Composite Nanoparticles Research Articles

Mapping the Nanotechnology Patent Landscape in the Field of Cancer.

Currently, cancer is still a significant disease that seriously endangers human health. Therefore, advanced diagnostic technology and treatment protocols are urgently needed. The rapid development of nanotechnology is expected to provide new ideas for cancer diagnosis and treatment. The research aims to comprehensively demonstrate the hotspots of nanotechnology applications in cancer. In this study, an International Patent Classification codes co-occurrence network is constructed to visualize the technology landscape by simultaneously locating and ranking technologies that play an integral role in nanotechnology diffusion and bridging in the field of cancer. In addition, community identification and topic modeling highlight the latent topics in patent documents. The visualization results of the patent network yield five main clusters: Cluster 0 is a nanoparticle composition delivery system with liposomes as the primary carrier. Cluster 1 is mainly represented by nano-immunotherapy with immune checkpoint inhibitors. Cluster 2 is nano phototherapy based on photodynamic therapy and photothermal therapy. Cluster 3 is diagnostic imaging involving nanotechnology. Cluster 4 is a drug delivery system with nanovesicles and albumin nanoparticles as carriers. It was found that carriers represented by liposomes, vesicles, and albumin nanoparticles are essential nanomaterials in the current anticancer drug delivery systems. Integrating next-generation immunosuppressants and nanotechnology will become an important development direction for future immunotherapy. Organic/inorganic nanomaterials are pivotal in cancer imaging diagnosis and phototherapy.

Rapidly synthesizing magneto-thermal adjustable high entropy alloy nanoparticles on carbon fiber surface for enhancing electromagnetic wave absorption, thermal conductivity and interface compatibility of composites

It is a significant challenge to develop a fast carbon fiber (CF) surface modification method that could generate a simple multifunctional CF surface, especially in the field of electromagnetic wave (EMW) and thermal regulation. Herein, the FeCoNiAlMn high-entropy alloy (HEA) nanoparticles modified CF (HEA-CF) was successfully prepared by microwave induced carbon thermal shock (MCTS) in a few seconds. The HEA-CF possessed magneto-thermal adjustability by controlling the elemental composition and crystal structures of HEA nanoparticles. It exhibited outstanding dielectric-magnetic loss and phonon heat transfer capability. Moreover, HEA nanoparticles and cellulose nanofibers on CF surface also formed multiscale interfacial reinforced structure. Consequently, HEA-CF/Polyamide 6 (PA6) composites demonstrated extraordinary versatility. MCTS5s-CF/PA6 exhibited the strongest absorption with minimum reflection loss value of −63.6 dB at 2.4 mm thickness. The maximum effective absorption bandwidth reached 6.67 GHz with thickness of only 1.9 mm. Compared with that of untreated-CF/PA6 composite, the thermal conductivities of MCTS4s-CF and MCTS5s-CF/PA6 composites increased by 45.2 % and 19.1 %. Simultaneously, the tensile strength of MCTS4s-CF/PA6 and MCTS5s-CF/PA6 composites increased by 19.5 % and 16.1 %. This new approach provided an effective way to realize multifunctional composites. Its low-cost, efficient and environmentally friendly process had great potential for large-scale production.

Design a WO3/Zn heterojunction for boosting the photodegradation of Favipiravir in aqueous solutions

ABSTRACT This study was aimed at designing a new type of heterojunction catalyst for the degradation of Favipiravir using visible light. Several WO3–ZnO nanocomposites with different Zn contents varying from 1 to 20 wt% were successfully developed via a simple one-step microwave irradiation procedure. Various analytical methods, including XRD, TEM, FESEM, EDAX, FTIR, and BET, BJH characterised the WO3-Zn catalysts. XRD pattern revealed that the small size of Zn ions is caused by the easy penetration of Zn ions into the WO3 crystalline with a monoclinic phase, which will lead to an increase in the surface area and a decrease in the size of the particles. According to FESEM and TEM images, nanocomposite particles had a non-uniform, irregular shape and a smaller particle size (20 to 40 nm). EDAX analysis related to WO3-Zn synthesised showed the O, W and Zn elements are 10%, 67%, and 23%, respectively. Response surface methodology using R software was used as a tool to optimise the amount of catalyst and Favipiravir concentration, time and pH. Effective parameters in the process, including the amount of catalyst in the range (0.5 to 2.5 g L−1), Favipiravir concentration in the range (1–10 mg L−1), time in the range (10–90 min) and pH in the range (4 to 9) were entered into the software and analysed. Under the optimised conditions of the parameters (pH, 4.96; amount of catalyst, 2 g L−1; amount of Favipiravir concentration, 10 mg L−1; and time, 60 min), the maximum removal efficiency (99.99%) was obtained. Also, 85.8% of the mineralisation of Favipiravir was found under the determined optimum conditions. Quenching experiments were conducted to investigate the reaction mechanism, the results showed that superoxide and hydroxyl oxidising radicals play an essential role in Favipiravir degradation..

One-pot radiolytically synthesized reduced graphene oxide-gold nanoparticles composites and exploration in energy storage

Graphene and its composites are of primary importance, particularly in the field of energy storage. Numerous bottom-up and top-down methods have been proposed in the literature to produce these materials with enhanced physicochemical properties. Recently, an innovative and green methodology was developed based on ionizing radiation, allowing the quantitative synthesis of graphene oxide-based materials. With the aim to extend this strategy for the preparation of hybrid nanomaterials, the objective of this work was the one-pot synthesis of nanocomposites composed of reduced graphene oxide – gold nanoparticles (rGO-AuNPs) via gamma ray-induced radiolytic reduction. UV–Vis Absorption Spectroscopy, Fourier Transform Infrared Spectroscopy, Raman Spectroscopy and X-ray Photoemission Spectroscopy were utilized to comprehensively evaluate the reduction degree of graphene oxide and the formation of gold nanoparticles. Atomic Force Microscopy and Scanning Electron Microscopy were employed to obtain the morphological and topographical information on synthesized nanocomposites. Thermal properties were investigated by Thermogravimetric Analysis and electrical properties were investigated using Cyclic Voltammetry and Potentiostatic Charge and Discharge method. The results demonstrated the successful reduction of graphene oxide and gold ions through the drastic transformation of oxygen-containing functional groups and the formation of gold nanoparticles. Electrical characterization results highlighted the excellent electrical properties of radiosynthesized rGO-AuNPs composites and their great potential for supercapacitance application.

Biological Effects of Green Synthesized Al-ZnO Nanoparticles Using Leaf Extract from Anisomeles indica (L.) Kuntze on Living Organisms.

The synthesis of Al-ZnO nanoparticles (NPs) was achieved using a green synthesis approach, utilizing leaf extract from Anisomeles indica (L.) in a straightforward co-precipitation method. The goal of this study was to investigate the production of Al-ZnO nanoparticles through the reduction and capping method utilizing Anisomeles indica (L.) leaf extract. The powder X-ray diffraction, UV spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy with EDAX analysis were used to analyze the nanoparticles. X-ray diffraction analysis confirmed the presence of spherical structures with an average grain size of 40 nm in diameter, while UV-visible spectroscopy revealed a prominent absorption peak at 360 nm. FTIR spectra demonstrated the presence of stretching vibrations associated with O-H, N-H, C=C, C-N, and C=O as well as C-Cl groups indicating their involvement in the reduction and stabilization of nanoparticles. SEM image revealed the presence of spongy, spherical, porous agglomerated nanoparticles, confirming the chemical composition of Al-ZnO nanoparticles through the use of the EDAX technique. Al-ZnO nanoparticles showed increased bactericidal activity against both Gram-positive and Gram-negative bacteria. The antioxidant property of the green synthesized Al-ZnO nanoparticles was confirmed by DPPH radical scavenging with an IC50 value of 23.52 indicating excellent antioxidant capability. Green synthesized Al-ZnO nanoparticles were shown in in vivo studies on HeLa cell lines to be effective for cancer treatment. Additionally, α-amylase inhibition assay and α-glucosidase inhibition assay demonstrated their potent anti-diabetic activities. Moving forward, the current methodology suggests that the presence of phenolic groups, flavonoids, and amines in Al-ZnO nanoparticles synthesized with Anisomeles indica (L.) extract exhibit significant promise for eliciting biological responses, including antioxidant and anti-diabetic effects, in the realms of biomedical and pharmaceutical applications.

Calcium-Mediated Cell Adhesion Enhancement-Based Antimetastasis and Synergistic Antitumor Therapy by Conjugated Polymer-Calcium Composite Nanoparticles.

Strengthening tumor cellular adhesion through regulating the concentration of extracellular Ca2+ is highly challenging and promising for antimetastasis. Herein, a pH-responsive conjugated polymer-calcium composite nanoparticle (PFV/CaCO3/PDA@PEG) is developed for calcium-mediated cell adhesion enhancement-based antimetastasis and reactive oxygen species (ROS)-triggered calcium overload and photodynamic therapy (PDT) synergistic tumor treatment. PFV/CaCO3/PDA@PEG is mainly equipped with conjugated poly(fluorene-co-vinylene) (PFV-COOH)-composited CaCO3 nanoparticles, which can be rapidly decomposed under the tumor acidic microenvironment, effectively releasing Ca2+ and the photosensitizer PFV-COOH. The high extracellular Ca2+ concentration facilitates the generation of dimers between two adjacent cadherin ectodomains, which greatly enhances cell-cell adhesion and suppresses tumor metastasis. The inhibition rates are 97 and 87% for highly metastatic tumor cells 4T1 and MCF-7, respectively. Such a well-designed nanoparticle also contributes to realizing PDT, mitochondrial dysfunction, and ROS-triggered Ca2+ overload synergistic therapy. Furthermore, PFV/CaCO3/PDA@PEG displayed superior in vivo inhibition of 4T1 tumor growth and demonstrated a marked antimetastatic effect by both intravenous and intratumoral injection modes. Thus, this study provides a powerful strategy for calcium-mediated metastasis inhibition for tumor therapy.

Highly operative removal of amoxicillin (AMX) from aqueous solution by MnFe2O4 nanoparticles and carboxy methyl cellulose (CMC) composite

In recent work, manganese ferrite (MnFe2O4) nanoparticles and manganese ferrite carboxy methyl cellulose (MnFe2O4/CMC) composite were synthesized using Salvadora persica extract (SPE). Characterization of green synthesized nanoparticles and composite was performed by different techniques such as FTIR, SEM, UV–visible spectroscopy, XRD, and EDX. These techniques evaluated the size, shape, composition, morphology, and crystallinity of bimetallic nanoparticles (BMNPs) and nano-composites (NCs). These techniques demonstrated the presence of oxygen with metals, 3.28 nm size of MnFe2O4 and CMC hump between the 22-26° and the spherical, cubic, and mostly irregular shape of MnFe2O4 nanoparticles and rougher surface of MnFe2O4/CMC composite. Nanoparticles and nanocomposites were utilized for the degradation of Amoxicillin (AMX). The maximum degradation of AMX occurred at optimum conditions such as adsorbent dosage (6 mg MnFe2O4, 2 mg MnFe2O4/CMC), pH (4,6) within 60 min at 5 mg/L initial AMX concentration. Results revealed that the catalytic activity of NCs (97 %) was more than BMNPs (93 %) which may be attributed to the incorporation of reduced Carboxy Methyl Cellulose (CMC). It reduced the e-hole recombination rate and enhanced the AMX degradation at ambient conditions. The nature of adsorption was illustrated by Langmuir and Freundlich models and results demonstrated that the Freundlich model followed more closely. Thermodynamics parameters described the endothermic and spontaneous nature of the adsorption process, negative Gibbs energy variation, and positive entropy and enthalpy change. The recovery and reusability of BMNPs and NCs were investigated and concluded that MnFe2O4 and NCs can be used many times for the AMX adsorption process.

Multifunctional endogenous small molecule-derived polymer composite nanoparticles for the treatment of acute sepsis therapy

Multifunctional endogenous small molecule-derived polymer composite nanoparticles for the treatment of acute sepsis therapy

A critical review on synthesis and application aspect of venturing the thermophysical properties of hybrid nanofluid for enhanced heat transfer processes

Recently, nanofluids (NFs) have gathered significant attention among researchers due to their varied properties, which can be made per the requirements. NFs, created by infusing nanoparticles into a base-fluid, enhance their fundamental properties. A hybrid nanofluid (HNF) is a nanofluid (NF) containing different types of nanoparticles, and it is being studied for its customizable properties. Recently, researchers delved into the applications regarding HNFs, particularly in cases relating to heat transfer (HT). This study analyzes HNFs’ preparation methods and thermophysical properties, giving more importance to their applications in HT, including heat-exchange, solar thermal, and cooling systems. Considering stability, the two-step synthesis method is preferred over the single-step method. Multiple research efforts have led to the development of a fluid that possesses superior HT capabilities compared to the base-fluid. However, while bettering HT, an increase in volume concentration (VC) also raised challenges such as increased viscosity and pressure drop, particularly in porous media, necessitating additional pumping power. The use of turbulators and other configurations, along with HNF in systems like parabolic trough solar collectors (PTSCs), enhances solar thermal systems (STSs) by improving their HT capabilities. An advantageous use of EG-based multiwalled carbon nanotubes (MWCNTs) NF in solar collectors (SCs) is their ability to increase thermal efficiency and decrease carbon dioxide emissions, making them an attractive choice for use in SCs. Researchers face significant challenges in determining the ideal composition and concentration of nanoparticles in HNFs to attain optimal HT without causing excessive viscosity that could impede practical usability. Specifically, this study examines the distinctive thermophysical characteristics of HNFs that substantially improve their efficacy in HT applications.

Photovoltaic panel cooling with new composite of phase change materials and hierarchical nanoparticles

In this research, the use of a new type of phase change materials (PCM) and hierarchical nanoparticles is discussed to improve the electrical and thermal efficiency of PV panels. TiO2/CuO hierarchical nanoparticles are synthesized by hydrothermal method, and PCMs containing nanoparticles (2.5–10%wt) are prepared, and then experiments are performed in indoor conditions under solar simulator light. The PV panel with a maximum nominal power of 30W is used. The new PCM is made from a mixture of lauryl alcohol and beeswax (LABW). A spiral heat exchanger is placed in the PCM container, in which the flow rate of cool water is variable (m˙ = 0.002–0.01 kg s−1). Firstly, the temperature and voltage-current changes of the PV panel with time are investigated without using PCMs as a reference case, and in steady-state conditions, the temperature and output power values are 67.34 °C and 22.33W. The use of LABW compared to pure beeswax leads to a significant decrease in the PV panel temperature and as a result, an increase in its electrical and thermal efficiency. Also, adding nanoparticles to PCMs from 2.5 % to 7.5 %wt due to the improvement of their thermal conductivity and increasing the heat storage rate of the PV panel leads to an increase in its electrical and thermal efficiency. There is no significant change to decrease the temperature and increase the production capacity of PV panels by increasing the percentage of nanoparticles from 7.5 % to 10%wt. The maximum production power, electrical and thermal efficiency of the PV panel at a flow rate of 0.01 kg s−1, 10%wt of nanoparticles, and a radiation intensity of 1000 W m−2 are 28.92 W, 12.55 %, and 76.67 %, respectively.

Fabrication and characterization of novel TGase-mediated glycosylated whey protein isolate nanoparticles for curcumin delivery

The aim of this study was to fabricate novel transglutaminase (TGase)-mediated glycosylated whey protein isolate (WPI) nanoparticles for the encapsulation and delivery of curcumin. The influences of glycosylation on the physiochemical properties, stability, bioavailability, and antioxidant properties of WPI nanoparticles loaded with curcumin were investigated. Composite nanoparticles exhibited uniform distribution and small particle sizes. The main driving forces for the formation of curcumin nanoparticles were electrostatic interactions, hydrogen bonding, and hydrophobic interactions. The encapsulation and loading efficiency of curcumin after TGase-type glycosylation were significantly increased in comparison to WPI-curcumin nanoparticles. Glycosylated WPI-curcumin nanoparticles had stronger antioxidant properties and stability to resist external environmental changes than WPI-curcumin nanoparticles. In addition, glycosylated WPI-curcumin nanoparticles showed a controlled release and enhanced curcumin bioavailability in vitro gastrointestinal digestion. This study provides novel insights for self-assembled glycosylated protein nanoparticles as delivery systems for protecting hydrophobic nutrients.

Nanoparticles of dust as an emerging contaminant in urban environments.

Due to very high mobility in the environment and penetration ability into living organisms, nanoparticles (NPs) of urban dust pose a potential threat to human health and urban ecosystems. Currently, data on the chemical composition of NPs of urban dust, their fate in the environment, and corresponding risks are rather limited. In the present work, NPs of deposited urban dust have been comprehensively studied for the first time; NPs isolated from 78 samples of dust collected in Moscow, the largest megacity in Europe, being taken as example. The elemental composition, potential sources as well as environmental, ecological, and health risks of NPs of urban dust are assessed. It is found that dust NPs are extremely enriched by Cu, Hg, Zn, Mo, Sb, and Pb, and can serve as their carrier in urban environments. No regularities in the spatial distribution of elements have been found, probably, due to high mobility of dust NPs. High ecological and health risks caused by dust NPs are demonstrated. Source apportionment study has evaluated one natural and two anthropogenic sources of elements in NPs of urban dust; the contribution of natural and anthropogenic sources being comparable. It is also shown that dust NPs may be considered as an important carrier of trace elements in urban aquatic systems. Additionally, the risks associated with NPs and bulk samples of dust have been compared. The observed risks associated with NPs are significantly higher.

Characterization of sodium alginate film containing zein-Arabic gum nanoparticles encapsulated with oregano essential oil for chilled pork packaging

Chilled pork retains most of its nutrients but is prone to deterioration during the production-to-consumption process. To address this issue this study aimed to develop zein-Arabic gum composite nanoparticles loaded with oregano essential oil (ZAG-OEO) and incorporate them into sodium alginate films to enhance the freshness and shelf life of chilled pork. Sodium alginate, known for its excellent film-forming properties, was selected as the matrix to prepare ZAG-OEO-containing sodium alginate films (SA-ZAG-OEO). The results revealed that the tensile strength and elongation at break of the prepared films were 47.73 ± 2.15 MPa and 6.27 ± 0.21 %, respectively, at a 2.5 % nanoparticle concentration. The water contact angle of the films incorporating nanoparticles reached 81.5 ± 1.95°. The incorporation of nanoparticles enhanced the thermal stability and antibacterial activity of the films. The prepared films were utilized for the storage of chilled pork, and the quality changes were analyzed. The results demonstrate that SA-ZAG-OEO films inhibit microbial growth and lipid oxidation, thereby delaying pork spoilage. This study offers new insights into extending the shelf life of chilled pork and developing advanced meat preservation methods for the future development of the meat industry.

Enhanced Electrocatalytic Performance of the FePt/PPy-C Composite toward Methanol Oxidation.

A novel FePt/PPy-C composite nanomaterial has been designed and investigated as a methanol oxidation reaction (MOR) electrocatalyst. The FePt nanoparticles with an average diameter of about 3 nm have been prepared by the co-reduction method and then loaded onto the PPy-C composite support. The electrocatalytic performance is affected by the composition of the FePt nanoparticles. The experimental results indicated that the Fe1.5Pt1/PPy-C catalyst exhibited excellent catalytic activity and stability for MOR, with mass activity and specific activity of 1.76 A mgPt-1 and 2.71 mA cm-2, respectively, which are 5.18 and 4.60 times higher than that of the commercial Pt/C catalyst. Density functional theory (DFT) has been employed to simulate the electrical structures of catalyst supports, and the mechanism of the methanol oxidation process has been further analyzed. The heterojunctions of the PPy-C interface could accelerate the electron migration from the electrocatalytic center to the electrodes. The possibility of methanol oxidation has been improved effectively, which can be confirmed by the d-band center and CO adsorption energy on FePt nanoparticles in the DFT calculation results.

Effect of Shell Cover Color on Solar Absorptance and Environmental Heating of Cricket Helmets: A Pilot Study

The objective of this pilot study was to quantify and describe the effect of shell cover color on solar absorptance, a1 (%; mean ± SD) and the temperature of the cricket helmet shell covers, Thsc (°C; mean ± SD) during exposure to a hot outdoor environment (WBGT 32.5 ± 1.9 °C; ACSM Heat Index Black; Extreme Danger STOP). We measured and recorded a1 in yellow, red and black cricket helmets using a micro-solarimeter. Thermographic imaging was used to quantify differential Thsc . Variations in shell cover color had a statistically significant (p<0.0002) 2-fold effect on a1 . At the end of 30-minute trials, variations in color and a1 resulted in 3.6 to 6.0 °C difference in Thsc between helmets. Although speculative, the color of cricket helmet shell covers may have a functionally significant effect of exertional heat illnesses, EHIs (ranging from dehydration to heat stroke). Incorporating reflective nanocomposites particles into the material used in the construction of the Lycra® shell covers and XENOY™ shells may facilitate passive cooling of cricket helmets and ultimately reduce EHIs.

Biomimetic Calcium Phosphate Nanoparticles: Biomineralization Models and Precursors for Composite Materials.

The formation of calcium phosphate under the control of water-soluble polymers is important for understanding bone growth in living organisms. These experiments also have spin-offs in the creation of composite materials, including for regenerative medicine applications. The formation of calcium phosphate (hydroxyapatite) from calcium chloride and diammonium phosphate was studied in the presence of polymers containing carboxyl, amine, and imidazole groups. Depending on the polymer composition, solid products and stable dispersions of positively or negatively charged nanoparticles were obtained. Oppositely charged nanoparticles can interact with each other to form a macroporous composite material, which holds promise as a filler for bone defects. The formation of a calcium phosphate layer around a living cell (dinoflagellate Gymnodinium corollarium A. M. Sundström, Kremp et Daugbjerg) using positive composite nanoparticles is a one-step approach to cell mineralization.

Hydrogen evolution from NaBH4 using novel Ni/Pt nanoparticles decorated on a niobium-based composite

The niobium-based nanocomposite (Nb-CP), inspired by MOF-based synthesis, was developed utilizing the ligands 4-benzenedicarboxylic acid (BDC) and 1,3,5-benzenetricarboxylic acid (BTC). This material was decorated with bimetallic nanoparticles (Ni2/Pt8 NPs-Nb-CP) and applied for the first time for hydrogen evolution from sodium borohydride (NaBH4). Characterization results indicated successful synthesis. The FT-IR analysis revealed the presence of functional groups such as -C-H, –CO, and -O-H from ligands in the composite. Thermogravimetric analysis confirmed the thermal stability of the niobium composite (Nb-CP). Through X-ray diffraction (XRD), peaks associated with sodium niobate were detected. Additionally, the material was functionalized with bimetallic Ni/Pt nanoparticles, whose presence was also identified by XRD. The cubic morphology of the material was observed, with the decoration of bimetallic nanoparticles (Ni2/Pt8 NPs-Nb-CP) with an average size of 7.80 ± 0.10 nm, uniformly distributed in Nb-CP. The catalytic performance of the material was evaluated in hydrogen evolution from NaBH4. Various reaction parameters were investigated, such as nanoparticle composition, variation in NaBH4 concentration, catalyst dose, NaOH concentration, and temperature. Remarkably, the material exhibited a hydrogen generation rate (HGR) of 1782 mL min−1 g−1cat and an activation energy of 23.1 kJ mol−1. Furthermore, it demonstrated efficiency close to 100% over 16 consecutive reaction cycles, indicating its promising stability and reusability. This study highlights the potential of Ni2/Pt8 NPs-Nb-CP as an efficient and durable catalyst for hydrogen production through borohydride hydrolysis, providing insights into the design and application of advanced heterogeneous catalytic materials.

Hierarchically decorated ZnO/CoOx nanoparticles on carbon fabric for high energy–density and flexible supercapacitors

Exploring the electrochemical performance of metal/metal oxide nanoparticle composites is vital for enhancing the charge storage capability of supercapacitors. Herein, electrodes coated with ZnO/CoOx are fabricated by soaking cotton fabric seeded with 2-methylimidiazole in an ethylene glycol–based solution containing Zn and Co salts. The use of cotton fabric can reduce textile industrial waste while achieving high capacitance and sustainable energy for wearable electronics. In addition, the three-dimensional network of conductive flexible carbon derived from cotton fabric facilitates rapid ion transport kinetics at interlayers. The concentrations of Zn and Co salts are varied to produce ZnO/CoOx samples and determine the optimal salt ratio for superior electrochemical performance. The optimal sample exhibits a capacitance of 1.95 F cm−2 at 5 mA cm−2 and an energy density of 725 μWh·cm−2 over a wide potential window of 1.6 V. The long-term stability test results of the symmetric cells indicate 94 % capacitance retention after 12,000 charge–discharge cycles, emphasizing the advantages of mixed metallic oxides with cellulose-derived carbon fabric for supercapacitor electrodes. This study offers valuable insights into the fabrication of high-performance, flexible, and binder-free supercapacitor electrodes as a scalable alternative for practical applications.

Three-dimensional porous polycaprolactone/chitosan/bioactive glass scaffold for bone tissue engineering

Three-dimensional (3D) porous scaffolds based on polycaprolactone (PCL)/chitosan (CS)/bioactive glass (BG) nanoparticle composites were fabricated by the freeze-drying technique for bone tissue engineering. The physiochemical properties of the developed PCL/CS/BG scaffolds were studied using FTIR, XRD, EDX and SEM. Furthermore, the swelling degree, porosity, water retention ability, compression strength, in vitro biodegradation, bioactivity and biocompatibility of the scaffolds were examined. The PCL/CS/BG scaffolds with 4 wt. % of BG content presented adequate pore size (106 μm), porosity (156%), water swelling degree (128%), water retention ability (179%), compressive strength (3.7 MPa) and controlled degradation behavior, which could be ideal for bone tissue engineering. The PCL/CS/BG composite scaffolds showed good antimicrobial activity against both test bacteria and fungi. The MTT assay demonstrated the biocompatibility of PCL/CS/BG scaffolds against C3H10T1/2 cell line. The Alizarin red staining assay confirmed the osteogenic activity of the PCL/CS/BG scaffolds.

Sonochemical deposition of gold nano-shells on suspended polymeric spheres

Metal nanoparticles have drawn great interest due to their unique properties for applications in the fields of catalysis, biomedicine and environmental science depending on the architecture of the metal nanoparticle composites. Amongst different designing routes, the chemical template deposition offers great flexibility in terms of the template selection and interfacial interactions, giving rise to controllable designs. In order to control over nanoparticle size distribution and deposition efficiency, a sonochemical approach has been systematically followed in this study. Key parameters of the ultrasound-assisted deposition procedures during the seeding step to synthesise gold nanoparticle-coated poly(styrene) beads were investigated. The impact of the solution pH and the ultrasonic frequency on the template deposition was examined at 139, 300, 500 and 1000 kHz. The results, monitored by transmission electron spectroscopic imaging, show that the highest gold deposition was achieved at 300 kHz, revealing the mechanistic details of the nucleation-crystal growth behaviour as a function of ultrasonic frequency and reaction time. In addition, the concentration ratio between gold ions and poly(styrene) beads was varied. The highest deposition coverage and smallest particle size were reached at 0.05 mM and 2.5 mg, respectively. The proposed mechanism of the MNPs formation and deposition behaviour were then discussed based on the tested parameters.