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Background: Diagnostic ultrasound or sonography is an image which can provide valuable information for diagnosing and treating a variety of diseases and conditions. This experiment was done to check the performance and evaluate the ultrasonic imaging system. There were three tests performed in this experiment: dead zone (transducer ring-down), vertical measurement calibration, and horizontal measurement calibration. Methods: The evaluation was made by performed all the tests with different depth on two different multipurpose phantom model #539. The tests were also performed by two different probes which were curved and flat (linear probe). The images were taken, and the measurements were made by electronic calipers on the ultrasound machine system. Observations and evaluations were done via all images and measurements taken. Results: The images formed by two various probes were different. The penetration settings were different since the depths were different. The depth influenced the penetrations to the formed image. From the comparison of all results and measurements recorded were all under the accepted value of the standard that was given by the manufacture of the phantom. Conclusion: Therefore, it can be concluded that the measurements were all not exceeding 2% of the standard value given based on the result that we get.

Platinum nanoparticles (Pt NPs) have attracted interest in catalysis and biomedical applications due to their unique structural, optical, and catalytic properties. However, the conventional synthesis of Pt NPs using the chemical and physical methods is constrained by the use of harmful and costly chemicals, intricate preparation requirement, and high energy utilization. Hence, this review emphasizes on the green synthesis of Pt NPs using plant extracts as an alternative approach due to its simplicity, convenience, inexpensiveness, easy scalability, low energy requirement, environmental friendliness, and minimum usage of hazardous materials and maximized efficiency of the synthesis process. The underlying complex processes that cover the green synthesis (biosynthesis) of Pt NPs were reviewed. This review affirms the effects of different critical parameters (pH, reaction temperature, reaction time, and biomass dosage) on the size and shape of the synthesized Pt NPs. For instance, the average particle size of Pt NPs was reported to decrease with increasing pH, reaction temperature, and concentration of plant extract.

This detailed review presents an overview of current research on the synthesis, surface modification, and applications of Iron oxide (Fe3O4) nanoparticles and iron oxide/gold (Fe3O4/Au) nanocomposites. The different synthesis techniques of Fe3O4 with various basic organic and inorganic modifications are presented. The applicability and role of inorganic and organic coating on iron oxide/gold core/shell schemes were explored. The trade-off between choices for surface functionalization related to specific applications such as imaging contrast agent, drug delivery carrier and therapeutic device using iron oxide/gold core/shell was also elaborated. The versatility of combining iron oxide/ and gold as nanocomposite as the choice for biomedical application is demonstrated in MRI, CT scan, drug delivery, biosensors, and hyperthermia application.

Gold nanoparticles (AuNPs) are becoming increasingly popular as drug carriers due to their unique properties such as size tenability, multivalency, low toxicity and biocompatibility. AuNPs have physical features that distinguish them from bulk materials, small molecules and other nanoscale particles. Their unique combination of characteristics is just now being fully realized in various biomedical applications. In this review, we focus on the research accomplishments and new opportunities in this field, and we describe the rising developments in the use of monodisperse AuNPs for diagnostic and therapeutic applications. This study addresses the key principles and the most recent published data, focusing on monodisperse AuNP synthesis, surface modifications, and future theranostic applications. Moving forward, we also consider the possible development of functionalized monodisperse AuNPs for theranostic applications based on these efforts. We anticipate that as research advances, flexible AuNPs will become a crucial platform for medical applications.

Current environmental concerns fostered a strong interest in extracting polymers from renewable feedstocks. Chitosan, a second most abundant polysaccharide after cellulose, may prove to be a promising green material owing to its renewability, inherent biodegradablity, natural availability, non-toxicity, and ease of modification. This review is intended to comprehensively overview the recent developments on the isolation of chitosan from chitin, its modification and applications as a reinforcing candidate for food packaging materials, emphasizing the scientific underpinnings arising from its physicochemical properties, antimicrobial, antioxidant, and antifungal activities. We review various chitosan-reinforced composites reported in the literature and comprehensively present intriguing mechanical and other functional properties. We highlight the contribution of these mechanically robust and responsive materials to extend the shelf-life and maintain the qualities of a wide range of food commodities. Finally, we assess critical challenges and highlight future opportunities towards understanding the versatile applications of chitosan nanocomposites.

COVID-19 is a major health threat across the globe, which causes severe acute respiratory syndrome (SARS), and it is highly contagious with significant mortality. In this study, we conduct a scenario analysis for COVID-19 in Malaysia using a simple universality class of the SIR system and extensions thereof (i.e., the inclusion of temporary immunity through the reinfection problems and limited medical resources scenarios leads to the SIRS-type model). This system has been employed in order to provide further insights on the long-term outcomes of COVID-19 pandemic. As a case study, the COVID-19 transmission dynamics are investigated using daily confirmed cases in Malaysia, where some of the epidemiological parameters of this system are estimated based on the fitting of the model to real COVID-19 data released by the Ministry of Health Malaysia (MOH). We observe that this model is able to mimic the trend of infection trajectories of COVID-19 pandemic in Malaysia and it is possible for transmission dynamics to be influenced by the reinfection force and limited medical resources problems. A rebound effect in transmission could occur after several years and this situation depends on the intensity of reinfection force. Our analysis also depicts the existence of a critical value in reinfection threshold beyond which the infection dynamics persist and the COVID-19 outbreaks are rather hard to eradicate. Therefore, understanding the interplay between distinct epidemiological factors using mathematical modelling approaches could help to support authorities in making informed decisions so as to control the spread of this pandemic effectively.

Graphical abstract, The 2019 novel coronavirus (2019-nCoV; severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) has witnessed a rapid and global proliferation since its early identification in patients with severe pneumonia in Wuhan, China. As of 27th May 2020, 2019-nCoV cases have risen to >5 million, with confirmed deaths of 350,000. However, Coronavirus disease (COVID-19) diagnostic and treatment measures are yet to be fully unraveled, given the novelty of this particular coronavirus. Hence, no drug or vaccine has been adapted for treatment, and the accuracy of the current diagnostic tests is debatable. Therefore, existing antiviral agents used for severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) were repurposed for COVID-19, taking their biological features into consideration. This study provides a concise review of the current and emerging detection and supervision technologies for SARS-CoV-2, which is the viral etiology of COVID19, and their performance characteristics, with emphasis on the novel Nano-based diagnostic tests (protein corona sensor array and magnetic levitation) and treatment measures (treatment protocols based on nano-silver colloids) for COVID-19.

The production of nanomaterials integrating diagnostic and therapeutic roles within one nanoplatform is important for medical applications. Such theranostics nanoplatforms could provide information on imaging, accurate diagnosis and, at the same time, could eradicate cancer cells. Fe3O4@Au core@shell nanoparticles (Fe3O4@AuNPs) have gained broad attention due to their unique innovations in magnetic resonance imaging (MRI) and photothermal therapy (PTT). Seed-mediated growth procedures were used to produce the Fe3O4@AuNPs. In these processes, complicated surface modifications, resulted in unsatisfactory properties. This work used the ability of the sonochemical approach to synthesize highly efficient theranostics agent Fe3O4@AuNPs with a size of approximately 22 nm in 5 min. The inner core of Fe3O4 acts as an MRI agent, whereas the photothermal effect stands accomplished by near-infrared absorption of the gold shell (Au shell), which results in the eradication of cancer cells. We have shown that Fe3O4@AuNPs have great biocompatibility and no major cytotoxicity has been identified. Relaxivity value (r2) of synthesized Fe3O4@Au NPs, measured at 233 mM−1s−1, is significantly higher than those reported previously. The as-synthesized NPs have shown substantial photothermal ablation ability on MCF-7 in vitro under near-infrared laser irradiation. Consequently, Fe3O4@AuNPs synthesized in this study have great potential as an ideal candidate for MR imaging and PTT.

One of the most widely used modalities of clinical imaging is computed tomography (CT). Recent reports of new contrast agents toward CT imaging have been numerous. The production of gold nanoparticles (AuNPs) as contrast agents for CT is primarily a topic of intense interest. AuNPs have beneficial features for this application, including excellent X-ray attenuation, flexible sizes and shapes, tailorable surface chemistry, excellent biocompatibility and high levels of contrast generating matter. AuNPs with a size of about 18.5 nm and semi-spherical shape were synthesized using a sonochemical method. The attenuation rate of X-rays as measured in Hounsfield units per unit concentration (HU/mg) was measured. Ultrasound treatment for a duration of five min has been shown to produce highly stable AuNPs in different media (AuNPs in water and phosphate-buffered saline (PBS) was &minus, 42.1 mV and &minus, 39.5 mV, respectively). The CT value (HU = 395) of the AuNPs increased linearly with an increase in the AuNP dosage. The results confirm the use of ultrasonic treatment for the production of metal nanostructures, particularly highly stable non-toxic AuNPs, with good morphology and high-quality crystal structure using an easy and fast method. Synthesized AuNPs have the potential to be used as a CT contrast agent in medical imaging applications.

A highly stable and magnetized citric acid (CA)-functionalized iron oxide aqueous colloidal solution (Fe3O4@CA) was synthesized by using a simple and rapid method of one-step co-participation via a chemical reaction between Fe3+ and Fe2+ in a NaOH solution at 65 °C, followed by CA addition to functionalize the Fe3O4 surface in 25 min. The NPs were synthesized at lower temperatures and shortened time compared with conventional methods. Surface functionalization is highly suggested because bare Fe3O4 nanoparticles (Fe3O4 NPs) are frequently deficient due to their low stability and hydrophilicity. Hence, 19 nm-sized Fe3O4 NPs coated with CA (Fe3O4@CA) were synthesized, and their microstructure, morphology, and magnetic properties were characterized using X-ray diffraction, transmission electron microscopy, Zeta potential, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. CA successfully modified the Fe3O4 surface to obtain a stabilized (homogeneous and well dispersed) aqueous colloidal solution. The Zeta potential value of the as-prepared Fe3O4@CA increases from − 31 to − 45 mV. These CA-functionalized NPs with high magnetic saturation (54.8 emu/g) show promising biomedical applications.

Upconversion (UC) of lanthanide-doped nanostructure has the unique ability to convert low energy infrared (IR) light to high energy photons, which has significant potential for energy conversion applications. This review concisely discusses the basic concepts and fundamental theories of lanthanide nanostructures, synthesis techniques, and enhancement methods of upconversion for photovoltaic and for near-infrared (NIR) photodetector (PD) application. In addition, a few examples of lanthanide-doped nanostructures with improved performance were discussed, with particular emphasis on upconversion emission enhancement using coupling plasmon. The use of UC materials has been shown to significantly improve the NIR light-harvesting properties of photovoltaic devices and photocatalytic materials. However, the inefficiency of UC emission also prompted the need for additional modification of the optical properties of UC material. This improvement entailed the proper selection of the host matrix and optimization of the sensitizer and activator concentrations, followed by subjecting the UC material to surface-passivation, plasmonic enhancement, or doping. As expected, improving the optical properties of UC materials can lead to enhanced efficiency of PDs and photovoltaic devices.

This study is a new attempt to synthesize gold nanoparticles (AuNPs) using the extract of fresh mature fruits of the Iraqi Prosopis farcta plant (Fabaceae). The synthesis has been performed under infrared (IR) irradiation treatment and compared with the heating procedure at 90 °C. P. farcta-AuNPs has been investigated as a nanocatalyst to remove Methylene blue (MB) dye from aqueous solutions. TEM, FE-SEM, EDX, XRD, size Distribution Report by Intensity, Zeta Potential, UV–Vis, GC-Mass and FTIR have been used to characterize the synthesized AuNPs. The color transformation of colloidal AuNPs under both IR radiation and heat confirmed the efficient reduction of Au+ to Au0 and its stabilization using P. farcta extract. AuNPs synthesized using IR were mainly spherical with an average diameter hydrodynamic size of 25.43 nm, and Zeta Potential of −26.5 mV. While AuNPs prepared using the heating treatment showed a quasi-spherical shape with an average size of 53.12 nm and Zeta Potential of −24.4 mV. FTIR analysis indicates that phenolic compounds of P. farcta extract are protected in the AuNPs synthesized by IR irradiation, but they are lost in another sample. Thus, the AuNPs bio-synthesized using IR radiation have higher colloidal stability, smaller size, more spherical and more preserved core–shell structure than Au NPs prepared using the heat treatment. Bionano-reduction of MB using synthesized AuNPs using IR irradiation best than synthesized using the heating procedure. This work encourages using IR irradiation as a new method to produce and improve AuNPs for catalytic handling.

Sonochemical synthesis (sonochemistry) is one of the most effective techniques of breaking down large clusters of nanoparticles (NPs) into smaller clusters or even individual NPs, which ensures their dispersibility (stability) in a solution over a long duration. This paper demonstrates the potential of sonochemistry becoming a valuable tool for the deposition of gold (Au) shell on iron oxide nanoparticles (Fe

Vertically aligned Al-doped ZnO nanorods (AZO-NRs) were grown on glass substrate using a chemical bath deposition (CBD) method at various temperatures between 80°C and 130°C. The results showed the Al content in the AZO-NRs strongly depends on the growth temperature. The optimum doping level was attained at 110°C. The morphology was maintained in each sample, and the lasing properties were investigated against the Al-doped variation. The sample with a high doping level exhibited superior random lasing, with high intensity and spectral width of less than 0.08 nm. The same sample also had the lowest pumping threshold of 0.192 mW. More importantly, this study showed the possibility of utilizing doping as a tuning parameter for random lasing, whereby a 7.3 nm redshift in the lasing peak was observed with increasing doping concentration. This study also placed an emphasis on AZO-NRs as potential candidates for tunable random laser devices.

Computed tomography (CT) imaging can be enhanced with the use of contrast agents. However, the conventionally used clinical small-molecule agents (Omnipaque) are encumbered by an array of constraints that include potentially toxic and unwanted side effects. Therefore, this study presents a facile plant-assisted synthesis of platinum nanoparticles (Pt NPs) that employs ultrasonic irradiation to improve the Hounsfield (HU) values for CT imaging. This “one-step one-pot”, eco-friendly and simple approach produced highly stable, biocompatible and ultrasmall Pt NPs colloidal with a mean diameter of 3.8 nm. The extract from Prosopis farcta (P. farcta) fruits served as both a reducing agent and stabilizer. The cell viability test demonstrated that HEK-293 cells remained viable after being subjected to high concentrations of Pt NPs. The X-ray attenuation of the as-synthesized Pt NPs (HU = 355) exceeds those of commercial NPs and conventionally prepared NPs. Thus, this research gives new insights into the use of plants to prepare novel contrast agents for molecular imaging.

Platinum nanoparticles (Pt NPs) with excellent physicochemical properties have been produced using various techniques, including sonochemistry method. However, the effect of solvent type on the irradiation power and structure, morphology and colloidal stability of Pt NPs synthesized via sonication has received less attention. In this work, Pt NPs were sonochemically-assisted green synthesized in various solvents (water, ethanol and methanol) using the Prosopis farcta fruits extract (PFFs) as a reducing agent. The structure, morphology and colloidal stability (surface charge) of the synthesized Pt NPs were characterized by X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Zeta potential, respectively, for exploring the physicochemical properties of Pt NPs. The Pt NPs produced were a face-centred cubic structure of crystalline Pt and mainly semi-spherically shaped with sizes range from1.6 nm to 5 nm. It was found that the interaction of the solvent with Pt NPs in the presence of ultrasound plays an important role in modulating particle size and surface charge. TEM results demonstrated the smallest NPs size of Pt NPs was acquired in methanol. The stability of Pt NPs in water, ethanol and methanol was −31 mV, +2.14 mV and −6.76 mV, respectively. This shows that the size and surface charge (zeta potential) of Pt NPs depends on the solvent's physical properties (viscosity, boiling point, and polarity).

This paper reports the effects of low energy X-ray irradiation doses on the structures, morphologies and absorbance of some colloidal gold nanoparticles (AuNPs) produced in distilled water via the one-step pulse laser ablation in liquid (PLAL) method. An Nd:YAG pulse laser (wavelength of 1064 nm and fluence ranges of 0.076–7.692 J/cm2) was used to ablate the gold plate surface (acted as a target) immersed in distilled water (10 mL). The laser pulse duration was adjusted to 2.5 min (1000 pulses), 5 min (2000 pulses). Simultaneously, the colloidal suspension was irradiated with low energy X-ray. The obtained samples were characterized thoroughly using different analytical instruments. High quality, pure, surfactant-free AuNPs with well-defined morphology and broad size distribution were achieved. The recorded values of the Zeta potential of the as-synthesized AuNPs were increased from -33.1 to -41.2 mV which was mainly due to the low energy X-ray dose-mediated photo- and Auger-electrons generation plus the fragmentation of the bigger NPs into highly stable tinier species inside the colloidal suspension. The observed blue-shift in the absorbance peaks of the NPs centered at 523, 529, and 526 nm irradiated with the corresponding fluences of 0.076, 3.846, and 7.692 J/cm2 was ascribed to the quantum size effects. It is established that the synergy between laser ablation and low energy X-ray does may be effective to prepare the contaminants-free AuNPs in the liquid suspension in a simple rapid and cost-effective way.

Gold nanoparticles (AuNPs) can be easily synthesised using several methods for various applications in the industrial and medical sectors. However, their performance as a catalyst has not yet to be appropriately studied and optimised due to large size distribution and high agglomeration property. In this work, AuNP were synthesized by a sonochemical method using sodium citrate as a reducing agent and capping material. A Vibra-Cell ultrasonic solid horn with a half-inch tip size, frequency of 20 kHz and different ultrasound output powers (12, 20 and 36 W) was used in the synthesis. The as-synthesized AuNPs exhibited a spherical morphology with smooth geometry, excellent stability and high monodispersity after 10 min of sonication. AuNPs sizes decreased with increased sonication output power, which implies that the particle size, surface plasmon resonance, stability and monodispersity of the AuNPs depended on ultrasound output power and reaction time. Overall, this study showed that the sonochemical synthesis of AuNPs was an easy and controllable approach and can be potentially applied to fabricate other nanosized particles. AuNP's catalytic efficiency for the degradation of methylene blue has a fast decoloration rate of about 10 min.

Core@shell nanoparticles (Fe3O4@Au CSNPs) have multiple functions obtained in one stable entity and thus have been extensively investigated. Fe3O4 NPs have unique superparamagnetic properties which allow for their application in different fields, and Au NPs stand out in biomedical applications because of their chemical stability, oxidation resistance and high-quality intrinsic optical properties. Combining Fe3O4 and Au NPs in one core@shell nanostructure is a promising strategy for diagnostic biomedical applications. However, the conventional direct methods for Fe3O4@Au CSNP synthesis are laborious and time consuming. Therefore, this study presents a facile and rapid sonochemical technique of synthesising Fe3O4@Au CNPs with excellent physicochemical properties for magnetic resonance imaging (MRI) and computed tomography (CT) scan. A Vibra Cell ultrasonic solid horn with a tip size of ½ inch, 20 kHz frequency and power output of 750 W were used, and the synthesis is achieved in just 10 min. Several techniques were used to characterise the Fe3O4@Au CSNPs and confirmed their average size of 21 nm and the formation of spherical Au shell on the Fe3O4 core. The Fe3O4@Au CNPs showed good biocompatibility and great potential as a dual-mode contrast agent for MRI/CT imaging. The transverse relaxivity values and X-ray attenuation of the as-synthesised NPs (222.28 mM−1s−1 and HU = 418) are greater than those of NPs prepared using conventional methods and commercial NPs. This work reveals considerable progress on Fe3O4@Au CSNPs by providing a facile and rapid method to synthesise high-quality Au-coated Fe3O4 NPs.

This study reports the synthesis and optimization of the sonochemical method for the functionalization of iron oxide nanoparticles (Fe3O4NPs) with gold nanoparticles (AuNPs) shells using the surface response methodology (RSM). The Au shell is coated on Fe3O4 NPs using a Vibra-Cell ultrasonic solid horn with tip size, frequency and power output of ½ inch, 20 kHz and 750 w, respectively within 8 min. Using RSM, experimental runs of 14 different combinations of HAuCl4 concentration, sodium citrate (SC) concentration, and sonication amplitude (independent variables) were performed with two centered points to optimize the experimental conditions. Variance analysis (ANOVA) was applied to achieve the best optimum conditions for the experimental data. The targeted zeta potential of –46.125 mV was achieved under the optimum conditions of 10 ml of HAuCl4, 30 ml of SC and sonication amplitude of 40%, which is consistent (about 99.2%) with the actual average zeta potential (–45.8 mV). The stability and monodispersion of Fe3O4NPs improved following modification to Fe3O4@Au, as indicated by the increase in zeta potential from –24.2 mV to –45.8 mV. The saturation magnetization (Ms) value of Fe3O4 was 54 emu/g, while that of Fe3O4@Au NP is 38 emu/g. In general, the sonochemical method effectively synthesizes highly stable and monodisperse Fe3O4@Au NPs with an average size of about 20 nm within 8 min.

This research is the first attempt on using fruitbodies of Portabello mushroom (Agaricus bisporus) as a newly mycoreducer agent used in the myco-synthesis of gold nanoparticles (AuNPs). The biosynthesized AuNPs were described for their chemical and physical characteristics by UV–vis spectra, the change in color, AFM, FESEM, XRD, Zeta Potential, DLS, and FT-IR analyses. The AuNP was investigated for its activity to decolorize MB (Methylene Blue) dye. However, the magenta color of gold nanoparticles indicated that the colloidal AuNPs contained a mixture of oval, spherical, drum-like, hexagonal, and triangular shapes reaches 53 nm in the diameter. Clearly, XRD exhibited that the formed Au nanoparticles in this study were crystalline. In contrast, data of Zeta Potential and DLS exhibited that myco-synthesized gold NPs showed remarkable aggregation and stability characteristics in the colloidal AuNPs solution. FTIR revealed the attachment of the amino acid, polysaccharide, and phenol as a mycoreducer agent capped gold NPs. The degradation activity showed that decolorizing Methylene Blue increased with the increasing the time of incubation in the finding of gold NPs. The mycosynthesized AuNPs using extracts of Agaricus bisporus can act as nanocatalysts in the reduction of Methylene Blue which showed the best decolorization at 97.98%.

This study presents a new, facile and fast strategy to synthesize platinum nanoparticles (Pt NPs) in methanol under ultrasonic irradiation. Here, for the first time, methanol was used to reduce Pt2+ to Pt0 in the absence of a reductive and surfactant. The hydroxyl free radical (OH•) liberated from methanol under the sonication effect facilitates the formation of PtNPs by aiding the production of nucleation sites and donating electrons to Pt2+. The results show that the PtNPs with an average diameter of 3.9 nm, high percentage PtNPs yield and pure Pt with face-centered cubic (fcc) structure can be synthesized sonochemically in one minute in the presence of methanol. The catalytic efficiency of the obtained PtNPs for degradation of methyl blue (MB) in an aqueous solution showed a rapid rate of decolorization of MB dye.

Pt nanoparticles (NPs) are successfully synthesized via sonochemically assisted green synthesis by using Prosopis farcta fruit extract (P. farcta) as a reducing agent and stabilizer. The synthesized Pt NPs are fully characterized to confirm the morphology, structure, colloidal stability, and biocompatibility. These Pt NPs exhibit excellent physicochemical properties and colloidal stability in aqueous solution with a zeta potential value of −38.9 mV. The high stability and biocompatibility of the Pt NPs can be attributed to the organic compounds contained in the P. farcta extract. The organic compound-coated Pt NPs are identified. The high energy produced by ultrasound irradiation facilitates a covalent interaction between the P. farcta extract and the Pt NPs despite the short duration of synthesis. Special attention has been given to explain the underlying complex processes that describe the reaction mechanism of Pt NPs synthesized by P. farcta under sonication. Results showed that the cell viability of the synthesized Pt NPs is unaffected (nontoxic) at relatively high concentrations (100 μg/ml), thereby making it a promising method for synthesizing Pt NPs that are relevant for medical applications.

Platinum nanoparticles (Pt NPs) were synthesized, through sonochemical and conventional methods, using the extract from Prosopis farcta fruits (PFFs) as a reducing agent and stabilizer. The structure, morphology and colloidal stability of Pt NPs synthesized by both methods were characterized and compared. A Vibra-Cell ultrasonic solid horn with tip size, frequency, a power output of 1 2 inch, 20 kHz and 750 watts, respectively, were used in the sonochemical synthesis of Pt NPs for 30 min. The formation of amorphous or crystalline Pt NPs is attributed to rapid heating/cooling cycles of the cavitation microbubbles generated by the sonication. The purity, uniformity and crystallinity of Pt NPs synthesized by the sonochemical method were shown to be better than those obtained from the conventional method. The Pt NPs also exhibited smaller particle size with higher colloidal stability and hydrodynamic size. The results confirm that the irradiation power of the sonochemical method enhances the crystalline properties of nanoparticles and hinders their agglomeration. Therefore, the sonochemical method can synthesize Pt NPs with better physicochemical properties compared to conventional methods.

This study is the first report on the usage of fresh fruiting bodies of Enoki mushroom (Flammulina velutipes) as a new green reducer agent incorporated in the mycosynthesis of gold nanoparticles. The mycosynthesized AuNP was characterized for its physical and chemical properties using optical observation, UV–vis spectrometer, FESEM, AFM, DLS, XRD, Zeta Potential, and FTIR analyses. The optimized AuNPs were then tested for its efficacy in the decolorization of Methylene Blue (MB). The purple color of AuNPs indicates that the solution contains a mixture of triangular, spherical, and irregular shapes with an average of size 74.32 nm. The pattern of XRD clearly showed that the formed AuNPs were crystalline while DLS and Zeta Potential data showed that mycosynthesized AuNPs exhibited good stability and aggregation properties in colloidal form. FTIR showed the attachments of polysaccharides, amino acids and phenol as reducer agents on AuNPs. The efficacy test exhibited that the degradation of MB increased with the increase of the incubation time in presence of AuNPs. The proof-of-concept that mycosynthesized AuNPs by fungal natural organic materials of Flammulina velutipes can act as catalysts in reducing the MB dye is proven by the best decolorization of MB at 75.35 % after 4 h soak.

Sonochemical synthesis (sonochemistry) is one of the most effective techniques of breaking down large clusters of nanoparticles (NPs) into smaller clusters or even individual NPs, which ensures their dispersibility (stability) in a solution over a long duration. This paper demonstrates the potential of sonochemistry becoming a valuable tool for the deposition of gold (Au) shell on iron oxide nanoparticles (Fe3O4 NPs) by explaining the underlying complex processes that control the deposition mechanism. This review summarizes the principles of the sonochemistry method and highlights the resulting phenomenon of acoustic cavitation and its associated physical, chemical and thermal effects. The effect of sonochemistry on the deposition of Au NPs on the Fe3O4 surface of various sizes is presented and discussed. A Vibra-Cell ultrasonic solid horn with tip size, frequency, power output of ½ inch, 20 kHz and 750 W respectively was used in core@shell synthesis. The sonochemical process was shown to affect the surface and structure of Fe3O4 NPs via acoustic cavitation, which prevents the agglomeration of clusters in a solution, resulting in a more stable dispersion. Deciphering the mechanism that governs the formation of Au shell on Fe3O4 core NPs has emphasized the potential of sonication in enhancing the chemical activity in solutions.

This work aims to find a new green reducer agent for synthesis gold nanoparticles (AuNPs). Fresh fruiting bodies of shiitake mushroom (Lentinula edodes) were used to mycosynthesize AuNPs, which were characterized using change in color, UV–vis, FE-SEM, AFM, Zetasizer, Zeta Potential, XRD, EDX, and FTIR analyses. The purple color is a sign of biosynthesizing AuNPs. The UV–vis spectrum showed an absorption peak at 568 nm due to incitation of Surface Plasmon Resonance in AuNPs colloidal solution. FE-SEM images exhibited that most of the AuNPs have triangular, hexagonal, spherical and irregular shapes with an average of sizes reached 72 nm. The XRD pattern clearly explained that AuNPs formed in this work were crystalline. The EDX proved that the nanoparticles are AuNPs. FTIR exhibited the role of amino acids, polysaccharides and phenols as reducer agents. The value of zeta potential indicates good quality with the aggregation of particles.