Mean Diameter Of Nanoparticles Research Articles

An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter.

Here, we demonstrate a detail protocol for the preparation of nanomaterials-embedded composite membranes and its application to the efficient and ion-selective removal of radioactive iodines. By using citrate-stabilized gold nanoparticles (mean diameter: 13 nm) and cellulose acetate membranes, gold nanoparticle-embedded cellulose acetate membranes (Au-CAM) have easily been fabricated. The nano-adsorbents on Au-CAM were highly stable in the presence of high concentration of inorganic salts and organic molecules. The iodide ions in aqueous solutions could rapidly be captured by this engineered membrane. Through a filtration process using an Au-CAM containing filter unit, excellent removal efficiency (>99%) as well as ion-selective desalination result was achieved in a short time. Moreover, Au-CAM provided good reusability without significant decrease of its performances. These results suggested that the present technology using the engineered hybrid membrane will be a promising process for the large-scale decontamination of radioactive iodine from liquid wastes.

Cold Atmospheric Plasma Annealing of Plasmonic Silver Nanoparticles

Silver nanoparticles deposited on quartz substrate are annealed by cold atmospheric plasma jet to tailor the surface plasmon resonance (SPR) of silver nanoparticles. SPR is the unique optical property which arises due to the interaction of electromagnetic waves with the conduction electrons on the metal nanoparticle surface. The collective oscillations of these conduction electrons at specific EM wavelengths leads to strong scattering and absorption. For silver nanoparticles (AgNPs), the SPR occurs in UV-visible region and therefore AgNPs are used in various applications including solar energy harvesting, light emitting diodes, printed optoelectronic devices, and surface enhanced Raman scattering(SERS). The SPR absorbance peak strongly depends on the size, shape and assembly of the metal nanoparticles. The SPR absorbance peak can be tailored by thermal annealing of AgNPs. The annealing or sintering leads to change in mean diameter of nanoparticle due to agglomeration or reduction in the outside oxide layer of nanoparticles and therefore either red or blue shift in SPR is observed. However, thermal annealing is not always desirable, especially for the flexible polymer substrates. In the present work, we demonstrate the efficacy of cold atmospheric plasma annealing to achieve desired thermal annealing effects at room temperature. Silver nanoparticle films were deposited on the quartz substrate by injecting NP aerosol in the flowing argon gas. As deposited AgNP films were annealed by low temperature atmospheric plasma jet for 5 mins, 10 mins and 15 mins. Fig 1(a) shows the optical absorption spectra for un-annealed as well as annealed AgNP films. For un-annealed sample we observed the SPR absorbance peak at 426 nm. This peak was blue shifted by 14 nm, 36 nm and 62 nm for plasma annealed films for 5 min, 10 min and 15 min respectively. The AgNP films were also annealed using rapid thermal processing (RTP) at 100°C, 250°C, and 400°C for 5 min, 10 min and 15min. For all the temperatures, SPR peaks were blue shifted and for 400°C (corresponding the thermal energy of 58 meV) the blue shift values coincided with the values observed for plasma annealed AgNP films at room temperature. The plasma treated AgNP films were used as SERS substrates for Raman scattering studies of cortisol biomolecule. The Raman scattering signal from plasma annealed AgNP film was two times higher than that of bare quartz substrate. Figure 1

Preparation of a Pt/NiFe layered double hydroxide/reduced graphene oxide composite as an electrocatalyst for methanol oxidation

Reduced graphene oxide (RGO) has been shown to be an excellent support for Pt-based nanoparticles due to its large surface area and abundant chemical functional groups/defects available for anchoring. However, the restacking that occurs during the reduction of graphene oxide precludes its independent application. A variety of methods have been utilized to solve this problem, including surface modification, element doping, and insertion of separator. A novel NiFe layered double hydroxide/reduced graphene oxide (NiFe-LDH/RGO) composite was prepared by a facile one-pot solvothermal process using LDH as an effective separator, with subsequent Pt nanoparticles deposition via electrodeposition. The activity of this Pt/NiFe-LDH/RGO catalyst towards the methanol oxidation reaction (MOR) in alkaline media was studied by cyclic voltammetry (CV), and its stability was investigated by chronoamperometry (CA). The morphology was characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and scanning electron microscopy (SEM). The structure was determined by examining X-ray diffraction (XRD) patterns. The resulting Pt/Ni-Fe LDH/RGO electrocatalyst exhibits higher peak current density (949.3 mA mg−1), larger electrochemically active surface area (24.6 m2 g−1Pt) and better stability for methanol oxidation than its RGO-free counterpart (512.3 mA mg−1, 17.7 m2 g−1Pt). Moreover, the Pt nanoparticles mean diameter of Pt/NiFe-LDH/RGO electrocatalyst is 6.27 nm, which is much smaller than other contrast.

The use of chitosan/PLA nano-fibers by emulsion eletrospinning for periodontal tissue engineering

Objective: In this study, nanofibrous scaffolds base on pure polylactic acid (PLA) and chitosan/PLA blends were fabricated by emulsion eletrospinning. By modulating their mechanical and biological properties, cell-compatible and biodegradable scaffolds were developed for periodontal bone regeneration.Methods: Pure PLA and different weight ratios of chitosan nano-particle/PLA nano-fibers were fabricated by emulsion eletrospinning. Scanning electron microscope (SEM) was performed to observe the morphology of nano-fibers. Mechanical properties of nano-fibers were tested by single fiber strength tester. Hydrophilic/hydrophobic nature of the nano-fibers was observed by stereomicroscope. In vitro degradation was also tested. Cells were seeded on nano-fibers scaffolds. Changes in cell adhesion, proliferation and osteogenic differentiation were tested by MTT assay and Alizarin Red S staining. Reverse transcription-polymerase chain reaction (RT-PCR) assay was used to evaluate the expression of (Toll-like receptor 4) TLR4, IL-6, IL-8, IL-1β, OPG, RUNX2 mRNA.Results: It is shown that the mean diameter of nano-fibers is about 200 nm. The mean diameter of chitosan nano-particles is about 50 nm. The combination of chitosan nano-particles enhanced the mechanical properties of pure PLA nano-fibers. By adding a certain amount of chitosan nano-particles, it promoted cell adhesion. It also promoted the osteogenic differentiation of bone marrow stem cells (BMSCs) by elevating the expression of osteogenic marker genes such as BSP, Ocn, collagen I, and OPN and enhanced ECM mineralization. Nonetheless, it caused higher expression of inflammatory mediators and TLR4 of human periodontal ligament cells (hPDLCs).Conclusion: The combination of chitosan nano-particles enhanced the mechanical properties of pure PLA nano-fibers and increased its hydrophilicity. Pure PLA nano-fibers scaffold facilitated BMSCs proliferation. Adding an appropriate amount of chitosan nano-particles may promote its properties of cell proliferation and osteogenic differentiation. The higher expression of inflammatory mediators caused by nano-fibers may be regulated via TLR4 pathway.

Preparation and wear assessment of ultrasonic electrodeposited Ni–TiN thin films

In this study, pure Ni and Ni–TiN thin films were prefabricated from a reformative Watt nickel bath through ultrasonic electrodeposition (UE) under pulse current (PC) condition. The effects of ultrasonic intensity on surface morphology, microstructure and phase composition were evaluated through scanning electron microscopy (SEM), scanning probe microscopy (SPM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The Vickers hardness, the friction coefficient and the wear resistance of Ni and Ni–TiN thin films were also estimated. All SEM, SPM, and TEM results demonstrated that the Ni-TiN thin film obtained at the ultrasonic intensity of 30 W/cm2 had a fine, smooth and homogeneous surface morphology. The root-mean-square roughness (Rms) and arithmetic mean roughness (Ra) of the film with a surface area of 4.096 µm2 were 36.813 nm and 22.836 nm, respectively. Also, the mean diameters of Ni grains and TiN nanoparticles were approximately 46.7 nm and 23.2 nm, respectively. The XRD analysis indicated that the XRD patterns of the films prepared with different plating parameters had the same diffraction angle with the Ni phase except the diffraction intensity. Microhardness tests exhibited that the Ni film displayed the minimum microhardness value of 38.6 HV. Moreover, the Ni-TiN film obtained at the ultrasonic intensity of 30 W/cm2 acquired the maximum microhardness value of 912.1 HV. The wear behavior assessment demonstrated that the Ni-TiN film prefabricated at the ultrasonic intensity of 30 W/cm2 sustained the least weight loss, while the mean friction coefficient was approximately 0.39, thereby displaying the best wear resistance.

Cytotoxicity assay of plant-mediated synthesized iron oxide nanoparticles using Juglans regia green husk extract

Synthesis of iron oxide nanoparticles has attracted increasing interest due to their importance in biomedical and technological applications. To investigate the ability of Juglans regia (J. regia) green husk extract in iron oxide nanoparticles size control, they were synthesized through co-precipitation method with J. regia extract and without it. For both tests, other experimental conditions were same. According to High-resolution transmission electron microscopy, the mean diameter and standard deviation of iron oxide nanoparticles and J. regia/iron oxide nanoparticles synthesized using co-precipitation method were 12.60 ± 2.87 and 5.77 ± 1.66 nm respectively. These results showed that J. regia/iron oxide nanoparticles synthesized using extract have a smaller size than nanoparticles fabricated by co-precipitation method; moreover, green husk extract plays the main role as size control. The obtained results of Powder X-ray diffraction (PXRD), High resolution transmission electron microscopy (HR-TEM), Field emission scanning electron microscopy (FESEM), and Energy dispersive X-ray (EDX) are in good agreement with each other and confirm the high purity of fabricated magnetic nanoparticles using J. regia extract. Vibrating sample magnetometer (VSM) revealed that the J. regia/iron oxide nanoparticles due to their proper magnetic properties have high saturation magnetization and low coercivity. According to FTIR spectrum, the J. regia would be coated on the iron oxide nanoparticles surface in a successful manner. The non-toxic effect of J. regia/iron oxide nanoparticles concentration below 1000 µg/ml was observed in the studies of in vitro cytotoxicity on normal and cancerous cell lines, respectively. The dose-dependent toxicity made it a suitable candidate for various medical applications.

Magnetic hyperthermia properties of iron oxide nanoparticles: The effect of concentration

We investigated the effect of concentration on magnetic hyperthermia properties of Fe3O4 nanoparticles (NPs). The NPs were synthesized by co-precipitation method at 80 °C. Scanning electron microscope image showed that the mean diameter of NPs is about 18 nm. The XRD pattern indicated that the sample is pure Fe3O4 with spinel structure and the FT-IR spectroscopy confirmed formation of metal-oxygen bonds in the octahedral and tetrahedral spinel sub-lattice which further confirmed crystalline structure of the sample. The hyperthermia property of Fe3O4 NPs was investigated via an induction heater generating alternating magnetic field with frequency of 92 kHz. The temperature rise (ΔT) of suspension in the AC magnetic field was studied on different concentrations of NPs and the specific absorption rate (SAR) was obtained from Box-Lucas equation and linear fitting of ΔT-time curve. The results showed that the ΔT sharply increases with increasing the NPs concentration while the SAR remains almost constant.

Preparation of Starch Nanoparticles in a New Ionic Liquid-in-Oil Microemulsion

In this work, a new room-temperature ionic liquid 1-hydroxypropyl-3-methylimidazolium acetate ([C3OHmim]Ac) was synthesized to dissolve starch and substitute for polar phase to form [C3OHmim]Ac/TX-100+1-butanol/cyclohexane microemulsions. The molecular structure of [C3OHmim]Ac was confirmed by means of 1H nuclear magnetic resonance (1HNMR) and electrospray ionization masss pectrometry (ESI–MS). Pseudo-ternary phase diagram, conductivity measurement and dynamic light scattering (DLS) were used to analyze the microregion of IL/O micro-emulsion. Starch nanoparticles were prepared in this novel IL/O micro-emulsion with octenyl succinic anhydride (OSA) maize starch as the raw material and epichlorohydrin as the cross-linker. Fourier transform infrared spectroscopy (FTIR) data demonstrated the formation of crosslinking bonds in starch molecules. The spectrum of XRD suggested that the crystal structure of starch was destroyed. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) both intuitively revealed that starch nanoparticles had good sphericity, small size and a relatively concentrated size distribution with the mean diameter of starch nanoparticles 105 nm.

Properties of Ce3+ -Doped Y3Al5O12 Phosphor Nanoparticles Formed by Laser Ablation in Liquid

Y3Al5O12: Ce3+ (YAG: Ce) nanoparticles were generated by the laser ablation from the micron-size YAG: Ce particles suspended in deionized water as a target suspension. The mean diameter of nanoparticles observed by a scanning electron microscopy were about 15–300 nm, and the morphology showed a dependence on an average energy density of Nd: YAG laser. The photoluminescence spectra exhibited peaks at 510 and 560 nm which are attributed to the 5d→4f transition of the Ce3+ activator. The luminescence intensity for the nanoparticles generated by the suspension increased with increasing the average energy density of Nd: YAG laser, and the intensity of 510 nm peak also exhibited higher than that for the nanoparticles generated by the micron-size particles precipitated on a bottom of vial. It was found that the laser ablation in liquid using the suspension was effective to generate the YAG: Ce phosphor nanoparticles.

Providing an Analytical Model in Determining Nanofluids

The influence of temperature, mean nanoparticle size and the nanoparticle concentration on the dynamic viscosities of nanofluids are investigated in an analytical method followed by introduction of modified equations for calculating the nanofluids’ viscosities. A new correlation is developed for effective viscosity based on the previous model where the Brownian movement of the nanoparticles is considered as the key mechanism. In previous studies, the proposed models were not appropriate for nanoparticles larger than 36 nm. They were also focused on low concentrations of nanoparticles up to 5%. The possibility of homogeneous dispersion of the nanoparticles and the Stokes law are observed here. This new model is explained in terms of temperature, mean nanoparticle diameter, nanoparticle volume concentration and both the nanoparticle and base fluid thermophysical characteristics for the effective viscosity of nanofluids. A combined correction factor is introduced to take into account the simplification for a free stream boundary condition outside the boundary layer. A good agreement is observed between the effective viscosity obtained in this new model and those of recorded experiments conducted for different nanofluids. The results show that the present model is valid for large volume concentration (0% < φ

An Inspection of Viscosity Models for Numerical Simulation of Natural Convection of Al2O3-Water Nanofluid with Variable Properties

Background: An innovative technique to improve the heat transfer involves dispersing the nanoscale particles in a base fluid, known as nanofluid. In earlier studies, to determine the nanofluid properties, especially the effective viscosity and thermal conductivity, basic models, namely the Brinkman model and Maxwell model have been employed. Yet these models do not take into account the dependency of the viscosity and thermal conductivity on the parameters, say, the mean diameter of the nanoparticles and the temperature. Considering this, recently, some researchers have studied nanofluid with variable properties and proposed new correlations, based on the experimental and theoretical data available in the literature, for calculating the nanofluid properties. The present paper aims to study the effects of uncertainties of different viscosity models of Al2O3–water nanofluid, namely the Brinkman, Abu-Nada, Khanafer and Vafai, and Corcione models on natural convection flow and heat transfer within a differentially heated square enclosure. Employing these models, effects of volume fraction and the mean diameter of nanoparticles, as well as the Rayleigh number, on the characteristics of flow and heat transfer are examined. Keywords: Natural convection, nanofluid, variable properties, viscosity models, numerical study, Nusselt number.

Interaction Effects in Assembly of Magnetic Nanoparticles

A specific absorption rate of a dilute assembly of various random clusters of iron oxide nanoparticles in alternating magnetic field has been calculated using Landau–Lifshitz stochastic equation. This approach simultaneously takes into account both the presence of thermal fluctuations of the nanoparticle magnetic moments and magneto-dipole interaction between the nanoparticles of the clusters. It is shown that for usual 3D clusters, the intensity of the magneto-dipole interaction is determined mainly by the cluster packing density η = NpV/Vcl, where Np is the average number of the particles in the cluster, V is the nanoparticle volume, and Vcl is the cluster volume. The area of the low frequency hysteresis loop and the assembly-specific absorption rate have been found to be considerably reduced when the packing density of the clusters increases in the range of 0.005 ≤ η < 0.4. The dependence of the specific absorption rate on the mean nanoparticle diameter is retained with an increase of η, but becomes less pronounced. For fractal clusters of nanoparticles, which arise in biological media, in addition to a considerable reduction of the absorption rate, the absorption maximum is shifted to smaller particle diameters. It is found also that the specific absorption rate of fractal clusters increases appreciably with an increase of the thickness of nonmagnetic shells at the nanoparticle surfaces.

Numerical Study on Conjugated Laminar Mixed Convection of Alumina/Water Nanofluid Flow, Heat Transfer, and Entropy Generation Within a Tube-on-Sheet Flat Plate Solar Collector

In this research, an inclined three-dimensional nanofluid-based tube-on-sheet flat plate solar collector (FPSC) working under laminar conjugated mixed convection heat transfer is numerically modeled. The working fluid is selected to be alumina/water (Al2O3/water) and results from heat transfer, entropy generation, and pressure drop points of view are being presented for various prominent parameters, namely volume fraction, nanoparticles diameter, Richardson and Reynolds numbers. According to the simulations, Nusselt number decreases as the Richardson number or volume fraction of the nanofluid rises, whereas heat transfer coefficient experiences an augmentation when volume concentration and the Richardson number surge. Also, data reveal that total entropy generation rate of the system declines when the alumina/water nanofluid is utilized inside the system as the volume fraction or the Richardson number increases. Additionally, it is found that increasing the nanoparticle volume concentration or the Richardson number diminishes the pressure drop considerably, whereas friction factor substantially proliferates as the Richardson number or volume fraction rises. Eventually, employment of larger alumina nanoparticles mean diameter eventuates in providing lower Nusselt number and apparent friction factor while it increases the pressure drop and heat transfer coefficient. Finally, comparing the efficiency of the presented FPSC design with those available in the literature shows a superior performance by the present design with its maximum occurring at 2 vol %.

A New Approach to Environmental Protection: Recovery of the Emulsifier OP-10

A magnetic emulsifier is synthesized by using the two-step method. Firstly, Fe3O4 nanoparticles are synthesized and then modified with silane coupling agent 3-(methacryloyloxy) propyltrimethoxysilane (KH-570). Secondly, the final composite particles are synthesized by the reaction between emulsifier octylphenol polyoxyethylene ethe OP-10 (C8H17C6H4O(CH2CH2O)10H) and modified Fe3O4 nanoparticles by silane coupling agent KH-570. After then the products are characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Raman spectroscopy, thermogravimetric analysis (TGA), and X-ray diraction (XRD). The result shows that the mean diameter of Fe3O4 nanoparticles is about 22.7 nm and the silane coupling agent KH-570 can be effectively modified Fe3O4 nanoparticles. In addition, this paper investigated the best hydrolysis conditions of coupling agent and the optimum reaction conditions of silane coupling agent on the Fe3O4 nanoparticles.

Fast and eco-friendly fabrication of uniform Ag substrates for highly sensitive surface-enhanced Raman scattering

This study proposed a fast, simple, eco-friendly method for obtaining highly sensitive and uniform surface-enhanced Raman scattering (SERS) of silver (Ag) nanotextured substrates decorated with silver nanoparticles in open air. By splitting conventional femtosecond pulses (subpulse delay Δt = 0 ps) into pulse trains (subpulse delay Δt = 3 ps), the mean diameter of Ag nanoparticles was reduced by almost half and the amount of Ag nanoparticles with a diameter ranging from 20 to 60 nm was increased by more than 11 times. The substrate fabricated by femtosecond pulse trains has four main merits as follows: (1) High sensitivity: the maximum SERS enhancement factor is 1.26 × 109; (2) High efficiency: the fabrication rate can be up to 1600 μm2/s, which is 20–40 times faster than femtosecond photochemical reduction; (3) Good reproducibility: the relative standard deviation of the Raman signal intensity is 10.7%, which is one-third of that for conventional femtosecond laser; (4) Eco-friendly fabrication: neither chemical reagents nor vacuum conditions are needed during the fabrication process.

Numerical Analysis of Compound heat transfer enhancement by single and two-phase models in parabolic through solar receiver.

A three dimensional numerical investigation of turbulent forced convection of Alumina/dowtherm-A nanofluid inside a non-uniformly heated parabolic trough solar collector receiver equipped by two longitudinal fins for improving heat transfer by single and two-phase modeling has been carried out. The heat flux around the absorber tube was obtained applying Monte Carlo ray trace technique. The numerical results were validating with the empirical correlations existing in literatures and good agreement was obtained. The calculated results demonstrate that two-phase models predict a higher convective heat transfer coefficient however the predictions of Darcy friction factor by single and two-phase approaches are essentially the same. Two-phase mixture model has been used to investigate the influence of nanoparticles mean diameter on heat transfer phenomena; it found that a smaller nanoparticles increase better convective heat transfer.DOI: http://dx.doi.org/10.5755/j01.mech.23.1.14053

Antimicrobial activity of Fe-loaded chitosan nanoparticles.

To increase the antimicrobial activities of chitosan, chitosan nanoparticles loaded with Fe2+ or Fe3+ were prepared by surfactant-assisted chitosan chelating Fe2+, Fe3+ and ionic gelation chitosan. Their chelating rates were determined by spectrophotometry. The particle sizes and zeta potentials of chitosan nanoparticles loaded with Fe2+ or Fe3+ were measured by size and zeta potential analysis. The nanoparticles antimicrobial activities were evaluated by different concentration against Escherichia coli, Staphylococcus aureus, Candida albicans in vitro. Results showed that the mean diameter of chitosan nanoparticles loaded with Fe2+ or Fe3+ were 206.4 and 195.2nm, respectively. Their zeta potentials were +28.82 and +28.26mV, respectively. The chelating rate of chitosan nanoparticles loaded with Fe2+ was greatly higher than with Fe3+. Their antimicrobial activity was showed greatly higher at lower concentrations compared to chitosan, and the antibacterial effect of chitosan nanoparticles loaded with Fe2+ or Fe3+ was preliminary observed.

Comparison of the Results of Measurements of the Sizes of Nanoparticles in Stable Colloidal Solutions by the Methods of Acoustic Spectroscopy, Dynamic Light Scattering, and Transmission Electron Microscopy

A comparative study is made of the use of transmission electron microscopy, dynamic light scattering, and acoustic spectroscopy for measuring the sizes of nanoparticles in stable colloidal solutions of Al2O3, TiO2, SiO2, and ZnO at different concentrations and mean nanoparticle diameters. For solutions containing dendritic agglomerates of nanoparticles along with individual nanoparticles, it is found that acoustic spectroscopy can be used to measure the sizes of individual nanoparticles and dynamic light scattering can be used to measure sizes of objects from a mass of nanoparticles and their agglomerates.

Curcumin-coordinated nanoparticles with improved stability for reactive oxygen species-responsive drug delivery in lung cancer therapy.

BackgroundThe natural compound curcumin (Cur) can regulate growth inhibition and apoptosis in various cancer cell lines, although its clinical applications are restricted by extreme water insolubility and instability. To overcome these hurdles, we fabricated a Cur-coordinated reactive oxygen species (ROS)-responsive nanoparticle using the interaction between boronic acid and Cur.Materials and methodsWe synthesized a highly biocompatible 4-(hydroxymethyl) phenylboronic acid (HPBA)-modified poly(ethylene glycol) (PEG)-grafted poly(acrylic acid) polymer (PPH) and fabricated a Cur-coordinated ROS-responsive nanoparticle (denoted by PPHC) based on the interaction between boronic acid and Cur. The mean diameter of the Cur-coordinated PPHC nanoparticle was 163.8 nm and its zeta potential was −0.31 mV. The Cur-coordinated PPHC nanoparticle improved Cur stability in physiological environment and could timely release Cur in response to hydrogen peroxide (H2O2). PPHC nanoparticles demonstrated potent antiproliferative effect in vitro in A549 cancer cells. Furthermore, the viability of cells treated with PPHC nanoparticles was significantly increased in the presence of N-acetyl-cysteine (NAC), which blocks Cur release through ROS inhibition. Simultaneously, the ROS level measured in A549 cells after incubation with PPHC nanoparticles exhibited an obvious downregulation, which further proved that ROS depression indeed influenced the therapeutic effect of Cur in PPHC nanoparticles. Moreover, pretreatment with phosphate-buffered saline (PBS) significantly impaired the cytotoxic effect of Cur in A549 cells in vitro while causing less damage to the activity of Cur in PPHC nanoparticle.ConclusionThe Cur-coordinated nanoparticles developed in this study improved Cur stability, which could further release Cur in a ROS-dependent manner in cancer cells.

Albumin nanoparticles for glutathione-responsive release of cisplatin: New opportunities for medulloblastoma

Redox-responsive nanoparticles were synthesized by desolvation of bovine serum albumin followed by disulfide-bond crosslinking with N, Nʹ-Bis (acryloyl) cystamine. Dynamic light scattering and transmission electron microscopy studies revealed spherical nanoparticles (mean diameter: 83nm, polydispersity index: 0.3) that were glutathione-responsive. Confocal microscopy revealed rapid, efficient internalization of the nanoparticles by Daoy medulloblastoma cells and healthy controls (HaCaT keratinocytes). Cisplatin-loaded nanoparticles with drug:carrier ratios of 5%, 10%, and 20% were tested in both cell lines. The formulation with the highest drug:carrier ratio reduced Daoy and HaCaT cell viability with IC50 values of 6.19 and 11.17μgmL−1, respectively. The differential cytotoxicity reflects the cancer cells’ higher glutathione content, which triggers more extensive disruption of the disulfide bond-mediated intra-particle cross-links, decreasing particle stability and increasing their cisplatin release. These findings support continuing efforts to improve the safety and efficacy of antineoplastic drug therapy for pediatric brain tumors using selective nanoparticle-based drug delivery systems.