellulose to scaffold-like structures applied in process engineering

2016

Scaffolds are three-dimensional structures which provides necessary support for different cells’ vital functions. Although they are widely produced from different materials, most of them are not biodegradable. Bacterial bionanocellulose (BNC) has this property and additionally, has similar features to natural, extracellular matrixes. Unfortunately, natural channels which are in BNC’s structure have not sufficient diameter to colonize them with, for example, mammalian cells. Some experiments for pores enlargement in cellulose structure have been conducted. Multiple frosting and defrosting of properly prepared BNC’s samples has produced some positive results. Application the mixture of sterile vegetable oil and ethanol at the cultured layers of bionanocellulose gave expected results – diameter of the channels and chambers is enough to colonize them with viable cells. The results of described experiments give hope that bacterial bionanocellulose, because of its transformation’s simplic...

Bacterial cellulose: fabrication, characterization and biocompatibility studies

2014

En marzo de 2011, aplique a una beca del CSC (Consejo de Becas de China), en cooperacion con la Universitat Autonoma de Barcelona (UAB). Despues de medio ano, consegui la beca y comence mi tesis doctoral bajo la supervision de la Dra. Anna Roig y la Dra. Anna Laromaine. Mi proyecto asignada era en celulosa bacteriana: su sintesis, caracterizacion y estudios de biocompatibilidad. La celulosa bacteriana es un polisacarido de fuentes renovables, y puede ser producida por algunos tipos de bacterias en la naturaleza. Presenta propiedades quimicas y fisicas notables, incluyendo una alta pureza quimica y cristalinidad, una red de nanofibras, porosa, alta capacidad de absorcion de agua y resistencia mecanica. La celulosa bacteriana se utiliza para una amplia variedad de aplicaciones comerciales. Por otra parte, la celulosa bacteriana es biocompatible con afinidad biologica y biodegradabilidad, que suscita la atencion de investigadores en el area de la biomedicina. El primer objetivo de mi t...

Progress in bacterial cellulose matrices for biotechnological applications

Bacterial cellulose (BC) is an extracellular polymer produced by many microorganisms. The Komagataeibacter genus is the best producer using semi-synthetic media and agricultural wastes. The main advantages of BC are the nanoporous structure, high water content and free hydroxyl groups. Modification of BC can be made by two strategies: in-situ, during the BC production, and ex-situ after BC purification. In bioprocesses, multilayer BC nanocomposites can contain biocatalysts designed to be suitable for outside to inside cell activities. These nanocomposites biocatalysts can (i) increase productivity in bioreactors and bioprocessing, (ii) provide cell activities does not possess without DNA cloning and (iii) provide novel nano-carriers for cell inside activity and bioprocessing. In nanomedicine, BC matrices containing therapeutic molecules can be used for pathologies like skin burns, and implantable therapeutic devices. In nanoelectronics, semiconductors BC-based using salts and synthetic polymers brings novel films showing excellent optical and photochemical properties.