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Topic Review
Biogenic Silver Nanoparticles
Biogenic silver nanoparticles are environmentally safer compared to particles obtained by chemical or physical methods due to the absence of toxic compounds in the technological process, gentle synthesis conditions and the possibility of utilizing the biomass used in their production. Biogenic silver nanoparticles are capable of self-assembly, including that on various surfaces, and there are mechanisms for controlling their morphology and size. Approaches and methods for obtaining biogenic silver nanoparticles using various parts of plants, algae, fungi and microorganisms have been described.
  • 783
  • 17 Dec 2021
Topic Review
Subcritical-Water Extraction of Natural Products
Subcritical water refers to high-temperature and high-pressure water, but below water's critical point of 374 °C and 218 atm. A unique and useful characteristic of subcritical water is that its polarity can be dramatically decreased with increasing temperature. Therefore, subcritical water can behave similarly to methanol or ethanol. This makes subcritical water a green extraction fluid used for a variety of organic species. 
  • 770
  • 09 Jul 2021
Topic Review
Antimicrobial Activity of Gemini Surfactants
Gemini cationic surfactants (GS) are constructed from two alkylammonium monomeric salts linked by a spacer.They exhibit significant surface, aggregation and antimicrobial properties. Due to the fact that, in order to achieve the desired utility effect, the minimal concentration of compounds are used, they are in line with the principle of greenolution (green evolution) in chemistry. The obtained results indicate that the synthesized compounds are effective microbicides with a broad spectrum of biocidal activity and are active against Escherichia coli, Staphylococcus aureus, yeast Candida albicans, molds Aspergillus niger and Penicillium chrysogenum. These compounds constitute a new, interesting class of microbicides with a broad spectrum of biocidal activity.
  • 768
  • 28 Jan 2022
Topic Review
Defining Blood Plasma and Serum Metabolome by GC-MS
Metabolomics uses advanced analytical chemistry methods to analyze metabolites in biological samples. The most intensively studied samples are blood and its liquid components: plasma and serum. Armed with advanced equipment and progressive software solutions, the scientific community has shown that small molecules’ roles in living systems are not limited to traditional “building blocks” or “just fuel” for cellular energy. 
  • 765
  • 06 Jan 2022
Topic Review
Biomedical Application of Carbon Dots
Carbon dots (CDs), which are a new category of carbon nanoparticles that consist of quasi-spherical, discrete fluorescent carbon nanomaterials with a diameter of less than 10 nm, have multiple advantages over semiconductor quantum dots (QDs), including high water solubility, low cost, excellent biocompatibility, chemically inertness, highly tunable photoluminescence and electrochemical luminescence. Because of their unique properties, carbon quantum dots (CQDs) have acquired significance in nano-chemistry, which has resulted in the discovery of CDD applications, especially in biomedical applications.            
  • 761
  • 01 Mar 2023
Topic Review
Keratin-Based Nanoparticles as Drug Delivery Carriers
Keratin is a structural protein of mammalian tissues and birds, representing the principal constituent of hair, nails, skin, wool, hooves, horns, beaks, and feathers, and playing an essential role in protecting the body from external harassment. Due to its intrinsic features such as biocompatibility, biodegradability, responsiveness to specific biological environment, and physical-chemical properties, keratin has been extensively explored in the production of nanocarriers of active principles for different biomedical applications.
  • 760
  • 25 Oct 2021
Topic Review
Cellulosic-Based Conductive Hydrogels for Electro-Active Tissues
The use of hydrogel in tissue engineering is not entirely new. In the last six decades, researchers have used hydrogel to develop artificial organs and tissue for the diagnosis of real-life problems and research purposes. Trial and error dominated the first forty years of tissue generation. Nowadays, biomaterials research is constantly progressing in the direction of new materials with expanded capabilities to better meet the current needs.
  • 759
  • 14 Mar 2022
Topic Review
Willardiine and Its Analogues
Willardiine was first identified by Rolf Gimelin in 1959 from the extracts of seeds of Acacia willardiana. Structurally it corresponds to (2S)-2-amino-3-(2,4-dioxopyrimidin-1-yl)propanoic acid (1) and carrying an uracil moiety it can be ascribed to the category of nucleoamino acids. Willardiine is synthesized by the single specific enzyme uracilylalanine synthase, and the N–heterocyclic moiety uracil obtained by the orotate pathway proved to be an effective bioisostere for the distal carboxyl group of L-glutamate. Different  aspects on both chemistry and biotechnological applications of willardine/willardine-analogues and nucleopeptides will be reviewed herein.
  • 758
  • 18 Oct 2022
Topic Review
Graphene Quantum Dots–Nanocellulose Composite
Graphene quantum dots (GQDs) are zero-dimensional carbon-based materials, while nanocellulose is a nanomaterial that can be derived from naturally occurring cellulose polymers or renewable biomass resources. The unique geometrical, biocompatible, and biodegradable properties of both these remarkable nanomaterials have caught the attention of the scientific community in terms of fundamental research to advanced technology. Studies have shown that the hybridisation of these novel materials not only improves existing applications but provides additional advantages as well as further improves desirable features, all of which are unattainable if GQDs and nanocellulose are used individually. Therefore, this advantageous composite material warrants remarkable applications. Potential applications for GQDs-nanocellulose composites include sensing or for analytical purposes, injectable 3D printing materials, supercapacitors, and light-emitting diodes. 
  • 757
  • 20 Oct 2021
Topic Review
Functionalized Lanthanide Oxide Nanoparticles
Functionalized lanthanide oxide (Ln2O3) nanoparticles has been used for tumor targeting, medical imaging, and therapy. Among the medical imaging techniques, magnetic resonance imaging (MRI) is an important noninvasive imaging tool for tumor diagnosis due to its high spatial resolution and excellent imaging contrast, especially when contrast agents are used. However, commercially available low-molecular-weight MRI contrast agents exhibit several shortcomings, such as nonspecificity for the tissue of interest and rapid excretion in vivo. Recently, nanoparticle-based MRI contrast agents have become a hot research topic in biomedical imaging due to their high performance, easy surface functionalization, and low toxicity. Among them, functionalized Ln2O3 nanoparticles are applicable as MRI contrast agents for tumor-targeting and nontumor-targeting imaging and image-guided tumor therapy. Primarily, Gd2O3 nanoparticles have been intensively investigated as tumor-targeting T1 MRI contrast agents. T2 MRI is also possible due to the appreciable paramagnetic moments of Ln2O3 nanoparticles (Ln = Dy, Ho, and Tb) at room temperature arising from the nonzero orbital motion of 4f electrons. In addition, Ln2O3 nanoparticles are eligible as X-ray computed tomography contrast agents because of their high X-ray attenuation power. 
  • 756
  • 22 Dec 2021
Topic Review
Sorbent-Based Microextraction of Natural Toxins from Food Samples
Natural toxins are chemical substances that are not toxic to the organisms that produce them, but which can be a potential risk to human health when ingested through food. Thus, it is of high interest to develop advanced analytical methodologies to control the occurrence of these compounds in food products. Current trends in sample preparation involve moving towards “greener” approaches by scaling down analytical operations, miniaturizing the instruments and integrating new advanced materials as sorbents. The combination of these new materials with sorbent-based microextraction technologies enables the development of high-throughput sample preparation methods, which improve conventional extraction and clean-up procedures.
  • 744
  • 05 Nov 2021
Topic Review
PAMAM-calix-dendrimers
A convenient method for the synthesis of the first generation PAMAM dendrimers based on the thiacalix[4]arene has been developed for the first time. Three new PAMAM-calix-dendrimers with the macrocyclic core in cone, partial cone, and 1,3-alternate conformations were obtained with high yields.
  • 743
  • 11 Nov 2021
Topic Review
Research Status of Graphene Polyurethane Composite Coating
Graphene material has a variety of excellent properties and applications in energy storage, biomaterials, photoelectric devices, and other fields. With the progress of nanotechnology, graphene nanomaterials have shown their advantages in the field of new nano-corrosion coatings with their high barrier structure. In addition, polyurethane is also widely used in the field of anti-corrosion coatings due to its excellent chemical resistance, mechanical properties, and weathering resistance. The preparation of composite coatings by combining graphene nanomaterials with traditional polyurethane (PU) coatings has opened up a new way for the research and development of new anticorrotic coatings.
  • 742
  • 22 Feb 2022
Topic Review
Nanomaterial Probes for Nuclear Imaging
Nuclear imaging is a powerful non-invasive imaging technique that is rapidly developing in medical theranostics. Nuclear imaging requires radiolabeling isotopes for non-invasive imaging through the radioactive decay emission of the radionuclide. Nuclear imaging probes, commonly known as radiotracers, are radioisotope-labeled small molecules. Nanomaterials have shown potential as nuclear imaging probes for theranostic applications. By modifying the surface of nanomaterials, multifunctional radio-labeled nanomaterials can be obtained for in vivo biodistribution and targeting in initial animal imaging studies. Various surface modification strategies have been developed, and targeting moieties have been attached to the nanomaterials to render biocompatibility and enable specific targeting. Through integration of complementary imaging probes to a single nanoparticulate, multimodal molecular imaging can be performed as images with high sensitivity, resolution, and specificity. 
  • 732
  • 29 Mar 2022
Topic Review
Melatonin/Cyclodextrin Inclusion Complexes
Melatonin (MLT) is involved in many functions of the human body, mainly in sleeping-related disorders. It also has anti-oxidant potential and has been proven very effective in the treatment of seasonal affective disorders (SAD), which afflict some people during short winter days. Melatonin has been implicated in a range of other conditions, including Parkinson’s disease, Alzheimer’s and other neurological conditions, and in certain cancers. Its poor solubility in water leads to an insufficient absorption that led scientists to investigate MLT inclusion in cyclodextrins (CDs), as inclusion of drugs in CDs is a way of increasing the solubility of many lipophilic moieties with poor water solubility. 
  • 729
  • 17 Jan 2022
Topic Review
Recent Advances in the Development of Fire-Resistant Biocomposites
Biocomposites reinforced with natural fibers represent an eco-friendly and inexpensive alternative to conventional petroleum-based materials and have been increasingly utilized in a wide variety of industrial applications due to their numerous advantages, such as their good mechanical properties, low production costs, renewability, and biodegradability. However, these engineered composite materials have inherent downsides, such as their increased flammability when subjected to heat flux or flame initiators, which can limit their range of applications. As a result, certain attempts are still being made to reduce the flammability of biocomposites. The combustion of biobased composites can potentially create life-threatening conditions in buildings, resulting in substantial human and material losses. Additives known as flame-retardants (FRs) have been commonly used to improve the fire protection of wood and biocomposite materials, textiles, and other fields for the purpose of widening their application areas. At present, this practice is very common in the construction sector due to stringent fire safety regulations on residential and public buildings. 
  • 727
  • 28 Jan 2022
Topic Review
Smart Drug Delivery
Drug delivery systems based on deformable peptides have been widely studied in tumor targeted therapy, for example, proton-driven tumor vaccine composed of deformable peptides for tumor immunotherapy, and an intracellular delivery system of chimeric peptides based on transmembrane peptides for acute liver injury in mice. With the help of software, researchers can take tiny strands of DNA and fold them into complex structures, complete with components such as rotors and hinges that can move and perform tasks, such as drug delivery and cargo handling. A nano-robot based on DNA origami technology can precisely locate tumor tissue and effectively inhibit tumor growth and metastasis.
  • 721
  • 08 Nov 2021
Topic Review
Dehydrogenases involved in Reduction of CO2 to CH3OH
The three dehydrogenase enzymes involved in the CO2 to methanol conversion are: Formate dehydrogenase, Formaldehyde dehydrogenase and Alcohol dehydrogenase.
  • 720
  • 26 Aug 2022
Topic Review
Encapsulated Natural Bioactive Compounds in Food Industry
Plants are the most abundant bioresources, providing valuable materials that can be used as additives in polymeric materials, such as lignocellulosic fibers, nano-cellulose, or lignin, as well as plant extracts containing bioactive phenolic and flavonoid compounds used in the healthcare, pharmaceutical, cosmetic, and nutraceutical industries. Bioactive packaging is developing to additionally provides antibacterial and antioxidant activity with the same goals i.e., extending the shelf life while ensuring safety of the food products. New solutions are designed using natural antimicrobial and antioxidant agents such as essential oils, some polysaccharides, natural inorganic nanoparticles (nanoclays, oxides, metals as silver) incorporated/encapsulated into appropriate carriers in order to be used in food packaging. Electrospinning/electrospraying are receiving attention as encapsulation methods due to their cost-effectiveness, versatility and scalability. The electrospun nanofibers and electro–sprayed nanoparticles can preserve the functionality and protect the encapsulated bioactive compounds (BC).
  • 718
  • 24 Dec 2021
Topic Review
General Aspects of Carbon Dot and Polymer Composites
Carbon dot-based composite materials have been extensively developed for versatile biomedical applications, such as drug delivery, tissue engineering, bioimaging, biosensors, and photothermal cancer therapy, owing to their excellent mechanical properties, electrical and thermal conductivity, large surface-to-volume ratio, and biocompatibility. For instance, the hydrophobicity and delocalized π-electrons of carbon dots enable insoluble drug loading in carbon composite-based drug delivery carriers. In addition, carbon dot-based materials are suitable for optical and electrochemical biosensor applications owing to their intrinsic properties.
  • 718
  • 01 Nov 2022
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