scholarly journals Modulating the Physicochemical Properties of Chitin and Chitosan as a Method of Obtaining New Biological Properties of Biodegradable Materials

2021 ◽  
Author(s):  
Ilona Latańska ◽  
Piotr Rosiak ◽  
Paulina Paul ◽  
Witold Sujka ◽  
Beata Kolesińska

Physical and chemical modifications of chitin and chitosan allow for obtaining new functional properties of the natural polymers. This is a particularly valuable feature for the design and manufacture of new materials for medical applications. Due to their wide and varied biological activity, chitin and chitosan materials are increasingly used as dressing materials with antibacterial and hemostatic properties and as materials accelerating the regeneration of damaged tissues because of stimulation of granulation tissue formation, re-epithelialization and reduction of the formation of scar tissue. In addition, chitosan derivatives have antifungal, antiviral, anticancer activity. The increasing use of chitin and chitosan also has a positive impact on the environment, as it is obtained as a result of chitin deacetylation, usually isolated from shellfish shells. The main source of chitin is waste coating of crustaceans. The annual natural reproducibility of chitin by biosynthesis is estimated at 2–3 billion tons. Our interest in the use of biodegradable biopolymers derived from chitin concerns the design, synthesis in laboratory scale, testing new material properties and the final implementation of new developments for industrial practice of new dressing materials useful in the treatment of bleeding wounds (haemostatic properties) as well as in the regeneration of wounds and ulcers of various etiologies. Examples of chitin-based dressing materials introduced by Tricomed SA are Medisorb R Ag, Medisorb R Membrane, Medisorb R Powder and Tromboguard®.

2018 ◽  
Vol 7 (4.3) ◽  
pp. 320
Author(s):  
L. A. Bezdeneznych ◽  
O. V. Kharlamova ◽  
V. M. Shmandiy

To minimize the impact of industrial enterprises on water objects, a wide variety of adsorbents (based on activated carbon, natural materials, nanomaterials, vegetable waste of agro-industrial complex, etc.) is used. Recently, chitin and chitosan have attracted the attention of scientists due to a number of unique physico-chemical and biological properties (adsorption, antioxidant, radioprotective, immunomodulating, lamina-forming). We have improved the method of obtaining powdered chitosan and established the basic physical and chemical parameters (bulk density, humidity). The method of obtaining chitosan granules and composite materials based on chitosan and modified sunflower husks (MSH) has been further developed by the "drip method". The adsorption properties of powder chitosan, chitosan granules and MSH were studied. It is set that a granular adsorbent has a high adsorbtivity in comparing to the original chitosan. Efficiency of wastewater treatment with the use of chitosan granules and MSH is equally high (up to 98%). The optimum amount of adsorbent for effective cleaning of contaminated water is 1% of its volume. The use of the results of the conducted research allows us to obtain an effective adsorbent for the treatment of industrial waste water. 


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Kieran Joyce ◽  
Georgina Targa Fabra ◽  
Yagmur Bozkurt ◽  
Abhay Pandit

AbstractBiomaterials have had an increasingly important role in recent decades, in biomedical device design and the development of tissue engineering solutions for cell delivery, drug delivery, device integration, tissue replacement, and more. There is an increasing trend in tissue engineering to use natural substrates, such as macromolecules native to plants and animals to improve the biocompatibility and biodegradability of delivered materials. At the same time, these materials have favourable mechanical properties and often considered to be biologically inert. More importantly, these macromolecules possess innate functions and properties due to their unique chemical composition and structure, which increase their bioactivity and therapeutic potential in a wide range of applications. While much focus has been on integrating these materials into these devices via a spectrum of cross-linking mechanisms, little attention is drawn to residual bioactivity that is often hampered during isolation, purification, and production processes. Herein, we discuss methods of initial material characterisation to determine innate bioactivity, means of material processing including cross-linking, decellularisation, and purification techniques and finally, a biological assessment of retained bioactivity of a final product. This review aims to address considerations for biomaterials design from natural polymers, through the optimisation and preservation of bioactive components that maximise the inherent bioactive potency of the substrate to promote tissue regeneration.


2021 ◽  
pp. 0958305X2198988
Author(s):  
Nur Syakirah Rabiha Rosman ◽  
Noor Aniza Harun ◽  
Izwandy Idris ◽  
Wan Iryani Wan Ismail

The emergence of technology to produce nanoparticles (1 nm – 100 nm in size) has drawn significant researchers’ interests. Nanoparticles can boost the antimicrobial, catalytic, optical, and electrical conductivity properties, which cannot be achieved by their corresponding bulk. Among other noble metal nanoparticles, silver nanoparticles (AgNPs) have attained a special emphasis in the industry due to their superior physical, chemical, and biological properties, closely linked to their shapes, sizes, and morphologies. Proper knowledge of these NPs is essential to maximise the potential of biosynthesised AgNPs in various applications while mitigating risks to humans and the environment. This paper aims to critically review the global consumption of AgNPs and compare the AgNPs synthesis between conventional methods (physical and chemical) and current trend method (biological). Related work, advantages, and drawbacks are also highlighted. Pertinently, this review extensively discusses the current application of AgNPs in various fields. Lastly, the challenges and prospects of biosynthesised AgNPs, including application safety, oxidation, and stability, commercialisation, and sustainability of resources towards a green environment, were discussed.


2021 ◽  
Vol 22 (9) ◽  
pp. 4308
Author(s):  
Chayanaphat Chokradjaroen ◽  
Jiangqi Niu ◽  
Gasidit Panomsuwan ◽  
Nagahiro Saito

Sustainability and environmental concerns have persuaded researchers to explore renewable materials, such as nature-derived polysaccharides, and add value by changing chemical structures with the aim to possess specific properties, like biological properties. Meanwhile, finding methods and strategies that can lower hazardous chemicals, simplify production steps, reduce time consumption, and acquire high-purified products is an important task that requires attention. To break through these issues, electrical discharging in aqueous solutions at atmospheric pressure and room temperature, referred to as the “solution plasma process”, has been introduced as a novel process for modification of nature-derived polysaccharides like chitin and chitosan. This review reveals insight into the electrical discharge in aqueous solutions and scientific progress on their application in a modification of chitin and chitosan, including degradation and deacetylation. The influencing parameters in the plasma process are intensively explained in order to provide a guideline for the modification of not only chitin and chitosan but also other nature-derived polysaccharides, aiming to address economic aspects and environmental concerns.


2021 ◽  
Vol 14 (5) ◽  
pp. 422
Author(s):  
Kseniya Kovaleva ◽  
Olga Yarovaya ◽  
Konstantin Ponomarev ◽  
Sergey Cheresiz ◽  
Amirhossein Azimirad ◽  
...  

In this paper, a series of novel abietyl and dehydroabietyl ureas, thioureas, amides, and thioamides bearing adamantane moieties were designed, synthesized, and evaluated for their inhibitory activities against tyrosil-DNA-phosphodiesterase 1 (TDP1). The synthesized compounds were able to inhibit TDP1 at micromolar concentrations (0.19–2.3 µM) and demonstrated low cytotoxicity in the T98G glioma cell line. The effect of the terpene fragment, the linker structure, and the adamantane residue on the biological properties of the new compounds was investigated. Based on molecular docking results, we suppose that adamantane derivatives of resin acids bind to the TDP1 covalent intermediate, forming a hydrogen bond with Ser463 and hydrophobic contacts with the Phe259 and Trp590 residues and the oligonucleotide fragment of the substrate.


Author(s):  
Ishowriya Yumnam

In this review article the usage of waste sewage sludge and the biomass ash for improving the engineering and non-engineering properties’ of both concrete and soil are discussed in detail. Numerous past research works were studied in detail so as to predict the behavior of biomass ash and waste sewage sludge when used for the stabilization process of soil and concrete. Past studies related to the usage of stabilized sewage sludge and biomass ash were studied in a detailed manner and depending upon the past studies several conclusions has been drawn which are discussed further. Several studies related to the usage of the waste sewage sludge for improving soil physical, chemical and biological properties showed that the usage of waste sewage sludge improve the physical properties, chemical properties, macro-nutriential properties and micro-nutriential properties up to a great extent. Depending upon the results of the past studies it can be concluded that the usage of sewage sludge has positive impact over all the properties of soil and this waste should be utilized in improving the properties of soil rather than dumping. Numerous studies related to the usage of the biomass ash showed that biomass ash has positive impact over both soil as well as concrete. Studies related to the usage of the biomass ash in soil showed that there was a positive response of the stabilized soil after its stabilization with the biomass ash. Studies related to the usage of the biomass ash in concrete showed that the biomass ash can be used up to 10 percent replacement of the ordinary Portland cement so as to attain maximum strength results from it.


Messenger ◽  
2014 ◽  
Vol 3 (1) ◽  
pp. 35-51 ◽  
Author(s):  
Takayoshi Tsuzuki ◽  
Satoshi Takano ◽  
Natsumi Sakaguchi ◽  
Takashi Kudoh ◽  
Takashi Murayama ◽  
...  

2014 ◽  
Vol 70 (a1) ◽  
pp. C1223-C1223
Author(s):  
Jason Benedict ◽  
Ian Walton ◽  
Dan Patel ◽  
Jordan Cox

Metal-organic Frameworks (MOFs) remain an extremely active area of research given the wide variety of potential applications and the enormous diversity of structures that can be created from their constituent building blocks. While MOFs are typically employed as passive materials, next-generation materials will exhibit structural and/or electronic changes in response to applied external stimuli including light, charge, and pH. Herein we present recent results in which advanced photochromic diarylethenes are combined with MOFs through covalent and non-covalent methods to create photo-responsive permanently porous crystalline materials. This presentation will describe the design, synthesis, and characterization of next-generation photo-switchable diarylethene based ligands which are subsequently used to photo-responsive MOFs. These UBMOF crystals are, by design, isostructural with previously reported non-photoresponsive frameworks which enables a systematic comparison of their physical and chemical properties. While the photoswitching of the isolated ligand in solution is fully reversible, the cycloreversion reaction is suppressed in the UBMOF single crystalline phase. Spectroscopic evidence for thermally induced cycloreversion will be presented, as well as a detailed analysis addressing the limits of X-ray diffraction techniques applied to these systems.


Author(s):  
Ramakoteswara Rao N ◽  
Kranthi kiran Reddy E ◽  
Leena Gahane ◽  
SV Ranganayakulu

Nano technology is the multi disciplinary science and technology, which has emerged as new science exploiting specific phenomena and direct manipulation of materials on nanoscale. Nanotechnology deals with the physical, chemical, and biological properties of structures and their parts at nanoscale dimensions. It's established on the concept by creating functional structures by controlling corpuscles and molecules on a one-by-one basis by different physical and chemical synthesis methods. Developments in materials science and, nano biotechnology is especially forestalled to provide elevates in dental sciences and initiations in oral health-related diagnostic and therapeutical methods. Keywords: Nano Science, dentistry, Nanocomposite, Nanorobots, Nanomaterials.


2014 ◽  
Vol 70 (a1) ◽  
pp. C141-C141
Author(s):  
Ozen Ozgen ◽  
Engin Kendi ◽  
Semra Koyunoglu ◽  
Akgul Yesilada ◽  
Hwo-Shuenn Sheu

A significant part of medicine is based on the discovery and development of drugs. It is very important to know the crystal structure of pharmaceutical compounds for fundamental understanding of structure, physical and chemical properties. Many of these materials are available only as powders. So any structural information must be obtained from powder diffraction. I am going to present following the stages while solving the structure of C23H19N4OBr, 2-[3-phenyl-4(m-bromophenyl)-2-pyrazolin-1-yl]-3-methyl-4(3H)-quinazolinone, from 2-pyrazolines derivatives. The compounds are known to display various biological properties such as fungicidal insecticidal, anti bacterial, anti viral activities, pharmacological properties such as antiinflammatory agents and have industral properties(1). The powder diffraction data was collected with Debye Scherrer camera at the BL01C2 beamline at room temperature in National Synchrotron Radiation Research Center(NSRRC), Taiwan. X-ray of wavelength was 1.0333Å. This compound crystallizes in orthorhombic system space group P bca, Z=8, unit cell parameters of a=25.83(1)Å, b=15.55(5)Å, c=10.63(3)Å, and V=4266.0(10)Å3. Reliability factors were reached Rwp=0.075, Rp=0.053, RB=0.086 ve S=1.31 after Rietveld refinement.


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