Chemical Synthesis Method Research Articles

Superfast desulfurization for protein chemical synthesis and modification

Superfast desulfurization for protein chemical synthesis and modification

Zinc Phosphate Nanoparticles: A Review on Physical, Chemical, and Biological Synthesis and their Applications.

Nanotechnology is considered one of the emerging fields of science that has influenced diverse applications, including food, biomedicine, and cosmetics. The production and usage of materials with nanoscale dimensions like nanoparticles are attractive parts of nanotechnology. Among different nanoparticles, zinc phosphate nanoparticles have attracted attention due to their biocompatibility, biosafety, non-toxicity, and environmental compatibility. These nanoparticles could be employed in various applications like anticorrosion, antibacterial, dental cement, glass ceramics, tissue engineering, and drug delivery. A variety of physical, chemical, and green synthesis methods have been used to synthesize zinc phosphate nanoparticles. All these methods have some limitations along with certain advantages. Chemical approaches may cause health risks and environmental problems due to the toxicity of hazardous chemicals used in these techniques. Moreover, physical methods require high amounts of energy as well as expensive instruments. However, biological methods are free of chemical contaminants and eco-friendly. This review is aimed to explore different methods for the synthesis of zinc phosphate nanoparticles, including physical, chemical, and more recently, biological approaches (using various sources such as plants, algae, and microorganisms). Also, it summarizes the practicable applications of zinc phosphate nanoparticles as anticorrosion pigment, dental cement, and drug delivery agents.

Electrochemically Prepared Polyaniline as an Alternative to Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) for Inverted Perovskite Solar Cells

The goal of this work is to substitute the conventional high-cost poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) in inverted perovskite solar cells (PSCs) with an efficient and conducting polyaniline (PANI) polymer. The reported use of PANI in PSCs involves a chemical synthesis method which is prone to contamination with impurities as it requires several materials for polymerization and adhesion improvement with substrates, contributing to low device efficiencies. This work mitigates this issue using an electrochemical method that is low cost, less time consuming, and capable of producing thin films of PANI with excellent adhesion to substrates. Results demonstrated that the power conversion efficiency of the electrochemically synthesized PANI-based PSC is 16.94% versus 15.11% for the PEDOT:PSS-based device. It was observed that the work function of PANI was lower compared to that of PEDOT:PSS which decreased VOC but enhanced hole extraction at the hole transport layer/perovskite interface, thus increasing JSC. Doping electrolyte solution with lithium bis(trifluoromethanesulfonyl)imide LiTFSI increased the work function of PANI, thus increasing VOC from 0.87 to 0.93 V. This method enables simple and scalable synthesis of PANI as a competitive hole transport material to replace rather expensive PEDOT:PSS, thus enabling an important step toward low-cost inverted perovskite photovoltaic devices.

Microbe-fabricated nanoparticles as potent biomaterials for efficient food preservation

In recent years, cutting-edge nanotechnology research has revolutionized several facets of the food business, including food processing, packaging, transportation, preservation, and functioning. Nanotechnology has beginning to loom large in the food business as the industry's demand for biogenic nanomaterial grows. The intracellular and extracellular synthesis of metal, metal oxide, and other essential NPs has recently been explored in a variety of microorganisms, including bacteria, actinomycetes, fungi, yeasts, microalgae, and viruses. These microbes produce a variety extracellular material, exopolysaccharides, enzymes, and secondary metabolites which play key roles in synthesizing as well as stabilizing the nanoparticle (NPs). Furthermore, genetic engineering techniques can help them to improve their capacity to generate NPs more efficiently. As a result, using microorganisms to manufacture NPs is unique and has a promising future. Microbial-mediated synthesis of NPs has lately been popular as a more environmentally friendly alternative to physical and chemical methods of nanomaterial synthesis, which require higher prices, more energy consumption, and more complex reaction conditions, as well as a potentially dangerous environmental impact. It is critical to consider regulatory measures implemented at all stages of the process, from production through refining, packaging, preservation, and storage, when producing bionanomaterials derived from culturable microbes for efficient food preservation. The current review discusses the synthesis, mechanism of action, and possible food preservation uses of microbial mediated NPs, which can assist to minimize food deterioration from the inside out while also ensuring that food is safe and free of contaminants. Despite the numerous benefits, there are looming debates concerning their usage in food items, particularly regarding its aggregation in human bodies and other risks to the environment. Other applications and impacts of these microbe-fabricated NPs in the context of future food preservation prospects connected with regulatory problems and potential hazards are highlighted.

Recent advances in morphologically controlled synthesis of graphene oxide‐based nanocomposite as catalyst and fuel additive

Recent advances in morphologically controlled synthesis of graphene oxide‐based nanocomposite as catalyst and fuel additive

(Digital Presentation) Engineering Band Gap of Chalcogenide Nanomaterial-Polymer Composites

Over the last two decades, engineering the optical properties of nanoscale structures (nanowires, quantum dots, and nanotubes), i.e., band gap, absorption, and photoluminescence radiation, which can be manipulated in sulfide-based semiconductor materials, has received a lot of attention. Due to their tunable characteristics, these materials were introduced for potential applications ranging from medicine and communications to energy and various sensors (1). In addition, chemical synthesis methods provide the desired structure, material, reproducibility, and possibility of large-scale production, along with sustainable industrialization and foster innovation of these material systems. Polyvinyl-alcohol (PVA) is one of the functional polymers, in addition to the ability to stabilize the nanomaterial solution, which can change the optical properties of the material (2). Currently, the majority of sulfide-based nanomaterials are cadmium, lead, and silver, which have shown a wide range of applications. Here, PVA/CdS, PVA/PbS, and PVA/Ag2S nanocomposites were investigated as the desired composites. For optical studies, band gap, absorption, and photoluminescence irradiation of these material systems were performed. The structural and morphological properties were examined by scanning electron microscopy, DLS, and X-ray diffraction. The band gap value of synthesized nanoparticles in the polymer bed was 3.48, 3.08, and 2.27 eV for PVA/CdS, PVA/PbS, and PVA/Ag2S, respectively, whereas for pure PVA the band gap value was 4.75 eV. As shown in Figure 1, with the entry of nanoparticles into the polymer, a shift in the composite band gap can be seen that corresponds to an increase in absorption. Photoluminescence irradiations for polymer-nanoparticle composites showed that silver-polymer nanoparticles have intense irradiance at 405nm, while cadmium-polymer and lead-polymer composites have intense irradiance at 430nm and 500nm, respectively. An X-ray diffraction pattern was indicated for each of the crystals, confirming the presence of the expected crystal structure. The DLS of materials represents sizes of 150, 125, and 175 nm for PVA/CdS, PVA/PbS, and PVA/Ag2S. Besides, the structure of the material systems was examined by FE-SEM microscopy, which showed a homogeneous distribution of particles in the polymer and a cubic nanoparticle structure for PVA/PbS and a spherical for PVA/Ag2S and PVA/CdS. Our findings show that polymer-nanomaterial composites are potential candidates for use in sensors and solar energy cells, especially non-toxic Ag2S nanomaterials (3) that have already been documented as an emerging platform for in-vivo imaging.

Solution-Phase Syntheses and Photochemical Properties of Silver Bismuth Sulfide Nanoparticles

Introduction When semiconductor nanoparticles are reduced to a size of several nanometers or less, the physico-chemical properties start to change by the quantum confinement. The energy gap of particles is enlarged and their absorption spectrum is blue-shifted with a decrease in the particle size. These nanoparticles have been intensively investigated for developing efficient light energy conversion systems, such as photocatalysts [1] and photovoltaics [2]. Especially, high-efficiency quantum dot solar cells fabricated with PbS and PbSe nanoparticles, which showed the responsivity in near-IR region, have attracted much attention [3]. However, the contents of highly toxic element, Pb and Se, limit their use in a wide range of applications [4].Recently, a multinary AgBiS2 semiconductor can absorb visible and near-IR lights and seems to be a promising material for efficient light energy conversion [5], but there are few reports to prepare size-quantized nanoparticles and control their particle size. In this study, we report the preparation of AgBiS2 nanoparticles using a liquid-phase chemical synthesis method. Their size was varied depending on the preparation conditions. Furthermore, we investigated their photoelectrochemical properties as functions of particle size and composition. Experimental Precursors of bismuth acetate (Bi(OAc)3), silver acetate (Ag(OAc)), and sulfur powder, were dispersed in a mixture solvent of 1-dodecanethiol (DDT) and oleylamine (OLAm), followed by the heat treatment at 373, 393, 423 or 473 K for 30 min. Thus-obtained AgBiS2 nanoparticles were isolated by the addition of methanol as a non-solvent. Results and Discussion The particle size and composition of AgBiS2 nanoparticles were controlled by changing the heating temperature. With an increase of the heating temperature from 373 K to 473 K, the particle size was enlarged from 3.2 nm to 8.1 nm, accompanied by the increase of the Ag fraction in nanoparticles to the stoichiometric value. The onset wavelength in the absorption spectra of AgBiS2 nanoparticles was shifted from 1000 nm to 1200 nm with an increase in the particle size, resulting in the decrease of bandgap from 1.45 eV to 1.05 eV. Since the estimated bandgap values were larger than that of the bulk AgBiS2 (0.80 eV) [6], it was found that the obtained AgBiS2 nanoparticles showed a quantum size effect. The XRD analysis revealed that the obtained nanoparticles exhibited the cubic AgBiS2 crystal structure, regardless of the reaction temperature.The Ag/Bi ratio in the preparation also changed the particle size of obtained AgBiS2 nanoparticles as well as their chemical composition. By reacting precursors with Ag/(Ag+Bi) = 0.33 at 423 K, almost stoichiometric AgBiS2 nanoparticles were formed, that is, Ag: Bi: S = 1: 1: 2. In contrast, when Ag/(Ag+Bi) ratio in preparation was decreased from 0.5 to 0.25, the Ag fraction in nanoparticles decreased from the stoichiometric value of Ag/Bi=1, that is, non-stoichiometric AgBiS2 nanoparticles were formed. The particle size tended to decrease with a decrease in the Ag/(Ag+Bi) ratio in preparation.We carried out the photoelectrochemical measurement of AgBiS2 nanoparticles immobilized on ITO electrodes. Anodic or cathodic photocurrents were detected, depending on the Ag fraction in nanoparticles. The energy levels of AgBiS2 nanoparticles were determined by measuring the photoelectron yield spectroscopy in air. The onset potentials of photocurrent generation were significantly different from the levels of conduction band minimum or valence band maximum, suggesting that the thus-obtained AgBiS2 nanoparticles contained the large amount of defect sites which acted as a carrier recombination site. Acknowledgments This work is supported by the New Energy and Industrial Technology Development Organization (NEDO). References (1) S. Chen, D. Huang, P. Xu, W. Xue, L. Lei, M. Cheng, R. Wang, X. Liu, and R. Deng., J. Mater. Chem. A, 8, 2286 (2020).(2) G. H. Carey, A. L. Abdelhady, Z. Ning, S. M. Thon, O. M. Bakr, and E. H. Sargent, Chem. Rev., 115, 12732 (2015).(3) H. Lee, H. J. Song, M. Shim, and C. Lee, Energy Environ. Sci., 13, 404 (2020).(4) F. M. Winnik and D. Maysinger, Acc. Chem. Res., 46, 672 (2013).(5) M. Bernechea, N. Miller, G. Xercavins, D. So, A. Stavrinadis, and G. Konstantatos, Nat. Photonics, 10, 521 (2016).(6) S. N. Guin and K. Biswas, Chem. Mater., 25, 3225 (2013).

(Organic and Biological Electrochemistry Division Manuel M. Baizer Award, Digital Presentation) Electron-Transfer-Triggered Smart Reactions Boost a Better Anthropocene

It is important that chemical reactions initiated by electron transfer associated with electrodes can be achieved by precise control of intramolecular and intermolecular electron transfer of organic compounds, which is difficult to achieve by general chemical methods. Expectations for a new production process that positively controls the electron transfer is also expanding dramatically. Here, the solvent that dissolves the substrate for reaction, the network structure of the ionic species in the solution, and the role of coexisting substances are exactly grasped, and the total energy consumption is controlled under milder conditions. If it is possible to develop a chemical process that reduces the consumption of substances such as reaction reagents to the utmost while significantly suppressing the above, it is expected that structural conversion of chemical substances based on the electron transfer process can be realized. This means that advanced control of the formation, stabilization, and subsequent reactions of active open-shell molecules opens the door to new chemical reactions that reduce excess reagent and energy consumption. There is a possibility that the atom economy will be dramatically enhanced by the electron transfer reaction process for the reagents that need to be charged. This achieves a chemical reaction that is regarded as "Electrons as Reagents", and it will be a core technology that will bring about innovation in the chemical substance manufacturing method that is currently produced with the production of a large amounts of unnecessary substances and energy consumption. Research achievements: In such a background, K. Chiba pioneered original organic electrolytic reactions based on the research activities on chemical synthesis of biologically active natural compounds, and achieved various carbon skeleton formation, chemical synthesis of useful substances and biologically active natural substances. One of the notable results is the electrolytic synthesis reaction method using a unique electrolyte solution composed of lithium perchlorate / nitromethane. It was shown that the cation species generated by electrode electron transfer using this electrolyte solution are stabilized and can be applied to the formation of a wide variety of intermolecular carbon-carbon bonds. That is, numerous electrode process-triggered reactions such as varied (hetero)Diels-Alder reactions, [3+2], and [2+2] cycloaddition reactions have been achieved. In addition, the olefin metathesis without transition metal catalysis was successful for the first time. The importance of the role of the electrolyte solution in the organic electrolysis reaction was widely shown. The elucidation of these reaction mechanisms and new findings on the action of the reaction field have contributed to the rapid development of the field in recent years by utilizing and enhancing the functions of various electrolyte solutions.In addition, the application of the new organic electrolysis method has widely developed chemical synthesis methods for natural and non-natural peptides, artificial nucleic acids, etc. It is noteworthy that it was successful in electrolytic synthesis of various aza-nucleosides by utilizing the cation species under the stabilizing action of the lithium perchlorate / nitromethane electrolyte solution. This basic skeleton paves the way for mass synthesis of nucleic acid derivatives, which are promising as therapeutic drug for covid-19.Furthermore, K. Chiba achieved organic electrolytic reactions that mimic the electron transfer process in the living body. Inspired by the bio-mimic chemical reaction system, he proposed a chemical process based on biphasic solutions. The key technology is the introduction of a solution system that combines a highly polar electrolyte solution and a hydrophobic organic solvent. By controlling the temperature, phase-fusion and phase-separation can be repeated, so that the product, for example, can be taken out from the reaction system while reusing the electrolyte solution. By forming reverse micelles in a hydrophobic solvent, a continuous reaction system can be constructed, which has led to the proposal of an important method for industrial application of electrolytic reactions and of multi-step medium-size molecule syntheses reducing environmental load. Outlook for the future: We must achieve a more efficient cycle of material, food and energy to support the world's population of 9 billion in the near future. For that purpose, it is extremely important to pay attention to and apply the functions of electrons involved in the production and decomposition of all chemical substances, including the elucidation and utilization of biological functions. The key technology of controlling electron transfer is indispensable for achieving a smart green society boosting a better Anthropocene.

(Invited, Digital Presentation) Transformations of Ionic Nanocrystals Via Ion Exchange Reactions

Elaborate chemical synthesis methods allow the production of various types of inorganic nanocrystals (NCs) with uniform shape and size distributions. Then, how can we synthesize NCs with thermodynamically metastable phases or very complex structures? The transformation of already-synthesized NCs via elemental substitutions, such as ion exchange reactions for ionic NCs [1,2] and galvanic replacement reactions for metal NCs [3], can overcome the difficulties facing conventional one-step syntheses. In particular, NC ion exchange reactions have been studied with numerous combinations of foreign ions and ionic NCs with various shapes. The functionality of the resulting ionic NCs, including semiconducting and plasmonic properties, can be easily tuned in a wide range, from the visible to near-infrared. Here we focus on the full and partial ion exchange reactions involving ionic NCs, highlighting important aspects such as the preservation of appearance and dimensions [4,5]. Finally, visible-to-near infrared light energy conversion systems using partially exchanged ionic NCs are provided [6,7].[1] Saruyama, M.; Sato, R.; Teranishi, T. Acc. Chem. Res. 2021, 54, 765.[2]Saruyama, M.; Teranishi, T. et al., J. Am. Chem. Soc. 2011, 133, 17598.[3] Sato, R.; Teranishi, T. et al., to be submitted.[4] Wu, H.-L.; Teranishi, T. et al., Science 2016, 351, 1306.[5] Li, Z.; Saruyama, M.; Asaka, T.; Tatetsu, Y.; Teranishi, T. Science 2021, 373, 332.[6] Lian, Z.; Teranishi, T. et al., Nat. Commun. 2018, 9, 2314.[7] Lian, Z.; Teranishi, T. et al., J. Am. Chem. Soc. 2019, 141, 2446.

A novel experimental and statistical study on ethylene glycol-based nanofluid enriched by MWCNT and CuO nanoparticles

In this study, the viscosity (μnf) of enriched ethylene–glycol (EG) by MWCNT and CuO (30 % −70 %) hybrid nanoparticles is experimentally and statistically investigated. For this purpose, MWCNTs are synthesized via the wet chemical synthesis method. Then, targeted NF is prepared in solid volume fractions (SVFs) 0.01, 0.02, 0.05, 0.1 and 0.25 %, and T = 25–50 °C, as well as their rheological behavior, is studied. According to the results, investigated NF has dual behavior in different SVFs. It has non-Newtonian behavior at SVF of 0.25 % and Newtonian behavior at other SVFs. Also, sensitivity analysis proved that the μnf of MWCNT-CuO (30 % −70 %) / EG is so sensitive to the changes in SVFs but it shows very little sensitivity to the temperature. Furthermore, a new correlation is proposed according to the data of experiments for the prediction of μnf that can make optimal use of time and reduce experimental costs. The convergence factor (R2 = 0.96709) of mathematical-based correlation to experimental results is acceptable and satisfactory. Reduction of μnf in all SVFs from 0.01 % −0.1 % in comparison to pure EG is another interesting experimental finding in the present study.

PH-responsive glycine functionalized magnetic iron oxide nanoparticles for SARS-CoV-2 RNA extraction from clinical sample.

The recent outbreak of the novel corona virus disease 2019 (COVID-19) has been made a serious global impact due to its high infectivity and severe symptoms. The Severe Acute Respiratory Syndrome (SARS-CoV-2) RNA extraction is considered as one of the most important steps in COVID-19 detection. Several commercially available kits and techniques are currently being used for specific extraction of SARS-CoV-2 RNA. However, such methods are time consuming and expensive due to the requirement of trained labors, and several chemical reagents. To overcome the mentioned limitations, magnetic RNA adsorption methodology of glycine functionalized iron oxide nanoparticles (GNPs) was established. It showed an efficient potential in SARS-CoV-2 RNA extraction due to pH responsive nature of GNPs. The highly magnetic pH responsive GNPs were synthesized by one-pot co-precipitation method. Random morphology and average 20 nm size of GNPs were denoted by Transmission Electron Microscopy (TEM). X-ray diffractometer (XRD) showed the crystalline magnetite nature. Fourier transform infrared spectroscopy (FT-IR) and UV–visible spectrometry confirmed the presence of glycine on the surface of magnetic nanoparticles. Furthermore, the magnetic nature and thermal properties of GNPs were examined by vibrating sample magnetometer (VSM) and thermo-gravimetric analysis (TGA), respectively. In this study, glycine performed the role of RNA adsorbent. The adsorption of RNA onto the surface of GNPs was achieved in acidic medium (pH 6). In contrary, the elution of RNA from the surface of GNPs was achieved in basic medium (pH 8). The purity of obtained RNA was analyzed by UV–visible spectrometry. Further, the obtained RNA was examined for the presence of SARS-CoV-2 specific Envelope (E), RNA dependent RNA polymerase (RDRP) and Nucleocapsid (N) genes using an RT-PCR analysis. It showed the sudden rise in amount of these genes after 25 cycles of RT-PCR and hence indicated the efficient RNA extraction by GNPs. Agarose gel electrophoresis was used for validation of the quantity and quality of RNA extracted from SARS-CoV-2 patient’s sample. The reusability studies of GNPs were performed by monitoring the repeated use of GNPs for SARS-CoV-2 RNA extraction. This method possesses potential role in the field of disease diagnosis. The extraction results of RNA from SARS-CoV-2 patient’s sample indicated that the GNPs have an outstanding property over the current existing extraction protocols. It leads to the new advancements in extraction and detection of RNA.Graphical Graphical abstract of the pH responsive SARS-CoV-2 RNA extraction by using glycine functionalized magnetic iron oxide nanoparticles (GNPs) which were prepared by modified cost effective one pot chemical synthesis method. Prepared GNPs were characterized by XRD, FT-IR and UV-Visible spectrometry, Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Glycine present on the surface of nanoparticles (NPs) played an important role in pH responsive RNA extraction procedure. When nanoparticles added in acidic (pH < 7) medium, glycine gained positive surface charge hence overall surface charge of NPs became positive. Thereby SARS-CoV-2 RNA adsorption/binding occurred on the surface of GNP. Later, the RNA-GNP complex was separated by an external magnet. Separated complex was added in basic (pH > 7) medium to elute RNA from GNP. This phenomenon occurred due to surface negative charge of glycine that caused charge repulsion with RNA. Eluted RNA was examined qualitatively and quantitatively by RT-PCR, nanodrop technique and agarose gel electrophoresis. Results were compared with kit based extracted RNA. Supplementary InformationThe online version contains supplementary material available at 10.1007/s10853-022-07464-6.

Photoluminescence Properties of (Mg\(^{2+}\)) Divalent and (Al\(^{3+}\)) Trivalent Metal Coumarinolates Doped with Quinoline for PCLED Application

Several Mg-Coumarinolates and Al-Coumarinolates doped with different concentrations of Quinoline were synthesized by simple chemical synthesis method and their PL spectra were studied. Usually, pure coumarin along with the chelates show weak luminescence and the emission is witnessed around 450 nm with excitation around 350 nm. Hence, such chelates do not find any practical applications. Addition of quinoline in lesser amount affects the emission and excitation of Mg-Coumarin and Al-Coumarin considerably. Intense photoluminescence is observed in these Mg based mixed chelates. In all samples, a well-defined emission band at 490 nm is observed with broad excitation in 350 nm to 470 nm range. Hence good overlap of excitation with 420 nm and 440 nm LED emission makes these materials suitable for white LED applications.

One Pot Green Synthesis and Structural Characterisation of Bio-Silver Nanoparticles Using Prunus Persica L.

The Plant mediated green synthesis of nanoparticles has attracted more attention among the researchers due to their physicochemical and biological properties and their immense applications in environmental, biomedical, agriculture, textile, and energy storage. The biosynthesis of nanoparticles using plants provides more advantages such as easy operation, eco-friendly, utilization of non-hazardous chemicals, less temperature or energy usage, etc. when compared to physical and chemical synthesis methods. In the present study, we propose aqueous extracts from the endemic-medicinal fruit Prunus persica L. as an efficient bioproduct for the green synthesis of silver - nanoparticles (AgNPs). The biosynthesized AgNPs were characterized using UV-Visible spectroscopy, Fourier transforms Infrared spectroscopy (FTIR) High-Resolution Transmission electron microscopy (HR-TEM), Scanning electron microscopy, Atomic Force Microscopy (AFM), and X-ray diffractometer (XRD). HR-TEM gives the formation of monodispersed spherical shape with a mean diameter of 12.6 ± 3.8 nm. The SAED pattern of the nanoparticles showed that the particles were highly crystalline in nature. The purity of the synthesized AgNPs samples was studied by EDS and confirmed the presence of Ag elements corresponding to TEM images. The 2D and 3D structure images of the nanoparticle were studied and the average particle size calculation has been performed using NOVA-TX software in AFM. X-ray diffraction analysis showed that the particles were crystalline in nature with face - centered cubic structure. The antimicrobial efficacy was evaluated using the resazurin assay against both Escherichia coli and Bacillus subtilis bacteria. The antimicrobial assay of the silver nanoparticles showed higher activity against Bacillus subtilis than Escherichia coli. Results confirmed this protocol as rapid, simple, eco-friendly and alternative to conventional physical, and chemical methods.&#x0D;

Coumarin Derivatives Inhibit ADP-Induced Platelet Activation and Aggregation

Coumarin was first discovered in Tonka bean and then widely in other plants. Coumarin has an anticoagulant effect, and its derivative, warfarin, is a vitamin K analogue that inhibits the synthesis of clotting factors and is more widely used in the clinical treatment of endovascular embolism. At present, many artificial chemical synthesis methods can be used to modify the structure of coumarin to develop many effective drugs with low toxicity. In this study, we investigated the effects of six coumarin derivatives on the platelet aggregation induced by adenosine diphosphate (ADP). We found that the six coumarin derivatives inhibited the active form of GPIIb/IIIa on platelets and hence inhibit platelet aggregation. We found that 7-hydroxy-3-phenyl 4H-chromen-4-one (7-hydroxyflavone) had the most severe effect. In addition, we further analyzed the downstream signal transduction of the ADP receptor, including the release of calcium ions and the regulation of cAMP, which were inhibited by the six coumarin derivatives selected in this study. These results suggest that coumarin derivatives inhibit coagulation by inhibiting the synthesis of coagulation factors and they may also inhibit platelet aggregation.

Novel Unspecific Peroxygenase from Truncatella angustata Catalyzes the Synthesis of Bioactive Lipid Mediators.

Lipid mediators, such as epoxidized or hydroxylated eicosanoids (EETs, HETEs) of arachidonic acid (AA), are important signaling molecules and play diverse roles at different physiological and pathophysiological levels. The EETs and HETEs formed by the cytochrome P450 enzymes are still not fully explored, but show interesting anti-inflammatory properties, which make them attractive as potential therapeutic target or even as therapeutic agents. Conventional methods of chemical synthesis require several steps and complex separation techniques and lead only to low yields. Using the newly discovered unspecific peroxygenase TanUPO from the ascomycetous fungus Truncatella angustata, 90% regioselective conversion of AA to 14,15-EET could be achieved. Selective conversion of AA to 18-HETE, 19-HETE as well as to 11,12-EET and 14,15-EET was also demonstrated with known peroxygenases, i.e., AaeUPO, CraUPO, MroUPO, MweUPO and CglUPO. The metabolites were confirmed by HPLC-ELSD, MS1 and MS2 spectrometry as well as by comparing their analytical data with authentic standards. Protein structure simulations of TanUPO provided insights into its substrate access channel and give an explanation for the selective oxyfunctionalization of AA. The present study expands the scope of UPOs as they can now be used for selective syntheses of AA metabolites that serve as reference material for diagnostics, for structure-function elucidation as well as for therapeutic and pharmacological purposes.

Engineered Microbial Cell Factories for Sustainable Production of L-Lactic Acid: A Critical Review

With the increasing demand for the biodegradable polymer material polylactic acid and its advantage of being metabolized by the human body, L-lactic acid (L-LA) is becoming increasingly attractive in environmental protection and food industry applications. However, the supply of L-LA is not satisfied, and the price is still high. Compared to enzymatic and chemical synthesis methods, L-LA production by microbial fermentation has the advantages of low cost, large yield, simple operation, and environmental protection. This review summarizes the advances in engineering microbial cell factories to produce L-LA. First, the synthetic pathways and microorganisms for L-LA production are outlined. Then, the metabolic engineering strategies for constructing cell factories to overproduce L-LA are summarized and fermentation modes for L-LA production are also given. Finally, the challenges and prospects of the microbial production of L-LA are discussed. This review provides theoretical guidance for researchers engaged in L-LA production.

Synthesis, Crystal Growth, and Annealing of CdSxSe1-x and Cr:CdS0.8Se0.2 Single Crystals.

Mid-infrared laser in the 2-5 μm wavelength region is in the atmospheric transmission window range, and hence, it has important application prospects in the fields of optoelectronic countermeasures, space communication, environmental remote sensing, and molecular spectroscopy. One of the most promising technological approaches to achieve mid-infrared laser output is based on direct lasing of transition-metal (TM)-doped II-VI chalcogenide crystals. In this work, CdSxSe1-x and Cr:CdS0.8Se0.2 polycrystals were synthesized by a chemical vapor synthesis method from a stoichiometric mixture of vacuum-sublimed CdS and CdSe. The structure of the synthesized products was analyzed by X-ray diffraction (XRD). Using these synthesized products, CdSxSe1-x and Cr:CdS0.8Se0.2 single crystals were grown by the physical vapor transport (PVT) method. After annealing, the band gap becomes smaller and the transmission range widens to 17 μm. The composition of the single crystals was determined by energy-dispersive spectrometry (EDS) mapping and XPS, and it was found to be uniform throughout the ingot. In addition, the absorption peak maximum for the Cr2+ ion in the Cr:CdS0.8Se0.2 crystal is at 1.84 μm.

SILVER AND CERIUM NANOPARTICLES SYNTHESIS METHODS

The study of nanoparticles is currently an area of intense scientific interest due to a wide range of application possibilities in medical and biological fields. Therefore, national initiatives in the field of nanotechnology and nanoparticle research receive broad government support in many countries of the world. Nanoparticle synthesis methods are simple and can be carried out without special laboratory equipment. The very fact of the simplicity of the synthesis process from the technical side makes the synthesis and use of nanoparticles in medicine, biotechnology and other fields of human activity extremely attractive. Silver nanoparticles have a pronounced antibacterial effect against a wide range of bacterial pathogens. The antioxidant properties of cerium nanoparticles are described, which provide the prospect of their use in the therapy of tumor and viral diseases. That is why the purpose of the work is to analyze and compare possible methods of synthesis of silver and cerium nanoparticles and to single out the most promising method. The analysis of the known methods of synthesis of silver and cerium nanoparticles, as well as a comparison of their advantages and disadvantages, allowed us to conclude that the biological synthesis of nanoparticles is the most promising, in particular with the use of plant extracts. An important feature of the biological method of synthesis of nanoparticles is the absence of toxic reducing agents and the complex multi-stage process in comparison with the chemical method of synthesis. Moreover, the biological method of synthesis allows obtaining nanoparticles of a certain size and shape in a wide range of values, while the physical method is very limited. Regulation of the size and shape of nanoparticles obtained by biological synthesis is provided by a simple change of the synthesis conditions, namely the pH value, acidity, concentration of the corresponding metal salt, etc. Green synthesis is a safe ecological and cost-effective method of synthesis of silver and cerium nanoparticles.

Methods of Chemical Synthesis in the Synthesis of Nanomaterial and Nanoparticles by the Chemical Deposition Method: A Review

Methods of Chemical Synthesis in the Synthesis of Nanomaterial and Nanoparticles by the Chemical Deposition Method: A Review

An Efficient Gram-Scale Chemical Synthesis of Purine Locked Nucleic Acid Nucleoside-5'-O-Triphosphates.

This article presents a simple, reliable, straight-forward, general, and efficient chemical method for the gram-scale synthesis of purine locked nucleic acid (LNA) nucleotides, such as LNA guanosine-5'-O-triphosphate (LNA-GTP) and LNA adenosine-5'-O-triphosphate (LNA-ATP), starting from the corresponding nucleoside. The reaction pathway employs an improved protection-free "one-pot, three-step" Ludwig synthetic strategy. The first step involves monophosphorylation of nucleoside with phosphorus oxychloride followed by reaction with tributylammonium pyrophosphate and subsequent hydrolysis of the resulting cyclic intermediate to furnish the corresponding LNA nucleotide in good yields. It is noteworthy that the reaction affords high-purity (>99.5%) LNA nucleotide after diethylaminoethyl Sepharose column purification. © 2022 Wiley Periodicals LLC. Basic Protocol: Synthesis of LNA nucleoside-5'-O-triphosphates.