-
1.
Surface Stability and Morphology of Calcium Phosphate Tuned by pH Values and Lactic Acid Additives: Theoretical and Experimental Study.
Chen, H, Lv, C, Guo, L, Ma, M, Li, X, Lan, Z, Huo, J, Dong, H, Zhu, X, Zhu, Q, et al
ACS applied materials & interfaces. 2022;(4):4836-4851
Abstract
The ubiquitous mineralization of calcium phosphate (CaP) facilitates biological organisms to produce hierarchically structured minerals. The coordination number and strength of Ca2+ ions with phosphate species, oxygen-containing additives, and solvent molecules played a crucial role in tuning nucleation processes and the surface stability of CaP under the simulated body fluid (SBF) or aqueous solutions upon the addition of oligomeric lactic acid (LACn, n = 1, 8) and changing pH values. As revealed by ab initio molecular dynamics (AIMD), density functional theory (DFT), and molecular dynamics (MD) simulations as well as high-throughput experimentation (HTE), the binding of LAC molecules with Ca2+ ions and phosphate species could stabilize both the pre-nucleation clusters and brushite (DCPD, CaHPO4·2H2O) surface through intermolecular electrostatic and hydrogen bonding interactions. When the concentration of Ca2+ ions ([Ca2+]) is very low, the amount of the formed precipitation decreased with the addition of LAC based on UV-vis spectroscopic analysis due to the reduced chance for the LAC capped Ca2+ ions to coordinate with phosphates and the increased solubility in the acid solution. With the increasing [Ca2+] concentration, the kinetically stable DCPD precipitation was obtained with high Ca2+ coordination number and low surface energy. Morphologies of DCPD precipitation are in plate, needle, or rod, depending on the initial pH values that were tuned by adding NH3·H2O, HCl, or CH3COOH. The prepared samples at pH ≈ 7.4 with different Ca/P ratios exhibited negative zeta potential values, which were correlated with the surface electrostatic potential distributions and potential biological applications.
-
2.
An insight on egg white: From most common functional food to biomaterial application.
Dong, X, Zhang, YQ
Journal of biomedical materials research. Part B, Applied biomaterials. 2021;(7):1045-1058
Abstract
Natural egg white tis widely used as an ingredient in nutritional foods and for food processing. Due to its characteristic foaming, emulsification, adhesion, and gelation, and its heat setting, biocompatibility, and low cost, research into the application and development of egg white in biomaterials, especially medical biomaterials, have been receiving attention. The composition and characteristics of egg white protein, and the physical mixing and chemically cross-linking of egg white with other materials used to make degradable packaging films, bioceramics, bioplastics, biomimetic films, hydrogels, 3D scaffolds, bone regeneration, biopatterning, biosensors, and so forth, are reviewed in detail in this report. The novel egg white-based biomaterials in various forms and applications could be constructed mostly through physical treatments such as ultrasonic wave, ultraviolet, laser and other radiation or high-temperature calcination. Furthermore, the application and prospects for the use of egg white in biomaterials is also discussed.
-
3.
Autotolerant ceruloplasmin based biocathodes for implanted biological power sources.
Aleksejeva, O, Sokolov, AV, Marquez, I, Gustafsson, A, Bushnev, S, Eriksson, H, Ljunggren, L, Shleev, S
Bioelectrochemistry (Amsterdam, Netherlands). 2021;:107794
Abstract
High-performance autotolerant bioelectrodes should be ideally suited to design implantable bioelectronic devices. Because of its high redox potential and ability to reduce oxygen directly to water, human ceruloplasmin, HCp, the only blue multicopper oxidase present in human plasma, appears to be the ultimate biocatalyst for oxygen biosensors and also biocathodes in biological power sources. In comparison to fungal and plant blue multicopper oxidases, e.g. Myrothecium verrucaria bilirubin oxidase and Rhus vernicifera laccase, respectively, the inflammatory response to HCp in human blood is significantly reduced. Partial purification of HCp allowed to preserve the native conformation of the enzyme and its biocatalytic activity. Therefore, electrochemical studies were carried out with the partially purified enzyme immobilised on nanostructured graphite electrodes at physiological pH and temperature. Amperometric investigations revealed low reductive current densities, i.e. about 1.65 µA cm-2 in oxygenated electrolyte and in the absence of any mediator, demonstrating nevertheless direct electron transfer based O2 bioelectroreduction by HCp for the first time. The reductive current density obtained in the mediated system was about 12 µA cm-2. Even though the inflammatory response of HCp is diminished in human blood, inadequate bioelectrocatalytic performance hinders its use as a cathodic bioelement in a biofuel cell.
-
4.
Stimuli-responsive natural gums-based drug delivery systems for cancer treatment.
Soleimani, K, Derakhshankhah, H, Jaymand, M, Samadian, H
Carbohydrate polymers. 2021;:117422
Abstract
Chemotherapy as the main cancer treatment method has non-specific effects and various side-effects. Accordingly, significant attempts have been conducted to enhance its efficacy through design and development of "smart" drug delivery systems (DDSs). In this context, natural gums, as a nice gift by the nature, can be exploited as stimuli-responsive DDSs for cancer treatment in part due to their renewability, availability, low cost, bioactivity, biocompatibility, low immunogenicity, biodegradability, and acceptable stability in both in vitro and in vivo conditions. However, some shortcomings (e.g., poor mechanical properties and high hydration rate) restrict their biomedical application ranges that can be circumvented through modification process (e.g., grafting of stimuli-responsive polymers or small molecules) to obtain tailored biomaterials. This review article aimed to compile the stimuli-responsive DDSs based on natural gums. In addition, different types of stimuli, the fundamental features of natural gums, as well as their chemical modification approaches are also shortly highlighted.
-
5.
Excitation and ionisation cross-sections in condensed-phase biomaterials by electrons down to very low energy: application to liquid water and genetic building blocks.
de Vera, P, Abril, I, Garcia-Molina, R
Physical chemistry chemical physics : PCCP. 2021;(9):5079-5095
Abstract
Electronic excitations and ionisations produced by electron impact are key processes in the radiation-induced damage mechanisms in materials of biological relevance, underlying important medical and technological applications, including radiotherapy, radiation protection in manned space missions and nanodevice fabrication techniques. However, experimentally measuring all the necessary electronic interaction cross-sections for every relevant material is an arduous task, so it is necessary having predictive models, sufficiently accurate yet easily implementable. In this work we present a model, based on the dielectric formalism, to provide reliable ionisation and excitation cross-sections for electron-impact on complex biomolecular media, considering their condensed-phase nature. We account for the indistinguishability and exchange between the primary beam and excited electrons, for the molecular electronic structure effects in the electron binding, as well as for low-energy corrections to the first Born approximation. The resulting approach yields total ionisation cross-sections, energy distributions of secondary electrons, and total electronic excitation cross-sections for condensed-phase biomaterials, once the electronic excitation spectrum is known, either from experiments or from a predictive model. The results of this methodology are compared with the available experimental data in water and DNA/RNA molecular building blocks, showing a very good agreement and a great predictive power in a wide range of electron incident energies, from the large values characteristic of electron beams down to excitation threshold. The proposed model constitutes a very useful procedure for computing the electronic interaction cross-sections for arbitrary biological materials in a wide range of electron incident energies.
-
6.
Functional biomedical materials derived from proteins in the acquired salivary pellicle.
Zhang, F, Cheng, Z, Ding, C, Li, J
Journal of materials chemistry. B. 2021;(33):6507-6520
Abstract
In the oral environment, the acquired salivary pellicle (ASP) on the tooth surface comprises proteins, glycoproteins, carbohydrates, and lipids. The ASP can specifically and rapidly adsorb on the enamel surface to provide effective lubrication, protection, hydration, and remineralisation, as well as be recognised by various bacteria to form a microbial biofilm (plaque). The involved proteins, particularly various phosphoproteins such as statherins, histatins, and proline-rich proteins, are vital to their specific functions. This review first describes the relationship between the biological functions of these proteins and their structures. Subsequently, recent advances in functional biomedical materials derived from these proteins are reviewed in terms of dental/bone therapeutic materials, antibacterial materials, tissue engineering materials, and coatings for medical devices. Finally, perspectives and challenges regarding the rational design and biomedical applications of ASP-derived materials are discussed.
-
7.
Recent advances of thermal properties of sugar palm lignocellulosic fibre reinforced polymer composites.
Asyraf, MRM, Ishak, MR, Norrrahim, MNF, Nurazzi, NM, Shazleen, SS, Ilyas, RA, Rafidah, M, Razman, MR
International journal of biological macromolecules. 2021;(Pt B):1587-1599
Abstract
Biocomposites are materials that are easy to manufacture and environmentally friendly. Sugar palm fibre (SPF) is considered to be an emerging reinforcement candidate that could provide improved mechanical stiffness and strength to the biocomposites. Numerous studies have been recently conducted on sugar palm biocomposites to evaluate their physical, mechanical and thermal properties in various conditions. Sugar palm biocomposites are currently limited to the applications of traditional household products despite their good thermal stability as a prospective substitute candidate for synthetic fibres. Thus, thermal analysis methods such as TGA and DTG are functioned to determine the thermal properties of single fibre sugar palm composites (SPCs) in thermoset and thermoplastic matrix as well as hybrid SPCs. The biocomposites showed a remarkable change considering thermal stability by varying the individual fibre compositions and surface treatments and adding fillers and coupling agents. However, literature that summarises the thermal properties of sugar palm biocomposites is unavailable. Particularly, this comprehensive review paper aims to guide all composite engineers, designers, manufacturers and users on the selection of suitable biopolymers for sugar palm biocomposites for thermal applications, such as heat shields and engine components.
-
8.
Carbon nanohorns as nanocontainers for cisplatin: insight into their interaction with the plasma membranes of normal and breast cancer cells.
Almeida, ER, Dos Santos, HF, Capriles, PVSZ
Physical chemistry chemical physics : PCCP. 2021;(30):16376-16389
Abstract
Cisplatin (cddp)-based chemotherapy is one of the most effective therapeutic alternatives for breast cancer treatment, the most common form of cancer, despite the severe side effects related to the high toxicity and low selectivity of cddp. To circumvent these drawbacks, the encapsulation of cddp into oxidized carbon nanohorns (CNHoxs) has been shown as a promising formulation with biocompatibility and low toxicity. However, there is still a lack of studies regarding the behavior of this cddp@CNHox nanovector on the cell membranes. This study presents an in silico description of the interactions between cddp@CNHox and membrane models of cancer (C_memb) and normal (N_memb) cells referring to a typical human breast. The results revealed the interaction mechanism of the inclusion complex 3cddp@CNHox (three cddp molecules are included in the CNHox cavity) with these biomembranes, which is a multistep process including approach, landing, insertion, and penetration. The 3cddp@CNHox stability was monitored over time, and demonstrated the trapping of cddp molecules inside the CNHox cavity over all simulations. The van der Waals contribution played a primary role (∼74%) for the complex stability. Moreover, the binding free energy calculations indicated that the interaction of the 3cddp@CNHox complex with the C_memb model was slightly more favorable, on average, than with the N_memb model. Analysis of the hydrogen bonds (HBs) formed over simulations of 800 ns explains the selectivity for the C_memb model, since the total number of HBs established between the inclusion complex and the C_memb model was about three times greater than that with the N_memb model. By reinforcing the potentiality of oxidized CNHox as a nanovector of cddp, the results presented in this study may assist and drive new experimental studies with this nanomaterial, focusing on the development of less aggressive formulations for breast cancer treatment.
-
9.
Review of the Mechanism of Nanocarriers and Technological Developments in the Field of Nanoparticles for Applications in Cancer Theragnostics.
Shreyash, N, Sonker, M, Bajpai, S, Tiwary, SK
ACS applied bio materials. 2021;(3):2307-2334
Abstract
Cancer cannot be controlled by the usage of drugs alone, and thus, nanotechnology is an important technique that can provide the drug with an impetus to act more effectively. There is adequate availability of anticancer drugs that are classified as alkylating agents, hormones, or antimetabolites. Nanoparticle (NP) carriers increase the residence time of the drug, thereby enhancing the survival rate of the drug, which otherwise gets washed off owing to the small size of the drug particles by the excretory system. For example, for enhancing the circulation, a coating of nonfouling polymers like PEG and dextran is done. Famous drugs such as doxorubicin (DOX) are commonly encapsulated inside the nanocomposite. The various classes of nanoparticles are used to enhance drug delivery by aiding it to fight against the tumor. Targeted therapy aims to attack the cells with features common to the cancer cells while minimizing damage to the normal cell, and these therapies work in one in four ways. Some block the cancer cells from reproducing newer cells, others release toxic substances to kill the cancer cells, some stimulate the immune system to destroy the cancer cells, and some block the growth of more blood vessels around cancer cells, which starve the cells of the nutrients, which is needed for their growth. This review aims to testify the advancements nanotechnology has brought in cancer therapy, and its statements are supported with recent research findings and clinical trial results.
-
10.
High-mechanical strength carboxymethyl chitosan-based hydrogel film for antibacterial wound dressing.
Zhang, M, Yang, M, Woo, MW, Li, Y, Han, W, Dang, X
Carbohydrate polymers. 2021;:117590
Abstract
Hydrogels, being highly biocompatible and adaptable with biological tissues, have shown great usability in biomedical applications. In this research, a novel hydrogel film developed from carboxymethyl chitosan (CMCS) loaded with waterborne polyurethane-gelatin hydrolysate was synthesized via aqueous emulsion copolymerization. The synthesized hydrogel film was characterized using mechanical strength tests, FTIR, XPS, SEM, AFM, and various other analysis technologies. The results demonstrated that the hydrogel film exhibited good thermal stability, swelling behavior, as well as controllable biodegradability. Specifically, when the CMCS content was loaded at 6 %, the maximum tensile strength and elongation at the break of the hydrogel film were reached 31.69 MPa and 447.187, respectively. The disk diffusion tests indicated that the hydrogel film presented significant antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). These results indicate that hydrogel films with high mechanical strength and high antibacterial activity could be used for wound dressing applications.