China
Africa
Explore chapters and articles related to this topic
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
Biomimetics means, to look towards nature for ideas that may be adapted and adopted for solving problems or create new solutions. One of the natural processes to which biomimetic takes inspiration is without any doubt biomineralization, a very peculiar, natural, as well as transversal phenomenon, of interest to many different living organisms from diatoms to humans, passed by plants. It refers to the processes by which organisms form minerals starting from simple compounds and are defined biogenic minerals or biominerals. It is, therefore, by definition, a true multidisciplinary field that spans from both the inorganic and the organic world. But, why should living organisms form minerals? The main functions of mineralized tissues can many, among them protection, motion, cutting, grinding, optical, magnetic and gravity sensing as well as storage (Talham 2002; Weiner 2003).
Sponge Enzyme's Role in Biomineralization and Human Applications
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Moin Merchant, Maushmi S. Kumar
Biomineralization is the process by which organic molecules combine with inorganic molecules by a living organism (Estroff, 2008). As a result of the living organism’s metabolism, biominerals can be deposited within the organism as well as in its immediate surroundings or environment. The organisms’ communication to one another and the formation of skeletal minerals, as well as their forms and functions, are affected by natural selection over geologic time. They are evolving in a controlled manner, resulting in monophyletic groups also known as clades. Biomineralization helps maintain the hardness and stiffness in the body form and shape of multicellular creatures (Weiner and Wagner, 1998). These activities take place both extracellularly and intracellularly, in the skeletons of animals and plants as well as in the creation of Fe3O4-based nanocrystals in magnetotactic bacteria, respectively. Biomineral production is governed by the same mechanisms that govern the formation of other biological macromolecules in living organisms (Faivre and Schüler, 2008). It is carried out by enzymes and operates at ambient and physiological conditions with nonsaturating concentrations. The morphogenetic biomineralization processes are genetically controlled and integrated with the anabolic and catabolic metabolic pathways (Uriz, 2006). The genetically controlled biomineralization processes differ from the physiologically induced biomineralization reactions. Bio-seeds nucleate the subsequent formation of mineral deposits of various forms and sizes during the biological induction of the mineralization process in deepsea nodules or crusts. The organisms have good control over the nucleation process and the shape and size of the mineral deposits in genetically driven mineralization processes (Wang and Müller, 2009). As the functional groups of organic molecules can influence the deposition of ions, salts, and inorganic monomeric and polymeric units, they can greatly enhance biomineralization process with an interplay between organic chemical macromolecules and inorganic components (Westbroek, 1983; Lowenstam and Weiner, 1983). These nuances are fundamental for the formation of the skeleton, even for the stabilization of bones in vertebrates. The organic reactions in complex biological systems were elucidated only after the discovery of enzymes, which was accelerated by the decoding of the genetic code and subsequent application of recombinant techniques (Weiner and Wagner, 1998). The production and deposition of silica and calcium carbonate (CaCO3) are driven enzymatically in sponges, as supported by the evolutionary studies (Müller et al., 2004).
Proteomes of the past: the pursuit of proteins in paleontology
Published in Expert Review of Proteomics, 2019
These common mineralization modes of soft animal part preservation do preserve gross anatomy [78,79], and in some cases microanatomy [80], but none preserve as much biological or taphonomic information as do primary protein sequences, isotope analyses of primary biominerals, or original organically preserved residual or whole tissues. In addition to suggesting how future studies might apply new technologies to test diagenetic scenarios, an even more significant task is to test whether or not new applications of established technologies or altogether new technologies can increase protein detection sensitivity and efficiency enough to help resolve current controversy on bone collagen (and by extension proteins in general) longevity.
Subsea tunnel reinforced sprayed concrete subjected to deterioration harbours distinct microbial communities
Published in Biofouling, 2018
Sabina Karačić, Britt-Marie Wilén, Carolina Suarez, Per Hagelia, Frank Persson
A novel case of biodeterioration of fibre reinforced sprayed concrete used for rock support has been detected in some Norwegian subsea tunnels (Hagelia 2007). Previous research, mainly focusing on the Oslofjord subsea tunnel, has shown that degradation of the cement paste matrix was due to a combined biotic and abiotic attack. Biofilms of iron-rich dark rusty to orange slime and manganese-rich dark material, associated with saline leakages on the rough and tortuous sprayed concrete surfaces, had caused variably deep disintegration of the calcium silicate hydrate (C-S-H). This effect was at least partly due to acidification (pH 5.5–6.5) of saline tunnel waters (pH 7.5–8) caused by chemical reactions within the biofilms. A multiproxy study, involving concrete petrography, scanning electron microscopy (SEM), microchemical analysis, X-ray diffraction, water chemical analysis and stable carbon and sulphur isotopes, demonstrated that reactions within the biofilm were influenced by biomineral formation and redox reactions, being sensitive to growth of biota. The biofilms interacted with the iron, manganese, sulphur, carbon and nitrogen cycles. Carbonates such as calcite, aragonite and magnesite occurred in degraded concrete underneath biofilm in the presence of biominerals (Mn-oxides buserite and todorokite and ferrihydrite). Reduction of Mn, Fe and S took place in thick biofilms involving temporary formation of sulphide. The evidence suggests that acidification within the biofilm was caused by oxidation of Fe(II) and Mn(II), sulphuric acid formed by reoxidation of sulphides, redox reactions between Fe and Mn compounds and organic acids. Microorganisms visible under SEM resembled Gallionella or Mariprofundus and Leptrohrix discophora, associated with manganese oxides. The abiotic attack mainly affected the concrete adjacent to the rock mass, being characterised by calcium leaching, breakdown of portlandite, magnesium attack and thaumasite sulphate attack and transformations of the cement paste matrix in response to ion-rich water. Further details may be found in Hagelia (2011a).
Microneedles for transdermal drug delivery using clay-based composites
Published in Expert Opinion on Drug Delivery, 2022
Farzaneh Sabbagh, Beom Soo Kim
In the field of microneedle manufacturing, polymers have received increasing attention from the outset due to their ease of manufacture, tunable physicochemical properties, cost effectiveness, improved biocompatibility, and absence of sharp waste. Like their metal and silicone counterparts, polymer microneedles were first used, after topical application of lotion, to open skin microchannels to enhance penetration of active ingredients [26]. After that, research was conducted on the production of microneedles using biodegradable polymers that contain therapeutic agents in a matrix and that control dissolution or degradation when inserted into the skin. Depending on the dissolution rate of the polymer, these microneedles are classified as soluble or degradable [27,28]. Soluble patches are usually made of highly soluble polymers that dissolve and release drugs quickly. Soluble patches contain various water-soluble polymers such as carboxymethyl cellulose [29], hyaluronic acid [30], polyvinyl alcohol (PVA) [26], polyvinylpyrrolidone (PVP) [31], maltose [32], and chitosan [33]. Degradable microneedles are generally considered to have a slow dissolution rate and a long release profile. They have traditionally been fabricated using biocompatible polymers with high molecular weight and high degree of crosslinking, such as polylactide [34]. Drugs are constantly released by passive decomposition or diffusion of the polymer structure. Recently, sustained release has been achieved using materials that incorporate secondary encapsulating elements (biominerals, polymeric nanoparticles) into a dissolution matrix. Much effort has been devoted to creating (bio)responsive polymer microneedles [35]. These microneedle patches can release implanted drugs in response to stimulation induction. These stimuli may come from physiological events or external sources [36,37]. Externally applied thermal or light indicators have been shown to cause release of therapeutic agents loaded into polymer matrixes. This improved method involves physiological signals such as alterations in levels of reactive oxygen species [38], glucose, or pH, causing lysis of the microneedle array, releasing the therapeutic agent [39].