Next Nanotechnology最新文献

A luminescent trimetiallic nanocluster (NCs) stabilized by BSA protein (AuAgCd-BSA) was synthesized along with its mono and bimetallic counterparts (Au-BSA and AuAg-BSA). The detail characterization and comparative luminescence sensing performance for narcotic drugs and psychotropic substance (amphetamine, morphine) were performed for these three clusters. It was revealed that the trimetallic cluster can detect amphetamine and morphine drugs through turn on luminescence response. The calculated binding constants are found to be K_a = 5.86× 10³ M⁻¹ for Amphetamine and 3.75× 10³ M⁻¹ for Morphine by using Benesi-Hildebrand equation. The trimetallic cluster also showed selective turn off luminescence response in presence of mercury (Hg²⁺) ions. The origin of the enhanced PL responses in presence of amphetamine and morphine was further investigated by exploring the PL lifetime decay studies, which reveals that larger excited state lifetime (in μs timescale) value of pristine cluster remain unchanged upon incremental addition of drugs leading to longer interaction time with the analytes. Thus, the present work undoubtedly establishes the superior drug sensing behaviour of AuAgCd-BSA tri-metallic NCs as compared to its mono-metallic and bi-metallic counterparts and open further emphasis on exploring luminescence-based sensing of narcotic drugs which has great forensic relevance.

Zirconia has become a popular choice for indirect restorations; however, adhesion to this material remains a challenge. The present study aimed to evaluate surface characteristics and bond strength to tetragonal Y-TZP and cubic Y-PSZ zirconia submitted to experimental surface treatments. Specimens of Y-TZP (T) and Y-PSZ (P) were prepared and divided into groups: Tf-A) thin TiO₂ film functionalized with 3-(aminopropyl)trimethoxysilane (APTMS); Tf) thin TiO₂ film; MNt-A) manual application of TiO₂ nanotubes with APTMS; MNt) manual application of TiO₂ nanotubes; VNt-A) vacuum application of TiO₂ nanotubes with APTMS; VNt) vacuum application of TiO₂ nanotubes; C) control with Al₂O₃ sandblasting. Characterization with x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) was done. Bond strength was evaluated by microshear bond strength (µSBS). Data were analyzed by two-way ANOVA and Tukey’s HSD tests (α = 0.05). XPS showed signals for elements O 1 s, Ti 2p, and Zr 3d 5/2. In addition, high-resolution demonstrated Ti-O-Si and Zr-O-Si bonding for treatments with TiO₂ and APTMS for T-Tf-A/P-Tf-A. SEM presented a homogeneous film for T-Tf/T-Tf-A/P-Tf/P-Tf-A and cluster formations for all nanotube groups. Control groups for both Y-TZP and Y-PSZ showed clear surfaces. No differences of µSBS were seen between experimental surface treatments and the controls, except for T-MNt-A/T-VNt-A/P-MNt-A/P-VNt-A, which showed the lowest mean µSBS and highest incidence of pre-test failures. Surface treatments with TiO₂ nanostructures were effective in modifying the surface of both zirconia materials evaluated, providing strong covalent bonds, changes to the surface topology, and shear bond strength comparable to conventional sandblasting protocols.

Caffeic acid, a potent polyphenol belonging to the hydroxycinnamic acid derivative class, was utilized in the synthesis of silver nanoparticles (AgNPs) at ambient temperature. The resultant conjugates underwent comprehensive characterization employing various analytical techniques, including UV–visible spectroscopy, FTIR, RAMAN spectroscopy, dynamic light scattering (DLS) for size and zeta potential analysis, atomic force microscopy (AFM), and scanning electron microscopy (SEM). Through these analyses, the morphological characteristics of the synthesized nanoparticles were elucidated, providing valuable insights into their structural properties. Subsequently, the cytotoxic effects of the caffeic acid-synthesized silver nanoparticles were assessed against A549 cells over a 48-h period by MTT assay. Remarkably, these nanoparticles exhibited significant toxicity towards the cells, with inhibitory effects observed at concentrations of 141 μg/ml for CA AgNPs. This underscores their potential as potent agents against cancer cells. Furthermore, the profound significance of caffeic acid-synthesized silver nanoparticles was evaluated specifically against A549 lung cancer cells. This was corroborated through cell cycle analysis, which demonstrated the potent anticancer activity of the caffeic acid-synthesized silver nanoparticles. Such findings suggest promising prospects for their utilization in diverse cancer treatment modalities. Overall, the successful synthesis and characterization of caffeic acid-synthesized silver nanoparticles underscore their potential as potent agents against cancer, particularly in combating A549 lung cancer cells. Further research and exploration into their mechanisms of action and potential synergistic effects with existing anticancer therapies could unveil additional avenues for their clinical translation and utilization in cancer management.

Here, we describe the phytosynthesis of nickel nanoparticles (NiNPs) utilizing an extract from the leaves of Azadirachta indica as a reducing and capping agent. The optimal conditions for synthesizing stable NiNPs were pH 6.8, temperature 70°C, and 5 % leaf extract and [NiNO₃.6H₂O] = 1.0×10⁻³ mol dm⁻³. The X-ray diffraction (XRD) analysis revealed a face-centered cubic crystalline structure, and the Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM) analyses verified a triangular form with particles ranging in size from 7 to 18 nm. The study examined the impact of reactant concentrations, reaction temperature, and solution pH on the nickel nanoparticle fabrication method. The following are the ideal parameters for synthesis: 5 % leaf extract, pH = 6.8, temperature = 70 °C, and [NiNO₃.6H₂O] = 1.0×10⁻³ mol dm⁻³. Plant biomolecules induce the reduction of nickel ions to NiNPs and function as a capping and stabilizing agent, as confirmed by the FTIR technique. The findings indicated that the synthesis of NiNPs from A. indica leaf extracts are safe technology and may have significant impacts on the industrial synthesis of metallic nanoparticles.

The increasing demand for renewable energy has stimulated significant advancements in the photovoltaic technology (PV), with perovskite solar cells (PSCs) emerging as leading alternatives because of their impressive efficiency and versatile characteristics. Nevertheless, conventional lead-based PSCs face critical challenges such as environmental instability, lead toxicity, and limited durability, which hinder their broader commercial applications. Chalcogenide-based perovskites, on the other hand have been advanced as promising options, offering improved stability, less toxic compositions, and the potential for more cost-effective, scalable production. This review thoroughly examines the progress made in chalcogenide perovskite research, highlighting their tunable bandgaps for diverse applications, superior charge transport properties, and resilience against advanced weathering conditions such as moisture, oxygen, and UV light. The graphene-like characteristics of certain chalcogenide perovskites, which contribute to their high charge mobility and flexibility, make them strong candidates for the next-generation PV technologies. Furthermore, this work explores the expanding potential for indoor applications of these materials, including their integration into flexible indoor PSCs and other optoelectronic devices designed for controlled environments. Also, various synthesis and optimization strategies, such as advanced deposition techniques, precise doping methods, and innovative interface and additive engineering are presented, aimed at enhancing the PV performance of these materials. Accordingly, this review bridges the gap between fundamental research and practical applications, outlining a strategic direction for developing chalcogenide-based PSCs and optoelectronic devices that meet the global energy demand while advancing sustainability and environmental safety.

During the COVID-19 pandemic, the mandatory use of multiple surgical masks or N95 respirators in public raised concerns about potential health issues associated with the increased breathing force needed to maintain the breathing cycle. To address these concerns, we conducted a comprehensive study investigating the transportation and filtering mechanisms of heterogeneous nanoparticles and virus-like particles through surgical masks and N95 respirators. Our multifaceted approach combined in vitro experiments utilising aerosol spray paints containing nanoparticles and in vivo validation on human volunteer inhaling city air. We employed scanning electron microscopy and transmission electron microscopy to analyse the distribution of nanoparticles across various mask layers and pristine silicon substrates placed on human skin. In addition, we provide analytical insights into the pressure distribution and fluid velocity profiles within the complex polymer fibre network of the masks. Our findings remarkably revealed that both single surgical masks and N95 respirators exhibited similar nanofluidic performance in filtering colloidal and jet-stream nanoparticles in the air. These results have significant implications for policymakers in developing regulations to manage airborne pandemics and air pollution control, ultimately enhancing public health and safety during respiratory health crises.

This study utilized blue-light epitaxial wafers and employed semiconductor processes such as maskless laser writing, dry etching, wet etching, passivation layer deposition, electron beam evaporation, and ion implantation to fabricate micro-light emitting diode (μLED) arrays with different pixel sizes but the same emitting area (900 μm²). The μLED arrays with single pixel sizes of 5 μm, 10 μm, and 15 μm were fabricated, with array numbers of 6×6, 3×3, and 2×2, respectively. This study proposes etching the material in the channel region while retaining a certain width for implantation, known as the sidewall ion implantation process, aiming to achieve better insulation characteristics by using ion implantation technology to insulate the sidewall regions. It involves ion bombardment of the defect areas generated after plasma etching and the use of a passivation layer for protection. The isolation characteristics of μLED arrays processed by sidewall implantation exhibited better electrical isolation than those of μLED arrays processed only by plasma. The light output power, external quantum efficiency, and wall-plug efficiency were all superior for the sidewall implantation process when the device was miniaturized to 5 μm. Overall, the sidewall implantation process combined with plasma dry etching effectively improved the light output characteristics, with the enhancement ratio increasing as the device was miniaturized.

Nano bacterial cellulose (NBC) being a biopolymer has unique physical and chemical properties with high biocompatibility. It is pure cellulose with nanometer size, produced by certain group of bacteria. Its properties can be further improved by combining with poly(vinyl alcohol) (PVA), which is a fascinating polymer soluble in water and biocompatible. Composite films of PVA and NBC were prepared by solution casting method. Composite films of PVA-NBC (0,1,2,3,4,5 %) were tested for major packaging properties like water vapor transmission rate, swelling measurement, film solubility and moisture retention capacity. Among all concentration films, film with 5 % NBC- PVA showed better results for all the tests. Films were also checked for antimicrobial properties against spoilage-causing bacteria and fungi. Further, the films were applied to study the shelf life in the Mitli Banana (Musa sp.) followed by Organoleptic evaluation during storage. Results showed that the banana packed with 5 % NBC- PVA film has retained maximum acceptable characters than other packages.

The work focuses on the development of a hybrid nanofluid (NF) comprising zinc oxide-graphene (ZG) to address heat transfer (HT) limitations in thermal systems. The study employs a highly sensitive mode-mismatched dual-beam thermal lens (MDTL) method to analyze the lattice dislocation-induced thermal diffusivity (D) modifications of the hybrid NF. The hybrid composite (HC) is synthesized by solid-state mixing and annealing of ZG. The formation of ZG hybrid composites is revealed through X-ray diffraction (XRD), Fourier transform infrared, X-ray photoelectron, and Raman spectroscopic analyses. The structural dislocations present in the HC are understood from XRD and Raman analyses. Ultraviolet-visible and photoluminescence spectroscopic studies revealed the optical properties of the samples. The MDTL study is carried out by preparing the NFs of the synthesized samples in the base fluid, ethylene glycol (EG), and reveals the impact of crystallite defects on the thermal characteristics of the synthesized composites. Thus, the study suggests the potential capability of ZG composites in tuning the thermal behaviour of EG for HT applications.

NiO nanoparticles were synthesized using jasmine flower and orange peel. The transition from cubic to rhombohedral phase was observed with peak splitting in the XRD patterns as the annealing temperature increased. Differences in the annealing environment resulted in particles with different crystallite sizes and amounts of nickel vacancy, directly impacting their magnetic properties. Notably, particles below 30 nm exhibited weak ferromagnetism, while those above 30 nm showed antiferromagnetic properties. Moreover, the power of the laser was tuned to 5 mW to achieve the disappearance of the 2 M peak. A key highlight of this work is the identification of the transverse acoustic phonon mode and the splitting of the transverse optical (TO) mode in NiO.