One-step Ultrasonication Research Articles

Neem biomass derived carbon quantum dots synthesized via one step ultrasonification method for ecofriendly methylene blue dye removal

This article presents a one-step ultrasonication technique for generating biomass carbon dots (BCDs) from neem bark (Azadirachta indica) powder. The BCDs were characterized using modern techniques such as UV–Vis, FTIR, Raman, XRD, HRTEM, FESEM, EDAX, and Zeta potential analyses. Unlike traditional nanocomposite bed systems, this study utilized BCDs as a liquid-phase adsorbent for the regenerative adsorption of the environmentally harmful dye, methylene blue (MB), through an in-situ precipitation reaction. This involved the formation of BCDs-MB adduct via an electrostatic mechanism. The adsorption capacity and percentage of removal were remarkable at 605 mg g–1 and 64.7% respectively, exceeding various solid-based adsorption methods in the literature. The Langmuir isotherm and pseudo-second-order kinetics model provided an excellent fit for this system. The calculated thermodynamic parameter, Gibbs free energy change (ΔG) was negative, indicating a spontaneous, exothermic, and physisorption-based mechanism. The regenerative capacity of our system was further demonstrated by successfully extracting and recovering the MB dye (64%) using ethyl alcohol as the solvent. This method provides an efficient means of recovering valuable cationic organic dye compounds from contaminated environments.

Green synthesis of carbon quantum dots from teak leaves biomass for in situ precipitation and regenerative-removal of methylene blue-dye.

The objective of this study was to completely eliminate environmentally harmful cationic organic dye from aqueous solutions using the one-step ultrasonication method, renowned for its energy efficiency, user-friendliness, and minimal requirement for chemical resources, making it particularly suitable for large-scale applications. To achieve effective environmental remediation, we employed carbon dots derived from teak leaf biomass (TBCDs) layered with graphene oxide. We conducted a thorough characterization of the TBCDs using UV-vis spectroscopy (with absorption peaks at λmax = 208 and 276nm), FTIR spectroscopy (confirming the presence of various functional groups including -OH, -CH, C = O, COO-, C-O-C, and = C-H), Raman spectroscopy (with bands at 1369cm-1 (D-Band) and 1550cm-1 (G-Band), and an intensity ratio (ID/IG) = 0.88, indicating structural defects correlated with the sp3 hybridization sites on the TBCDs), XRD analysis (indicating an amorphous nature of particles), HRTEM imaging (showing homogeneous dispersal of TBCDs with typical sizes ranging from 2 to 10nm), FESEM analysis (showing a flat surface and minuscule particles), and Zeta potential analysis (revealing a surface charge peak at -51.0mV). Our adsorption experiments yielded significant results, with a substantial 50.1 % removal rate and an impressive adsorption capacity of 735.2mg g-1. Theoretical adsorption parameters were rigorously analyzed to understand the adsorption behavior, surface interactions, and mechanisms. Among these models, the Langmuir isotherm in conjunction with pseudo-second-order kinetics provided an exceptional fit (with R2 values closer to 1) for our system. The Gibbs free energy (ΔG) was found to be negative at all temperatures, indicating the spontaneity of the reaction. Regarding mechanism, electrostatic attraction ((+ve) MB dye + (- ve) TBCDs), π-π stacking adsorption facilitated by the graphitic structure, formation of multiple hydrogen bonds due to polar functional groups, and a pore-filling mechanism wherein the cationic MB dye fills the pores of TBCDs with graphene oxide layers, forming an adduct were identified. Furthermore, we demonstrated the regenerative capacity of our system by effectively extracting and recovering the MB dye (with a regeneration rate of 77.1%), utilizing ethyl alcohol as the solvent. These findings not only provide valuable insights into the adsorption capabilities of TBCDs but also highlight the potential of our approach in the recovery of expensive cationic organic dye compounds from polluted environments.

Transformation of bulk MnO2 to fluorescent quantum dots for selective and sensitive detection of ferric ions and ascorbic acid by turn-off-on strategy

MnO2 nanostructure has a unique light absorption ability and redox feature, due to which it is mainly used as a fluorescence quencher. However, its quantum dots can also act as a self-fluorescent nanomaterial with exclusive properties for sensing applications. Therefore, a cheap and straightforward route for fabricating citric acid-functionalized MnO2 quantum dots (CA-MnO2 QDs) was proposed through one-step ultrasonication of bulk MnO2 in the presence of citric acid as acidifying and stabilizing agent. The prepared CA-MnO2 QDs exhibited high photostability, good water solubility, high photoluminescence (PL) stability from pH range 5 to 9, and significant fluorescence quantum yield value, i.e., 13.3 %. Further, CA-MnO2 QDs was used for the detection of Fe3+ ions with a detection limit of 43 nM, based on dynamic quenching. The fluorescence quenching mechanism was confirmed by determining different photophysical parameters such as fluorescence quantum yield, average lifetime values, radiative constants (kr), non-radiative rate constants (knr), rate of electron transfer (kET), and electron transfer efficiency (ΦEET). The CA-MnO2 QDs in the presence of Fe3+ was used for the detection of ascorbic acid with a detection limit of 90 nM based on the redox reaction between Fe3+ ions and AA. Furthermore, the developed sensing probe was also used to detect Fe3+ ions and AA in real samples, i.e., iron and AA supplements, respectively.

A facile approach to prepare water-soluble magnetic metal (oxide) frameworks based on Na,Ca alginate and maghemite

A one-step ultrasonication technique for the preparation of magnetic metal (oxide) organic frameworks (MOFs) with a size of >135 nm based on sodium alginate crosslinked with Ca 2+ ions and maghemite (γ-Fe 2 O 3 ) nanoparticles with sizes from 7 to 20 nm was proposed. The MOFs were characterized by Mössbauer spectroscopy, TEM, magnetometry, and UV-VIS and IR spectroscopy. The grid (crosslinks) preliminarily formed by Ca 2+ ions plays an important role in the stabilization of maghemite nanoparticles, and the resulting MOFs can be used as magnetic carriers in systems for hyperthermia and drug delivery.

A facile approach to prepare water-soluble magnetic metal (oxide) frameworks based on Na,Ca alginate and maghemite

A one-step ultrasonication technique for the preparation of magnetic metal (oxide) organic frameworks (MOFs) with a size of >135 nm based on sodium alginate crosslinked with Ca2+ ions and maghemite (γ-Fe2O3) nanoparticles with sizes from 7 to 20 nm was proposed. The MOFs were characterized by Mossbauer spectroscopy, TEM, magnetometry, and UV-VIS and IR spectroscopy. The grid (crosslinks) preliminarily formed by Ca2+ ions plays an important role in the stabilization of maghemite nanoparticles, and the resulting MOFs can be used as magnetic carriers in systems for hyperthermia and drug delivery.

Injectable Ultrasonication-Induced Silk Fibroin Hydrogel for Cartilage Repair and Regeneration.

Articular cartilage lacks both a nutrient supply and progenitor cells. Once damaged, it has limited self-repair capability. Cartilage tissue engineering provides a promising strategy for regeneration, and the use of injectable hydrogels as scaffolds has recently attracted much attention. Silk fibroin (SF) is an advanced natural material used to construct injectable hydrogels that are nontoxic and can be used efficiently in crosslinking applications. The objective of the present work was to develop an injectable hydrogel using SF in a novel one-step ultrasonication crosslinking method. Gelation kinetics and the characteristics of ultrasonication-induced SF (US-SF) hydrogels were systematically evaluated. The cytocompatibility of US-SF hydrogels was evaluated using rabbit chondrocytes, the Cell Counting Kit-8 testing, and immunofluorescence staining. Furthermore, the in vivo cartilage regenerative ability of US-SF hydrogels was confirmed following subcutaneous administration in nude mice and in situ injections in rabbit osteochondral defect models. These results suggest that US-SF hydrogels could be potential candidates for cartilage repair and regeneration. Impact statement Injectable silk fibroin hydrogel is a promising strategy for cartilage tissue engineering. The transition from solution state to gel state can be fabricated by both physical and chemical methods. However, the complexing protocol and toxicity of these methods remain hindrances to further application. In this study, a one-step ultrasonication method was developed. The novel ultrasonication-induced silk fibroin hydrogel showed satisfactory physicochemical and biomechanical properties. In vitro and in vivo experiments proved that it could promote cartilage regeneration, indicating that it may be a potential solution for cartilage repair and regeneration.

Antimicrobial Activities of Zn-Doped CuO Microparticles Decorated on Polydopamine against Sensitive and Antibiotic-Resistant Bacteria

A polydopamine (PDA) composite was synthesized by depositing Zn-doped CuO (Zn@CuO) particles on polydopamine by one-step ultrasonication. XPS, XRD, and FTIR confirmed the formation of spherical Zn@...

Fabrication and evaluation of nanocontainers for lipophilic anticancer drug delivery in 3D in vitro model.

Presently, most of anticancer drugs are high toxic for normal cells and, and as a result, they have severe side effects. Moreover, most of the formulations are lipophilic and have poor selectivity. To overcome these limitations, various drug delivery systems could be proposed. The aim of the current study was to fabricate novel polysaccharide nanocontainers (NC) by one-step ultrasonication technique and to evaluate their accumulation efficacy and cytotoxicity in 2D (monolayer culture) and 3D (tumor spheroids) in vitro models. NC with mean sizes in a range of 340-420 nm with the core-shell structure are synthetized and characterized. The NC shell is composed from diethylaminoethyl dextran/xanthan gum polyelectrolyte complex, while the hydrophobic core was loaded with the lipophilic anticancer drug thymoquinone. To enhance NC accumulation in human breast adenocarcinoma MCF-7 cells, the NC surface was modified with poly-L-lysine (PLL) or polyethylene glycol. Cell uptake of the NC loaded with Nile Red into the tumor cells was investigated by laser scanning confocal microscopy, fluorescent flow cytometry and fluorimetry. Modification of the NC with PLL allowed to obtain the optimal drug delivery system with maximal cytotoxicity, which was tested by MTT-test. The developed NC are promising for lipophilic anticancer drug delivery.

Refolding with Simultaneous Purification of Recombinant Serratia marcescens Lipase by One-Step Ultrasonication Process.

A new lipase from Serratia marcescens SRICI-01 (Trx-SmL) was successfully overexpressed in Escherichia coli with thioredoxin (Trx) fusion tag. Intriguingly, the concentration of potassium phosphate buffer (KPB) showed significant impact on the aggregation state of Trx-SmL during ultrasonic disruption. The proportion of inclusion bodies increased dramatically with the increase of KPB concentration from almost completely soluble in 10mM KPB to insoluble in 200mM KPB. Based on this new finding, a novel method for refolding and purification of recombinant Trx-SmL was developed by one-step ultrasonication. The Trx-SmL was firstly precipitated in 200mM KPB, washed for three times, and subsequently subjected to ultrasonic process in 10mM KPB where refolding and purification occurred simultaneously. This established method was proved to be a straightforward, economical, and efficient purification approach to facilely obtain recombinant Trx-SmL protein with high purity (> 90%) and activity recovery yield (> 80%) from cell lysates. The application potential of the purified fusion Trx-SmL was further demonstrated by kinetic bioresolution of (±)-trans-3-(4-methoxyphenyl)glycidic acid methyl ester [(±)-MPGM] producing optically pure (-)-MPGM, a key intermediate for diltiazem, with an overall yield of 41.5% and ee of 99%.

3D assembly based on 2D structure of Cellulose Nanofibril/Graphene Oxide Hybrid Aerogel for Adsorptive Removal of Antibiotics in Water

Cellulose nanofibril/graphene oxide hybrid (CNF/GO) aerogel was fabricated via a one-step ultrasonication method for adsorptive removal of 21 kinds of antibiotics in water. The as-prepared CNF/GO aerogel possesses interconnected 3D network microstructure, in which GO nanosheets with 2D structure were intimately grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward the antibiotics. The removal percentages (R%) of the antibiotics were more than 69% and the sequence of six categories antibiotics according to the adsorption efficiency was as follows: Tetracyclines > Quinolones > Sulfonamides > Chloramphenicols > β-Lactams > Macrolides. The adsorption mechanism was proposed to be electrostatic attraction, p-π interaction, π-π interaction and hydrogen bonds. In detail, the adsorption capacities of CNF/GO aerogel were 418.7 mg·g−1 for chloramphenicol, 291.8 mg·g−1 for macrolides, 128.3 mg·g−1 for quinolones, 230.7 mg·g−1 for β-Lactams, 227.3 mg·g−1 for sulfonamides, and 454.6 mg·g−1 for tetracyclines calculated by the Langmuir isotherm models. Furthermore, the regenerated aerogels still could be repeatedly used after ten cycles without obvious degradation of adsorption performance.

One-Step Preparation of Graphene Oxide/Cellulose Nanofibril Hybrid Aerogel for Adsorptive Removal of Four Kinds of Antibiotics

Via a one-step ultrasonication method, cellulose nanofibril/graphene oxide hybrid (GO-CNF) aerogel was successfully prepared. The as-prepared GO-CNF possessed interconnected 3D network microstructure based on GO nanosheets grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward four kinds of antibiotics. The removal percentages (R%) of these antibiotics were 81.5%, 79.5%, 79.1%, and 73.9% for Doxycycline (DXC), Chlortetracycline (CTC), Oxytetracycline (OTC), and tetracycline (TC), respectively. Simultaneously, the adsorption isotherms were well fitted to Langmuir model and kinetics study implied that the adsorption process was attributed to pseudo-second-order model. The maximum theoretical adsorption capacities of GO-CNF were 469.7, 396.5, 386.5, and 343.8 mg·g−1 for DXC, CTC, OTC, and TC, respectively, calculated by the Langmuir isotherm models. After five cycles, importantly, the regenerated aerogels still could be used with little degradation of adsorption property. Consequently, the as-synthesized GO-CNF was a successful application of effective removal of antibiotics.

Ultrasonically Assisted Polysaccharide Microcontainers for Delivery of Lipophilic Antitumor Drugs: Preparation and in Vitro Evaluation.

High toxicity, poor selectivity, and severe side effects are major drawbacks of anticancer drugs. Various drug delivery systems could be proposed to overcome these limitations. The aim of this study was to fabricate polysaccharide microcontainers (MCs) loaded with thymoquinone (TQ) by a one-step ultrasonication technique and to study their cellular uptake and cytotoxicity in vitro. Two MC fractions with a mean size of 500 nm (MC-0.5) and 2 μM (MC-2) were prepared and characterized. Uptake of the MCs by mouse melanoma M-3 cells was evaluated in both 2D (monolayer culture) and 3D (multicellular tumor spheroids) models by confocal microscopy, flow cytometry, and fluorimetry. The higher cytotoxicity of the TQ-MC-0.5 sample than the TQ-MC-2 fraction was in good correlation with higher MC-0.5 accumulation in the cells. The MC-0.5 beads were more promising than the MC-2 particles because of a higher cellular uptake in both 2D and 3D models, an enhanced antitumor effect, and a lower nonspecific toxicity.

Ultrasonication-assisted one-step self-assembly preparation of biocompatible fluorescent-magnetic nanobeads for rare cancer cell detection

Multifunctional nanomaterials simultaneously possessing attractive properties, such as strong fluorescent intensity, excellent superparamagnetic behavior, easy modification and good biocompatibility, are always desired in a wide range of applications. In this work, we present a facile ultrasonication-assisted one-step self-assembly strategy for the fabrication of smart fluorescent-magnetic nanobeads (FMNBs) without using a matrix. Via one-step ultrasonication, organic-soluble superparamagnetic nanoparticles (MNPs) and quantum dots (QDs) were automatically encapsulated by amphiphilic (2-hydroxyl-3-dodecanoxyl) propylcarboxymethylchitosans (HDP-CMCHSs) through hydrophobic interaction to form hydrophilic FMNBs, presenting a good QD fluorescent property and a strong MNP magnetic response. The outer surface of the FMNBs was derived from natural biopolymer chitosans, enabling FMNBs with good biocompatibility and convenience for biological modification. As-prepared FMNBs can be easily modified with streptavidin, facilitating bioconjugation with biotin-labeled human epidermal growth factor (hEGF). hEGF-functionalized FMNBs are able to specifically recognize and capture rare target cells spiked in white blood cells, and the recovered cells can be further cultured for a long time. All of these excellent properties make nanobeads promising for circulating tumor cell (CTC) detection.

Adsorptive removal of methylene blue by rhamnolipid-functionalized graphene oxide from wastewater

In this article, a rhamnolipid-functionalized graphene oxide (RL-GO) hybrid was prepared by one-step ultrasonication and adsorptive removal of methylene blue (MB) from both artificial and real wastewater by the RL-GO was investigated. The Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) area and Zeta potential analysis were used to characterize the adsorbent. The results showed that RL-GO had abundant functional groups and a mesopores feature. MB adsorption by the RL-GO increased with increase in adsorbent dose, pH, temperature and initial MB concentration, while it was insensitive to ionic strength variation. The adsorption kinetics fitted well to the pseudo-second-order model with correlation coefficients greater than 0.999. The Intra-particle diffusion and Boyd's film-diffusion models showed that the rate-controlled step was dominated by film-diffusion in the beginning and then followed by intra-particle diffusion. The adsorption isotherm was fitted by adsorption models with the suitability in order of BET > Freundlich > Langmuir > Temkin, based on comparison between correlation coefficients. Thermodynamic analysis of equilibriums suggested that the adsorption MB on RL-GO was spontaneous and endothermic. The adsorption mechanism was also proposed to be electrostatic attraction, π–π interaction and hydrogen bond. In addition, the real wastewater experiment, the regeneration study and the comparative cost analysis showed that the RL-GO composites could be a cost-effective and promising sorbent for MB wastewater treatment owing to its high efficiency and excellent reusability.

A facile strategy to recycle template P123 from mesoporous aluminosilicates by ultrasonic extraction

High synthesis cost of mesoporous aluminosilicates (MA) limits their practical application. Recycling of copolymer template employed in preparation of MA is an effective way to reduce the synthesis cost. An ultrasonic extraction strategy for recycling of organic template P123 in MAs is reported. Effects of different extraction parameters on P123 recovery are investigated and the optimum conditions are obtained. 75.0% P123 is recovered from MAs within 10min by one-step ultrasonication. Characterizations indicated that the resulting P123-free MA (MA-U) exhibits excellent properties compared with that of calcined products. Moreover, recovered P123 can be employed to synthesize high hydrothermally stable MA. This investigation provides a facile strategy to recycle P123 from MA.

Graphene oxide microspheres prepared by a simple, one-step ultrasonication method

We demonstrate herein a simple, one-step method for preparing stabilized microspheres of graphene oxide (GO), by applying ultra-sonic power to a biphasic system. The microsphere's size was affected by the pH of the aqueous solution, ranging from a few mm to μm. Further characterization indicated that the microsphere's inner content is composed mainly of organic solvents, though water and GO molecules may be also present at the microsphere's core. The microspheres were stable for several months without a significant conformation change. We predict that the stability arises from hydrophobic and hydrophilic interactions between the GO sheets and the solvents. Changing the organic solvent resulted in changes in the microsphere's morphology.

Can Graphene be an Electrode Support for Pt in Formic Acid Electrooxidation?

Formic acid electrooxidation over Pt deposited on two types of graphene supports are examined. The first support was prepared by rigorous chemical reduction of graphite oxide (GO) to form pure graphene (GCH). The second support is prepared by simultaneous reduction and functionalization of GO with ethylenediamine (GUE) by a one-step ultrasonication method. GUE show a significant shift in the HCOOH oxidation onset potential compared to GCH as well as other forms of commercial carbon supports. A comparative analysis of Pt activity towards formic acid electrooxidation over glassy carbon (GC) shows the following trend: Pt-GC-GUE>Pt-GC-GCH> HiSpec 3000 > Pt-GC-Vulcan XC-72.