Search Results (91)

Date pits are considered waste, and micronized date pit powder could be developed for use in foods and bio-products. In this study, micronized date pit powders were extracted by alcoholic sedimentation after ultrasound treatment. The control was considered untreated, i.e., without sonication. Six micronized fractions (i.e., three from control and three from treated) were prepared by three stages of alcoholic sedimentation. In the case of untreated date pit powder, the average particle size of the fractionated date pit powder (i.e., residue) from three stages of alcoholic sedimentation varied from 89 to 164 µm, while ultrasonic treatment showed variation from 39 to 65 µm. The average particle size of the supernatant fractions of untreated date pit powder varied from 22 to 63 µm, while ultrasonic treatment showed variation from 18 to 44 µm. Ultrasound treatment produced smaller particles. In all cases, Scanning Electron Microscopy (SEM) showed that supernatant fractions contained lumped particles compared to the residue fractions. Transmission Electron Microscopy (TEM) showed the presence of nanoparticles in all extracted fractions. Two glass transitions were observed in all fractions except for the residue from the first sedimentation stage. In addition, higher levels of degradation in the fractionated date pits could be achieved by ultrasonic treatment, as is evident from the Fourier Transform Infrared (FTIR) analysis. Full article

Colorectal cancer (CRC) remains a major global health challenge, necessitating the development of more effective and environmentally sustainable treatments. This study presents a novel green synthetic protocol for 1,3,5-triazine derivatives with anticancer potential, employing both microwave-assisted and ultrasound-assisted methods. The synthesis was optimized using 4-chloro-N-(2-chlorophenyl)-6-(morpholin-4-yl)-1,3,5-triazin-2-amine as the key intermediate, with sodium carbonate, TBAB, and DMF providing optimal yields under microwave conditions. To enhance sustainability, a modified sonochemical method was also developed, enabling efficient synthesis in aqueous media with a minimal use of organic solvents. A series of nine morpholine-functionalized derivatives were synthesized and evaluated for cytotoxic activity against SW480 and SW620 colorectal cancer cell lines. Compound 11 demonstrated superior antiproliferative activity (IC₅₀ = 5.85 µM) compared to the reference drug 5-fluorouracil, while compound 5 showed promising dual-line activity. In silico ADME analysis supported the drug likeness of the synthesized compounds, and biomimetic chromatography analysis confirmed favorable physicochemical properties, including lipophilicity and membrane affinity. These results underscore the potential of the developed protocol to produce bioactive triazine derivatives through an efficient, scalable, and environmentally friendly process, offering a valuable strategy for future anticancer drug development. Full article

A sonochemical synthesis of SnS₂ quantum dots using acetone as a solvent is investigated. Two different tin sources (SnCl₂∙2H₂O or SnCl₄∙5H₂O) as well as two different sulfur sources (thioacetamide or Na₂S₂O₃) were applied. The sonication time was also varied between 60 and 120 min. Resulting products of syntheses were characterized with the following techniques: powder X-ray diffraction, electron microscopy (SEM and HR-TEM), Raman and FT-IR spectroscopies, the Tauc method, and X-ray photoelectron spectroscopy. Obtained SnS₂ nanostructures were in the form of quantum dots in the case of synthesis lasting 60 min (size of crystallites in the range of 3.5–7 nm) and in the form of elongated nanorods of length ca. 25–30 nm and width of 5–6 nm in the case of synthesis lasting 120 min. XPS analyses revealed that the surface of the obtained products contained a significant amount of tin at the second oxidation state (i.e., SnS). The quantum dots produced in the synthesis lasting 60 min showed a value of energy bandgap of 2.7 eV indicating potential applications in photocatalysis. Full article

Sonochemical synthesis is becoming a popular method of preparing various nanomaterials, including metals, carbons, oxides, and chalcogenides. This method is relatively cheap and responds to the challenges of green chemistry as it typically does not involve high temperatures, high pressures, inert atmospheres, or long reaction times in comparison to other conventional methods. The utilization of ultrasound in synthesis makes the elimination of toxic solvents possible, as well as the execution of the synthesis without the use of reducing and stabilizing agents, while receiving products with the same or even better properties. The application of ultrasound allows for the synthesis of various nanomaterials with different properties for use in fields such as catalysis, electrochemistry, medicine, and biosensors. The final product is influenced by multiple variables such as temperature, pH, reagents, capping agents, time of reaction, and the addition of dopants. Full article

The serotonin 5-HT₆ receptor (5-HT₆R), expressed almost exclusively in the brain, affects the Cdk5 signaling as well as the mTOR pathway. Due to the association of 5-HT₆R signaling with pathways involved in cancer progression, we decided to check the usefulness of 5-HT₆R ligands in the treatment of CNS tumors. For this purpose, a new group of low-base 5-HT₆R ligands was developed, belonging to arylsulfonamide derivatives of cyclic arylguanidines. The selected group of molecules was also tested for their antiproliferative activity on astrocytoma (1321N1) and glioblastoma (U87MG, LN-229, U-251) cell lines. Some of the molecules were subjected to ADMET tests in vitro, including lipophilicity, drug binding to plasma proteins, affinity for phospholipids, drug–drug interaction (DDI), the penetration of the membrane (PAMPA), metabolic stability, and hepatotoxicity as well as in vivo cardiotoxicity in the Danio rerio model. Two antagonists with an affinity constant K_i < 50 nM (PR 68 K_i = 37 nM) were selected. These compounds were characterized by very high selectivity. An analysis of pharmacokinetic parameters for the lead compound PR 68 confirmed favorable properties for administration, including passive diffusion and acceptable metabolic stability (metabolized in 49%, MLMs). The compound did not exhibit the potential for drug–drug interactions. Full article

Plastics have become indispensable in modern society; however, the proliferation of their waste has become a problem that can no longer be ignored as most plastics are not biodegradable. Depolymerization/degradation through sustainable processes in the context of the circular economy are urgent issues. The presence of multiple types of plastic materials makes it necessary to study the specific characteristics of each material. This mini-review aims to provide an overview of technological approaches and their performance for the depolymerization and/or degradation of one of the most widespread plastic materials, polypropylene (PP). The state of the art is presented, describing the most relevant technologies focusing on advanced oxidation technologies (AOT) and the results obtained so far for some of the approaches, such as ozonation, sonochemistry, or photocatalysis, with the final aim of making more sustainable the PP depolymerization/degradation process. Full article

Cellulose is used widely in antimicrobial packaging due to its abundance in nature, biodegradability, renewability, non-toxicity, and low cost. However, how efficiently and rapidly it imparts high antimicrobial activity to cellulose-based packaging materials remains a challenge. In this work, Ag NPs were deposited on the surface of carboxymethyl cellulose/starch/N’N Methylenebisacrylamide film using ultrasonic radiation. Morphology and structure analysis of as-prepared films were conducted, and the antibacterial effects under different ultrasonic times and reductant contents were investigated. These results showed that Ag NPs were distributed uniformly on the film surface under an ultrasonic time of 45 min. The size of Ag NPs changes as the reducing agent content decreases. The composite film demonstrated a slightly better antibacterial effect against E. coli than against S. aureus. Therefore, this work can provide valuable insights for the research on antimicrobial packaging. Full article

The production of low-dimensional materials is the key topic of nanoscience. The development of new routes to downsize organic and inorganic materials has focused the attention of a great part of the scientific community that is still debating on the best route to pursue. Among nanostructures, 2D species have been investigated since the discovery of graphene. Nonetheless, the production of 2D materials is very complex, and the discussion on which is the most profitable way is still open. Ultrasound-assisted techniques represent one of the best routes for the production of 2D materials with minimum consumption of energy and best performances. Accordingly, we present a concise and exhaustive discussion about the use of ultrasound-assisted techniques for the production of both organic and inorganic 2D materials, also providing a theoretical overview of the mechanism behind the use of ultrasounds in synthetic material science. Full article

Indium nitride is an excellent semiconductor that belongs to the group of III nitride materials. Due to its unique properties, it is applied to various optoelectronic applications. However, its low thermal stability makes it difficult to synthesize. The present study introduces the synthesis of indium nitride nanoparticles, using ultrasound power (sonochemistry). The sonochemical method provides a low-cost and rapid technique for nanomaterial synthesis. InN nanoparticles were produced in only 3 h through the sonochemical reaction of InCl₃ and LiN₃. Xylene was used as a reaction solvent. X-ray powder diffraction (XRD) as well as high-resolution transmission electron microscopy (HRTEM) were adopted for the characterization of the obtained powder. According to our results, ultrasound contributed to the synthesis of InN nanocrystals in a cubic and a hexagonal phase. The obtained InN nanoparticles were further used to decorate titanium dioxide (TiO₂) by means of ultrasound. The contribution of InN nanoparticles on the processes of photocatalysis was investigated through the degradation of methylene blue (MB), a typical organic substance acting in place of an environment pollutant. According to the obtained results, InN nanoparticles improved the photocatalytic activity of TiO₂ by 41.8% compared with commercial micrometric titania. Full article

Film applications’ recent advances in the alimentary industry mainly focus on extending product shelf life. Researchers have investigated the use of nanomaterials as active packaging to shield food product contents from the outside elements and prevent bacterial development. In this context, the use of sonochemistry energy offers a friendly and efficient opportunity to obtain this kind of film. However, access to an ultrasonic homogenizer is limited because of the cost and accessories. In this work, a self-cleaning coating based on the SiO₂-TiO₂-PDMS composite was obtained by the sol–gel method coupled with indirect sonochemical energy. Two sonication reaction times were used to investigate its impact on the final composite’s chemical, morphological, and antibacterial properties. TEM and SEM techniques indicate an amorphous morphology and superficial cracks in SiO₂-TiO₂-PDMS films over aluminum foil. At the same time, AFM reveals a rise in rugosity with a value of Ra = 18.7 ± 2.47 nm, increasing the sonochemical reaction time. Non-significative changes by FTIR-ATR analysis were observed. The antibacterial evaluation was conducted, and the results indicate that both composites exhibited superior effectiveness. Specifically, the S40 film demonstrated a significant reduction in the growth of Gram-negative cells (E. coli, P. putida, and P. aeruginosa), with reductions ranging from 50% to 95%. In contrast, the reduction in Gram-positive cells (S. aureus) was less than 10%. These findings underscore the potential application of the SiO₂-TiO₂-PDMS film as active packaging. Full article

Currently, in the context of biorefinery and bioeconomy, lignocellulosic biomass is increasingly used to produce biofuels, biochemicals and other value-added products. Microwaves and ultrasound are emerging techniques that enable efficient and environmentally sustainable routes in the transformation of lignocellulosic biomass. This review presents some of the most important works published in the last few years on the application of microwaves and/or ultrasound in lignocellulosic materials pretreatment and can be used as a starting point for research into this theme. This review is divided into four parts. In Part I, the theoretical fundamentals of microwave and ultrasound treatments are reviewed. Dielectric constants for biomass, factors that influence pretreatment, are some of the subjects addressed. In Part II, the effects that these techniques have on lignocellulosic biomass (on the size and surface area of the particle; on the content of lignin, hemicellulose and cellulose; on the crystallinity index of cellulose; on the effect of solubilization of organic matter; on hydrolysis and reduction of sugars) are discussed. In Part III, emphasis is given to the contribution of microwaves and ultrasound in obtaining value-added products. In this context, several examples of liquefaction and extraction procedures are presented. Part IV describes examples of performing sonocatalysis on lignocellulosic biomass to obtain value-added products, such as furfural, whose production is significantly reduced by ultrasound treatment. Full article

As the most mature natural gas sweetening process, absorption has always been improved to meet the separation requirement. Recently, ultrasonic irradiation has been proposed as a technique that can intensify CO₂ absorption. However, further studies are still required, particularly focusing on the sonochemical effect. Since the influence of the sonochemical effect on the reaction pathway is still debatable, attention must be given to verifying the influence of ultrasonic irradiation on the chemical reactions of CO₂ absorption. Hence, this work aims to evaluate the influence of $\dot{\mathrm{O}\mathrm{H}}$ radicals generated by the sonochemical effect on the chemical reactions involved during CO₂ absorption using promoter-free methyldiethanolamine (MDEA). For the evaluation, various samples under irradiated and non-irradiated conditions are analyzed using the HPLC characterization technique. The results show that the hypothesis of changing the reaction pathway due to the presence of the sonochemical effect is invalid. However, it can accelerate the generation of hydroxyl radicals ($\dot{\mathrm{O}\mathrm{H}}$) via water sonolysis. Thus, the origin of sonochemistry in aqueous solutions is defined as water sonolysis. The analysis of the CO₂ absorption rate also demonstrates the presence of accelerated chemical reactions (contributed by the $\dot{\mathrm{O}\mathrm{H}}$ radicals), which could potentially make the slow kinetic MDEA more practical for industrial application. Full article

The present work is based on a mathematical model describing a single acoustic cavitation bubble oscillating under an ultrasonic field of 200 and 300 kHz and an acoustic amplitude of 1.8 atm within 1-butyl-3-methylimidazolium acetate. The model integrates the dynamics of bubble oscillation, the thermodynamics applied to the interior of the bubble and at its interface, and the sonophysical and sonochemical events occurring in the presence of dissolved cellulose in the ionic liquid. The performed simulations shed light on the major physical effects of acoustic cavitation, namely the shockwave and microjet, as well as the sonochemical effects in terms of the degradation rate of the dissolved cellulose in the secondary reactional site, i.e., the interface. The predominance of the effects and its dependency of the acoustic frequency is tackled from an energetic point of view. It is demonstrated that 300 kHz offers the lowest heat flow across the bubble interface, lowering the chances for the sonochemical degradation of cellulose, while 200 kHz offers a significant degradation rate, attaining 71.4 mol·dm⁻³·s⁻¹, as well as harsher microjets and shockwaves with powers of 3300 and 900 mW at collapse, respectively. Full article

An investigation into the mechanisms of action on bacteria involving exposure to stress factors was conducted in this study. The effects of ultrasound on Escherichia coli K-12 MG1655 and its isogenic mutant, ∆gadW, under high power ultrasound treatments (26 kHz) were screened and identified by analysing their transcriptome differences between primary and secondary sequential treatments using RNA-Seq. This also helped to assess any developed protection for cells between different generations. According to our results, 1825 genes of all tested conditions were expressed, playing different roles in the cell. The expression of these genes is associated with DNA damage, cell membrane integrity, and also metabolic effects. The studied strains also showed different differential expressed genes (DEGs), with some genes being directly responsible for defence mechanisms, while others play an indirect effect due to cell damage. A gradual decrease in the expression of the genes, as we moved from just one cycle of ultrasound treatment to sequential treatment, was evident from a heat map analysis of the results. Overall, E. coli K-12 builds a self-protection mechanism by increasing the expression of genes involved in the respiration for increased growth, and production of flagellum and pili. It can be concluded that high power ultrasound is a technology that triggers several different defence mechanisms which directly link to E. coli. Full article

We investigate the possibility of modification of SnS₂ powder through sonochemical synthesis with the addition of an organic ligand. For that purpose, two organic dyes are used, Phenol Red and Anthraquinone Violet. All obtained powders are characterized using XRD, SEM, EDX, FT-IR, and UV-Vis investigations. Synthesized samples showed composition and structural properties typical for sonochemically synthesized SnS₂. However, investigation with the Tauc method revealed that SnS₂ powder modified with Phenol Red exhibits a significant shift in value of optical bandgap to 2.56 eV, while unmodified SnS₂ shows an optical bandgap value of 2.42 eV. The modification of SnS₂ powder with Anthraquinone Violet was unsuccessful. The obtained nanopowders were utilized as photocatalysts in the process of Metanil Yellow degradation, revealing that SnS₂ modified with Phenol Red shows about 23% better performance than the unmodified one. The mean sonochemical efficiency of the performed synthesis is also estimated as 9.35 µg/W. Full article