Rapid Chemical Method Research Articles

A rapid chemical method for production of xylitol from D-xylose as a renewable feedstock from spent aromatic waste

Xylitol is occurring naturally as a minor constituent in many fruits and vegetables. Commercially, xylitol is produced by chemical methods from D-xylose for application as an alternative sweetener in food and pharmaceutical products. Although biomass-derived xylose can be used as a potential substrate for xylitol production, its prerequisite purification before a catalytic hydrogenation directly impacts the production cost. In addition, the isolation of xylose falls under a routine pretreatment activity during conversion of biomass to platform chemicals. The resulting hydrolysate often exhibits a low concentration of xylose and other monosaccharides. Concentrating the hydrolysate to a desired level for conversion to xylitol under chemical/biological methods increases the expenditure cost. Many times, concentration by heating may cause the degradation of contained sugars in the hydrolysate. Therefore, this study has been carried out to obtain a mixture of C5/6 sugars, predominantly the D-xylose in a solid dry form (∼10 % yield, >98 % purity) directly from acid hydrolysate of spent aromatic waste. Biomass-derived D-xylose was further transformed to xylitol (100 % conversion) by a fast (10 min), efficient, and solvent-free chemical approach using a modified sodium borohydride (NaBH4) catalyst on a wet silica (SiO2) support at RT. All reagents and solvents used in the process were recovered and recycled, leading to the minimal waste generation.

One-pot Low-Temperature Synthesis of High Crystalline Cu Nanoparticles

This research work has developed a classic method to synthesize high crystalline ~50nm copper (Cu) nanoparticles at a low temperature of 80oC. While nanoparticle synthesis is a concern, a rapid chemical reduction method (CRM) was introduced by reducing copper salts and an appropriate capping agent. The capping agent facilities controlled the movement and formation of nanoparticles that were further investigated by X-ray Diffraction (XRD), Thermo-gravimetric Analysis (TGA), Transmission Electron Microscope (TEM), and Selected Area Electron Diffraction (SAED) as well as TEM couple EDS. The such in-depth analysis demonstrates a 100% crystalline phase with having to predominate (111), (200), and (220) planes and 84% purity. The medium and process protocol selection may be adapted to synthesize other nanoparticles for different functional applications.

Strong Electronic Interaction between Amorphous MnO2 Nanosheets and Ultrafine Pd Nanoparticles toward Enhanced Oxygen Reduction and Ethylene Glycol Oxidation Reactions

AbstractStrengthening the interface interaction between metal and support is an efficient strategy to improve the intrinsic activity and reduce the amount of noble metal. Amorphization of support is an effective approach for enhancing the metal‐support interaction due to the numerous surface defects in amorphous structure. In this work, a Pd/a‐MnO2 electrocatalyst containing ultrafine and well‐dispersive Pd nanoparticles and amorphous MnO2 nanosheets is successfully synthesized via a simple and rapid wet chemical method. Differing from the crystal counterpart (Pd/c‐MnO2), the flexible structure of amorphous support can be more favorable to electron transfer and further enhance the metal‐support interaction. The synergism between Pd and amorphous MnO2 results in the downshift of the d‐band center, which is beneficial for the desorption of critical intermediates both in oxygen reduction reaction (ORR) and in ethylene glycol oxidation (EGOR). Due to the lower *.OH desorption energy of Pd/a‐MnO2 surface, the rapid dissociation of *OH from Pd facilitates the formation of H2O in ORR, thus demonstrating superior ORR performance comparable to Pt/C. For EGOR, the presence of amorphous MnO2 promotes the formation of adsorbed OH species, which accelerates the desorption of intermediate CO from Pd sites, and thus exhibits excellent EGOR activity and stability.

Porous graphitic carbon nitrides integrated biosensor for sensitive detection of cardiac troponin I

Early diagnosis of cardiovascular diseases (CVDs) has the potential to save millions of lives each year. Sensitive quantitative measurement of blood cardiac troponin I (cTnI) is required for early diagnosis of CVDs. Porous graphitic carbon nitride (PCN) nanomaterials integrated biosensor that detects picogram/mL concentrations of cTnI is reported. PCN is an updated version of graphitic carbon nitride (GCN) with improved porosity and electronic structure. A rapid two-step chemical method was described to synthesize PCN and gold nanoparticles functionalized PCN (PCN-AuNPs). The modification of the electrode surface with PCN materials had a significant impact on the electrochemically active surface area (EASA), interfacial electron transport, aptamer immobilization, and biosensing performance. The use of PCN nanomaterial in cTnI aptasensing resulted in a 3.2-fold increase in signal amplification. PCN-AuNPs found practically applicable in human blood serum (cTnI-spiked). Furthermore, a low-cost and user-friendly sensing platform has been demonstrated by integrating a PCN-AuNPs aptasensor, a custom-made miniaturized potentiostat, and a smartphone, which provided rapid, sensitive point-of-care (PoC) analysis of cTnI. Highly sensitive detection limit (0.01 pg/mL), rapid analysis time (2 min), and small sample volume (20 μL) are the other advantages of this nano-biosensor.

Kinetics and Mechanisms of Cr(VI) Removal by nZVI: Influencing Parameters and Modification

In this study, single-spherical nanoscale zero valent iron (nZVI) particles with large specific sur-face area were successfully synthesized by a simple and rapid chemical reduction method. The XRD spectra and SEM–EDS images showed that the synthesized nZVI had excellent crystal struc-ture, but oxidation products, such as γ-Fe2O3 and Fe3O4, were formed on the surface of the parti-cles. The effect of different factors on the removal of Cr(VI) by nZVI were studied, and the opti-mum experimental conditions were found. Kinetic and thermodynamic equations at different temperatures showed that the removal of Cr(VI) by nZVI was a single-layer chemical adsorption, conforming to pseudo-second-order kinetics. By applying the intraparticle diffusion model, the ad-sorption process was composed of three stages, namely rapid diffusion, chemical reduction, and in-ternal saturation. Mechanism analysis demonstrated that the removal of Cr(VI) by nZVI in-volved adsorption, reduction, precipitation and coprecipitation. Meanwhile, Cr(VI) was reduced to Cr(III) by nZVI, while FeCr2O4, CrxFe1−xOOH, and CrxFe1−x(OH)3 were formed as end products. In addition, the study found that ascorbic acid, starch, and Cu modified nZVI can promote the removal efficiency of Cr(VI) in varying degrees due to the enhanced mobility of the particles. These results can provide new insights into the removal mechanisms of Cr(VI) by nZVI.

Bio-Based Synthesis of Silver Nanoparticles from Waste Agricultural Biomass and Its Antimicrobial Activity

The problem of cleaning and disinfecting surfaces has become extremely important in the context of the ongoing SARS-CoV-2 coronavirus pandemic. However, it should be considered that, in everyday life, we come into contact with many other viruses, as well as pathogenic bacteria and fungi, that may cause infections and diseases. Hence, there is a continuous need to search for new and more effective methods of fighting pathogens. Due to their documented antimicrobial activity, silver nanoparticles may be an interesting alternative to the commonly used surface cleaners and disinfectants. Therefore, the present study aimed to evaluate the bactericidal properties of silver nanoparticles obtained with the use of nontoxic plant waste biomass against bacteria isolated from the environment. Silver nanoparticles with the desired physicochemical characteristics were obtained by a simple and rapid chemical reduction method using plant waste such as unused parsley stems and potato peels (the biogenic method). A nanosilver colloid was also prepared by the chemical reduction method, but with reducing and stabilizing chemical substances (the chemical method) used as a control. The bacterial susceptibility to nanosilver synthesized using both methods was evaluated using the disk-diffusion method. The sensitivity of particular Escherichia coli and Staphylococcus aureus isolates to nanosilver varied considerably, and the strongest antimicrobial effect was found in the case of nanoparticles synthesized by the chemical method using a strong chemical reducing agent and a polymeric stabilizing substance, while nanosilver obtained using the biogenic method, using phytochemicals, also had a strong antimicrobial effect, which was found to be extremely satisfactory. Thus, it can be strongly concluded that the biogenic, pro-ecological method of synthesis with the use of plant waste biomass presented in this work allows the application of biogenic nanosilver as a component of agents for washing and disinfection of public utility surfaces.

Carbon dots with tunable emission based on pH values

Fluorescent carbon dots are the hot topic of fluorescent nanomaterials due to their outstanding optical properties and promising practical application. However, the drawback of fluorescent carbon dots that their strong emission frequently in the blue-light region restricts their further applications. Here, fluorescent carbon dots with tunable emission were synthesized through a simple, rapid and low-cost chemical thermal treatment method. The fluorescent carbon dots emit bright green, yellow and orange fluorescence with different pH value. This is due to the combined effect of size and surface states of fluorescent carbon dots. Further studies show that the fluorescent carbon dots possess intrinsic horseradish peroxidase-like activity and were successfully applied to directly detect Cr3+.

Synthesis of a functionalized carbon supported platinum–iridium nanoparticle catalyst by the rapid chemical reduction method for the anodic reaction of direct methanol fuel cells

Direct methanol fuel cells (DMFCs) stand out among the most common technologies in energy storage and are environmentally friendly energy converters that convert chemical energy into electrical energy.

ERα-Targeting PROTAC as a Chemical Knockdown Tool to Investigate the Estrogen Receptor Function in Rat Menopausal Arthritis.

Proteolytic targeting chimeras (PROTACs) is a rapid and reversible chemical knockout method. Compared with traditional gene-editing tools, it can avoid potential genetic compensation, misunderstandings caused by spontaneous mutations, or gene knockouts that lead to embryonic death. To study the role of estrogen receptor alpha (ERα) in the occurrence and progression of menopausal arthritis, we report a chemical knockout strategy in which stable peptide-based (PROTACs) against ERα to inhibit their function. This chemical knockdown strategy can effectively and quickly inhibit ERα protein in vivo and in vitro. In the rat menopausal arthritis model, this study showed that inhibiting estrogen function by degrading ERα can significantly interfere with cartilage matrix metabolism and cause menopausal arthritis by up-regulating matrix metalloproteinase (MMP-13). The results of this study indicate that ERα is a crucial estrogen receptor for maintaining cartilage metabolism. Inhibition of ERα function by PROTACs can promote the progression of osteoarthritis.

Abstract 20: HiBiT tagging system for high throughput chemical screening for chemotherapy

Abstract Chemical screening is an essential procedure for finding novel drugs of cancer treatments. Especially, cell-based screenings are mostly used for discovery of novel compounds or drug repositioning of already-used drugs. Cell viability or cell proliferation are usually used for evaluation of effects of candidate novel compounds for cancer treatments. However, high throughput system for rapid evaluation of endogenous target protein expression changes has not been established so far. Therefore, an easy and quick method for detection of endogenous target protein expression changes has been strongly needed for drug discovery. Herein, we established a novel chemical compound screening system using the HiBiT-tagging system for this aim using PD-L1 as an example. HiBiT tag is a small peptide tag composed of only 11 amino acids forming a dimer with LgBiT, and functions as a Nanoluciferase. The shortness of the peptide tag is useful for insertion of tag using genome editing technology. Thereby, we established a rapid chemical screening method using HiBiT-tagged cell lines created by CRISPR-Cas9 system. With this method, we made it possible to detect endogenous target protein expression changes within 10 minutes by just adding lytic buffer and LgBiT. For validation of this method, we performed chemical screening of PD-L1 using a HiBiT-tagged lung adenocarcinoma cell line with 1,280 compounds. As a result, we identified microtubule inhibitors as compounds upregulating PD-L1, and validated its upregulation of PD-L1 with qPCR and western blotting. In conclusion, we succeeded in establishing the method for chemical compounds detecting endogenous target protein expression changes with HiBiT-tagging system. Furthermore, we validated this method by performing chemical screening with PD-L1, and succeeded in identifying microtubules inhibitors as up-regulators of PD-L1. Citation Format: Yutaro Uchida, Takahide Matsushima, Ryota Kurimoto, Tomoki Chiba, Yuki Inutani, Hiroshi Asahara. HiBiT tagging system for high throughput chemical screening for chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 20.

Investigation on antibacterial and hemolytic properties of magnesium-doped hydroxyapatite nanocomposite

In this work, we have investigated the antibacterial and hemolytic efficacy of hydroxyapatite (HA) and Magnesium (Mg) incorporated hydroxyapatite (MHA), where the composite was synthesized by a rapid and cost-effective microwave-assisted wet chemical method. The synthesized MHA composite was characterized by using X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), High-resolution transmission electron microscopy (HRTEM), in vitro antibacterial and anti-inflammatory activities. Also, the hemolytic activity of the sample was studied using the spectrophotometer technique. From the analysis, the XRD diffractogram confirms the presence of HA and MHA by the JCPDS card no: 09-0432. The chemical bonding confirmed the presence of Mg and HA in the nanocomposite and the HRTEM confirmed the spherical shape morphology of synthesized samples. The in vitro antibacterial activity of the nanocomposite was studied against the gram-positive bacteria Staphylococcus aureus and gram-negative bacteria Escherichia coli. Also, the in vitro anti-inflammatory activity of the sample was studied against the standard drug Diclofenac sodium and found to be compatible with the standard values. Further, the samples are investigated to be non-hemolytic according to the ASTM F756-00 (American Society for Testing and Materials Designation). Based on the studies, the prepared Mg-HA nanocomposite can be potential for the biomedical applications of dental, orthopaedic, and stem cell research.

Investigation on dielectric properties of iron oxide nanoparticles-embedded binary transition metals-doped polyaniline-metal hybrid nanocomposites

Dielectric material based on hybrid PANI-metal nanocomposites always gained an immense research interest due to its unique properties. Herein, we have synthesized iron oxide nanoparticles embedded two different binary transition metal doped PANI nanocomposites via simple in situ rapid mixing chemical oxidative polymerization method. Morphological, structural, electronic and chemical composition of the composites were systematically studied. The influence of dopant concentration in tuning PANI surface from flake like to spherical bead like morphology was analysed by high resolution transmission electron microscopy. Moreover, dielectric parameters as function of frequency have been investigated at room temperature in a frequency range 100Hz–2MHz and the result showed that the as prepared flake like nanocomposites - 0.3 M Cu-Fe-PANI and 0.7 M Mn-Fe-PANI systems are promising dielectric materials.

High-performance supercapacitor electrode and photocatalytic dye degradation of mixed-phase WO3 nanoplates

We report a single-step synthesis of mixed-phase WO3 nanoplates by a rapid and cost-effective wet chemical method. The excellent electrochemical performance of WO3 nanoplate attributed to the proton insertion supported pseudocapacitive charge storage with a superior specific capacitance of 471 Fg−1 and greater stability. Additionally, the WO3 nanoplate shows better methylene blue (MB) dye degrading performance of 87% in 105 min. Thus the bi-functional activity of the WO3 nanoplates has the potential to employ in the integrated devices for further applications.

Tuning morphological and dielectric performance of a hybrid PANI-metal nanocomposite using p-TSA/binary transition metal compounds

Ternary doped polyaniline hybrid composites were synthesized by rapid mixing chemical oxidative polymerization method using FeCl3 oxidant-dopant along with different concentrations of CuSO4/MnSO4, a second transition metal dopant in combination with an organic acid p-TSA. The stochiometric proportion of dopants used in the synthesis plays a critical role in modifying PANI's physical and chemical properties. The contribution of ternary dopants in modifying PANI morphology from whisker like surface to flaky morphology and frequency dependent dielectric properties of the as prepared PANI composites were systematically analyzed.

A simple method for the precise determination of multi-elements in pyrite and magnetite by ICP-MS and ICP-OES with matrix removal

A simple, economical, and rapid chemical method was developed for the precise measurement of major and trace elements in bulk pyrite and magnetite. This method, which required only 10–20 mg of sample, used inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) with a polyurethane foam (PUF)-based matrix removal step. Interference derived from the iron-rich mineral matrix was reduced by the removal of iron from the sample solution using 0.18 g PUF in 6 M HCl. The extraction conditions (e.g., temperature, shaking time, and initial iron concentration) were intensively investigated to achieve high iron separation efficiency. An iron removal rate of 92.7 ± 0.7% (n = 3, SD) and recoveries of 97–103% for 17 trace elements were obtained under the optimized separation conditions. To evaluate the feasibility of our method, reference materials for pyrite (GBW07267) and iron formation (FER-1 and FER-2) were analyzed. Our results were consistent with the certified values or literature values, and the precision was comparable to the certified uncertainty or that of previous methods in which 100 mg of sample powder was digested. These results confirmed that this novel method is an efficient technique for the precise measurement of multi-elements in pyrite and magnetite. Relative to other methods, our protocol has great potential for analyzing a wide variety of trace elements in small amounts (<10 mg) of iron-rich samples with applicability in geochemistry, cosmochemistry, and environmental studies.

Precise size and dominant-facet control of ultra-small Pt nanoparticles for efficient ethylene glycol, methanol and ethanol oxidation electrocatalysts

Control of the structure and shape of platinum nanocrystals has recently attracted much attention, mostly due to their specific properties and related catalytic functionalities. However, the realization of platinum nanocrystals with controlled sizes and dominant facet types remains a significant challenge. In this study, platinum nanoparticles with controllable sizes and dominant facets are produced via a simple, organic agent-free, rapid, clean and direct chemical reduction method. The effects of initial solution pH on the sizes and dominant facets of the platinum nanoparticles are investigated and the mechanism for different sizes and facets are examined. Electrocatalytic analyses show that the catalytic activities and stabilities of the synthesized platinum nanoparticles are related to their sizes and dominant facets, and these nanoparticles display great potential as substitutes for commercial Pt/C in the effective catalysis of ethylene glycol, methanol, and ethanol electrooxidation in alkaline medium. Among the present platinum nanoparticles, the nanoparticles synthesized in pH 3 initial conditions, with small average size and (111)-dominant facets, display the best electrocatalytic activity and stability.

Food quality evaluation of accelerated shelf life of chili sauce using Fourier transform infrared spectroscopy and chemometrics

Recently, spectroscopy analysis has been used as a rapid chemical analysis method of food products. To evaluate the potentiality of Infrared spectroscopy (IR) in food analysis during storage, an accelerated shelf-life study was carried out on three types of chili habanero sauces at 50°C for a period of 24 days. Only some physicochemical and sensory evaluation showed changes during chili sauces storage. FT-IR spectra tandem with principal component analysis (PCA) allow differentiating between a fresh sauce and a long-time prepared one. Partial least squares model showed that FT-IR data can be compared to some physicochemical and sensorial parameters. Results of sensorial and spectrophotometry analyses can be used to calculate the shelf life of the sauces. This is the first study that reported about the use of a rapid and low-cost method of FT-IR tandem chemometrics as the food quality evaluation of accelerated shelf life of a chili sauces-based vegetable ingredients. Practical applications Food processing requires faster, more efficient, and easier to use tools to evaluate the quality of its ingredients, the monitoring of the process, and the quality of the final product, as well as methods to monitor the freshness of the products during storage. This study suggests that the infrared spectroscopy together with the chemometric analysis could be a viable and fast alternative, which is given in a single step to cover the needs of quality monitoring of products both in the development of new products and in the process in the food industry.

Effect of Mn2+ as a redox additive on ternary doped polyaniline-metal nanocomposite: an efficient dielectric material

An efficient ternary doped polyaniline-metal nanocomposite was synthesized via in situ rapid mixing chemical oxidative polymerization method. The detailed morphological and structural analysis shows the incorporation of binary transition metals (Fe & Mn) in a highly crystalline PANI matrix with a modified flaky morphology. Further dielectric and electrochemical characterizations substantiate a high dielectric constant and specific capacitance of about 613F/g with a good cyclic stability for the as synthesized PANI material.

Simultaneously Enhanced Efficiency and Stability of Perovskite Solar Cells with TiO2@CdS Core–Shell Nanorods Electron Transport Layer

AbstractBoth demands of stability and efficiency constitute the gargantuan barriers of perovskite solar cells (PSCs), hampering the academic communities and industrial production. Herein, it is demonstrated that, after depositing optimized CdS shell layers on TiO2 nanorod arrays (NAs) by a simple and rapid chemical bath method at room temperature, the efficiency and stability of PSCs are simultaneously enhanced. The PSCs based on TiO2/CdS core–shell NAs achieve higher power conversion efficiency up to 17.71%, compared to 15.93% of the pristine TiO2 NAs‐based cells. Especially, the stability of the PSCs is prominently improved after optimized CdS layer modification without encapsulation. The significant enhancement of both efficiency and stability are mainly ascribed to that the type‐II structure of TiO2/CdS coaxial nanorods can suppress recombination, and the oxygen vacancies on TiO2 surfaces are not directly contacted with perovskite layers. The surface modification on TiO2 NAs opens up an alternative approach toward improving the performance and stability of PSCs.

A facile synthesis and optoelectronic characterization of Znq2 and Alq3 nano-complexes

We prepared two organo-metallic nano-complexes zinc bis(8-hydroxyquinoline)(Znq2) and aluminum tris(8-hydroxyquinoline)(Alq3), and utilized these materials as fluorescent part in organic light-emitting diodes (OLEDs). The nano-complexes were synthesized via a facile and rapid chemical method and were characterized by scanning electron microscopy, X-ray diffraction, ultraviolet–visible, Fourier transform infrared spectroscopy, and Photoluminescence spectroscopy. The energy levels of Zn and Al complexes were determined by cyclic voltammetry measurements. Further structural elucidation was carried out using FT-IR in which the stretching frequencies of the Znq2 and Alq3 bonds were determined. Green photoluminescence with maximums at 565 and 524 nm was observed from the Znq2 and Alq3 powders, respectively. In comparison to Alq3 complex the photoluminescence intensity of Znq2 complex is less. In this work, we also investigate electrical and optical performance of the organic light-emitting diodes with both zinc and aluminum complexes as emissive materials. For this purpose we prepared four sets of samples. We configured the samples into two structures: (A) indium tin oxide(ITO)/poly(3,4-ethylenedi-oxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/polyvinylcarbazole(PVK)/Alq3 or Znq2/(2-4-biphenylyl)-5-phenyl-oxadiazole(PBD)/aluminum(Al) and at the second structure (B) ITO/PEDOT:PSS/PVK: Alq3 or Znq2: PBD/Al was prepared. Hole transport layer (HTL), electron transport layer (ETL), and emissive layers were deposited by the spin-coating method, and cathode layer (Al) was also deposited by the thermal evaporation method. Our results show that the electrical efficiency of zinc complex-based devices is much better than Alq3-based devices.