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Acta Pharmaceutica (Zagreb, Croatia) Jun 2022The first germanium compounds which exhibited immunomodulatory and antiviral effects were sesquioxane-type germanates. To date, more than a dozen compounds containing... (Review)
Review
The first germanium compounds which exhibited immunomodulatory and antiviral effects were sesquioxane-type germanates. To date, more than a dozen compounds containing germanium have been synthesized and are being actively studied. They include germanium carboxylates and citrates, complexes of germanium with resveratrol, daphnetin, mangiferin, chrysin, quercetin, ascorbic and nicotinic acids, amino acids, gamma-lactones, germanium-containing spirulina, yeast and others. Germanium-based compounds have shown the ability to influence the replication of various DNA/RNA viruses, stimulate the body's natural resistance, prevent the development of metabolic intoxication of various origin, increase the efficacy of vaccines, and prevent the development of excessive accumulation of reactive oxygen species, which plays a decisive role in the development of inflammatory response caused by a viral infection. It seems reasonable to say that germanium-based complex compounds effectively contribute to the preservation of high--energy bonds in the form of ATP, optimize the activity of metabolic processes by re-oxygenation, and exhibit antimicrobial activity. The purpose of this review is to summarize the pharmacological potential of various germanium-based compounds studied nowadays, taking into account their mechanisms of action, and to analyze their prospects in the development of integrated approaches in the prevention and treatment of SARS-CoV-2 infection.
Topics: Humans; COVID-19; Germanium; SARS-CoV-2; Antiviral Agents; Quercetin
PubMed: 36651511
DOI: 10.2478/acph-2022-0016 -
Journal of Translational Medicine Nov 2023With the development of organic germanium and nanotechnology, germanium serves multiple biological functions, and its potential value in biochemistry and medicine has... (Review)
Review
With the development of organic germanium and nanotechnology, germanium serves multiple biological functions, and its potential value in biochemistry and medicine has increasingly captured the attention of researchers. In recent years, germanium has gradually gained significance as a material in the field of biomedicine and shows promising application prospects. However, there has been a limited amount of research conducted on the biological effects and mechanisms of germanium, and a systematic evaluation is still lacking. Therefore, the aim of this review is to systematically examine the application of germanium in the field of biomedicine and contribute new insights for future research on the functions and mechanisms of germanium in disease treatment. By conducting a comprehensive search on MEDLINE, EMBASE, and Web of Science databases, we systematically reviewed the relevant literature on the relationship between germanium and biomedicine. In this review, we will describe the biological activities of germanium in inflammation, immunity, and antioxidation. Furthermore, we will discuss its role in the treatment of neuroscience and oncology-related conditions. This comprehensive exploration of germanium provides a valuable foundation for the future application of this element in disease intervention, diagnosis, and prevention.
Topics: Germanium; Nanotechnology
PubMed: 37940963
DOI: 10.1186/s12967-023-04643-0 -
Journal of Visualized Experiments : JoVE Dec 2011The development of hybrid electronic devices relies in large part on the integration of (bio)organic materials and inorganic semiconductors through a stable interface...
The development of hybrid electronic devices relies in large part on the integration of (bio)organic materials and inorganic semiconductors through a stable interface that permits efficient electron transport and protects underlying substrates from oxidative degradation. Group IV semiconductors can be effectively protected with highly-ordered self-assembled monolayers (SAMs) composed of simple alkyl chains that act as impervious barriers to both organic and aqueous solutions. Simple alkyl SAMs, however, are inert and not amenable to traditional patterning techniques. The motivation for immobilizing organic molecular systems on semiconductors is to impart new functionality to the surface that can provide optical, electronic, and mechanical function, as well as chemical and biological activity. Microcontact printing (μCP) is a soft-lithographic technique for patterning SAMs on myriad surfaces. Despite its simplicity and versatility, the approach has been largely limited to noble metal surfaces and has not been well developed for pattern transfer to technologically important substrates such as oxide-free silicon and germanium. Furthermore, because this technique relies on the ink diffusion to transfer pattern from the elastomer to substrate, the resolution of such traditional printing is essentially limited to near 1 μm. In contrast to traditional printing, inkless μCP patterning relies on a specific reaction between a surface-immobilized substrate and a stamp-bound catalyst. Because the technique does not rely on diffusive SAM formation, it significantly expands the diversity of patternable surfaces. In addition, the inkless technique obviates the feature size limitations imposed by molecular diffusion, facilitating replication of very small (<200 nm) features. However, up till now, inkless μCP has been mainly used for patterning relatively disordered molecular systems, which do not protect underlying surfaces from degradation. Here, we report a simple, reliable high-throughput method for patterning passivated silicon and germanium with reactive organic monolayers and demonstrate selective functionalization of the patterned substrates with both small molecules and proteins. The technique utilizes a preformed NHS-reactive bilayered system on oxide-free silicon and germanium. The NHS moiety is hydrolyzed in a pattern-specific manner with a sulfonic acid-modified acrylate stamp to produce chemically distinct patterns of NHS-activated and free carboxylic acids. A significant limitation to the resolution of many μCP techniques is the use of PDMS material which lacks the mechanical rigidity necessary for high fidelity transfer. To alleviate this limitation we utilized a polyurethane acrylate polymer, a relatively rigid material that can be easily functionalized with different organic moieties. Our patterning approach completely protects both silicon and germanium from chemical oxidation, provides precise control over the shape and size of the patterned features, and gives ready access to chemically discriminated patterns that can be further functionalized with both organic and biological molecules. The approach is general and applicable to other technologically-relevant surfaces.
Topics: Germanium; Microscopy, Fluorescence; Nanotechnology; Oxides; Proteins; Semiconductors; Silicon
PubMed: 22214997
DOI: 10.3791/3478 -
Research in Pharmaceutical Sciences Jul 2013The six elements commonly known as metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Metalloid containing compounds have been used as... (Review)
Review
The six elements commonly known as metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Metalloid containing compounds have been used as antiprotozoal drugs. Boron-based drugs, the benzoxaboroles have been exploited as potential treatments for neglected tropical diseases. Arsenic has been used as a medicinal agent and arsphenamine was the main drug used to treat syphilis. Arsenic trioxide has been approved for the treatment of acute promyelocytic leukemia. Pentavalent antimonials have been the recommended drug for visceral leishmaniasis and cutaneous leishmaniasis. Tellurium (IV) compounds may have important roles in thiol redox biological activity in the human body, and ammonium trichloro (dioxoethylene-O, O'-)tellurate (AS101) may be a promising agent for the treatment of Parkinson's disease. Organosilicon compounds have been shown to be effective in vitro multidrug-resistance reverting agents.
PubMed: 24019824
DOI: No ID Found -
Biomedicines May 2023Germanium is an essential microelement, and its deficiency can result in numerous diseases, particularly oncogenic conditions. Consequently, water-soluble germanium... (Review)
Review
Germanium is an essential microelement, and its deficiency can result in numerous diseases, particularly oncogenic conditions. Consequently, water-soluble germanium compounds, including inorganic and coordination compounds, have attracted significant attention due to their biological activity. The review analyzes the primary research from the last decade related to the anticancer activity of germanium compounds. Furthermore, the review clarifies their actual toxicity, identifies errors and misconceptions that have contributed to the discrediting of their biological activity, and briefly suggests a putative mechanism of germanium-mediated protection from oxidative stress. Finally, the review provides clarifications on the discovery history of water-soluble organic germanium compounds, which was distorted and suppressed for a long time.
PubMed: 37371629
DOI: 10.3390/biomedicines11061535 -
Journal of Materials Science. Materials... Jan 2021In this study, borosilicate glass and 316 L stainless steel were coated with germanium (Ge) and tungsten (W) metals using the Magnetron Sputtering System. Surface...
In this study, borosilicate glass and 316 L stainless steel were coated with germanium (Ge) and tungsten (W) metals using the Magnetron Sputtering System. Surface structural, mechanical, and tribological properties of uncoated and coated samples were examined using SEM, X-ray diffraction (XRD), energy-dispersive spectroscopy, and tribometer. The XRD results showed that WGe chemical compound observed in (110) crystalline phase and exhibited a dense structure. According to the tribological analyses, the adhesion strength of the coated deposition on 316 L was obtained 32.8 N, and the mean coefficient of friction was around 0.3. Biocompatibility studies of coated metallic biomaterials were analyzed on fibroblast cell culture (Primary Dermal Fibroblast; Normal, Human, Adult (HDFa)) in vitro. Hoescht 33258 fluorescent staining was performed to investigate the cellular density and chromosomal abnormalities of the HDFa cell line on the borosilicate glasses coated with germanium-tungsten (W-Ge). Cell viabilities of HDFa cell line on each surface (W-Ge coated borosilicate glass, uncoated borosilicate glass, and cell culture plate surface) were analyzed by using (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cytotoxicity assay. The antibiofilm activity of W-Ge coated borosilicate glass showed a significant reduction effect on Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) adherence compared to control groups. In the light of findings, tungsten and germanium, which are some of the most common industrial materials, were investigated as biocompatible and antimicrobial surface coatings and recommended as bio-implant materials for the first time.
Topics: Biocompatible Materials; Biofilms; Cell Survival; Coated Materials, Biocompatible; Corrosion; Crystallography, X-Ray; Fibroblasts; Germanium; Humans; Materials Testing; Microbial Sensitivity Tests; Microscopy, Electron, Scanning; Pseudomonas aeruginosa; Stainless Steel; Staphylococcus aureus; Surface Properties; Titanium; Tungsten; X-Ray Diffraction
PubMed: 33471227
DOI: 10.1007/s10856-020-06477-4 -
Nanomaterials (Basel, Switzerland) Aug 2022Germanium (Ge) chalcogenides are characterized by unique properties which make these materials interesting for a very wide range of applications, from phase change...
Germanium (Ge) chalcogenides are characterized by unique properties which make these materials interesting for a very wide range of applications, from phase change memories to ovonic threshold switches, from photonics to thermoelectric and photovoltaic devices [...].
PubMed: 36079963
DOI: 10.3390/nano12172925 -
Chemical Science Mar 2021Once considered as mere curiosities, acyl metalloids are now recognized for their utility in enabling chemical synthesis. This perspective considers the reactivity... (Review)
Review
Once considered as mere curiosities, acyl metalloids are now recognized for their utility in enabling chemical synthesis. This perspective considers the reactivity displayed by acylboron, -silicon, -germanium, and tellurium species. By highlighting the role of these species in various transformations, we demonstrate how differences between the comprising elements result in varied reaction outcomes. While acylboron compounds are primarily used in polar transformations, germanium and tellurium species have found utility as radical precursors. Applications of acylsilanes are comparatively more diverse, owing to the possibility to access both radical and polar chemistry.
PubMed: 34163766
DOI: 10.1039/d1sc00077b -
Molecules (Basel, Switzerland) Feb 2023In this review, the latest achievements in the field of multiply bonded organogermanium derivatives, mostly reported within the last two decades, are presented. The... (Review)
Review
In this review, the latest achievements in the field of multiply bonded organogermanium derivatives, mostly reported within the last two decades, are presented. The isolable Ge-containing analogues of alkenes, alkynes, 1,3-dienes, allenes, and vinylidenes are discussed, and for each class of unsaturated organogermanium compounds, the most representative examples are given. The synthetic approaches toward homonuclear multiply bonded combinations solely consisting of germanium atoms, and their heteronuclear variants containing germanium and other group 14 elements, both acyclic and cyclic, are discussed. The peculiar structural features and nonclassical bonding nature of the abovementioned compounds are discussed based on their spectroscopic and structural characteristics, in particular their crystallographic parameters (double bond length, -bending at the doubly bonded centers, and twisting about the double bond). The prospects for the practical use of the title compounds in synthetic and catalytic fields are also briefly discussed.
Topics: Alkenes; Alkynes; Germanium; Alkadienes
PubMed: 36838546
DOI: 10.3390/molecules28041558 -
Optics Express Jul 2020The bandwidth and saturation power of germanium photodetectors are two crucial parameters for implementing analog and microwave photonics circuits. In conventional...
The bandwidth and saturation power of germanium photodetectors are two crucial parameters for implementing analog and microwave photonics circuits. In conventional schemes, it is hard to optimize these two parameters simultaneously, due to different requirements for the size of absorption region. We report the design and demonstration of a high-power and high-speed germanium photodetector with distributed absorption regions. In this distributed-absorption photodetector (DAPD), the junction is formed by a multiple absorption region (n-cell) on a mutual substrate, and the input light is split and fed into the n cells. A comprehensive theoretical model is developed, and the device bandwidth and power loss in aspect of the number of cells is discussed. Experimentally, 2-, 4- and 8-cell DAPDs are investigated, and the 2-cell scheme shows the superior performance with the radio-frequency saturation photocurrent as high as 16.1 mA and the 3 dB bandwidth as high as 50 GHz. Without changing the standard process in the silicon photonic foundry, the DAPD can be seamlessly integrated with other photonics devices, and it is very attractive to applications such as integrated microwave photonics systems.
PubMed: 32680052
DOI: 10.1364/OE.390079