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The development of effective drug delivery systems is crucial for improving cancer treatment outcomes. A promising carrier using a combination of DNA and exosomes (EXO) was synthesized to sustain the release of the powerful anticancer drug 5‐fluorouracil (5‐FU). The carrier was prepared by encapsulating 5‐FU‐loaded exosomes (5‐FU.EXO) in the heated DNA carriers (5‐FU.EXO@DNA). Alteration of the DNA structure was studied using molecular dynamics. The physicochemical properties of the carriers were characterized using fourier‐transform infrared spectroscopy (FTIR), field‐emission scanning electron microscopy (FESEM), and dynamic light scattering (DLS). The 5‐FU.EXO@DNA carrier exhibited good stability and biocompatibility, with a uniform size distribution (709±269 nm) and a zeta potential of +312 mV. The interaction between 5‐FU and DNA was confirmed using molecular docking. In vitro release studies showed that both 5‐FU@DNA and 5‐FU.EXO@DNA carriers achieved sustained release of 5‐FU for 576 h, with cumulative releases of approximately 83 % and 89 %, respectively. The 5‐FU release profile showed 40 % release over 86 h. The release rate and other kinetic parameters were also determined. Furthermore, the release kinetics followed by the Korsmeyer‐Peppas model and the diffusion mechanism plays a significant role in controlling the release process. [ABSTRACT FROM AUTHOR]

High entropy alloys, especially AlCoCrFeNi, have received much attention in recent years due to their unique properties. Therefore, the study of the various properties of this alloy has been the subject of recent fundamental research. In this study, the electrochemical behavior of zirconia-reinforced AlCoCrFeNi high entropy alloy has been investigated. For this purpose, the OCP and Tafel tests on the samples of AlCoCrFeNi-x wt% ZrO2 (x = 0, 5, 10) were performed in a 3.5 wt% NaCl solution. The SEM images were obtained from the corrosion products. Subsequently, the samples were soaked in the above solution for 24, 48, and 72 h, followed by an impedance test. The results of the Tafel test and the SEM images show that the addition of zirconia up to 5 wt% and 10 wt% to the mentioned alloy decreases and increases the corrosion resistance, respectively. The increase in the FCC phase in AlCoCrFeNi-5 wt% ZrO2 decreased the corrosion resistance. The improvement in corrosion resistance in AlCoCrFeNi-10 wt% ZrO2 zirconia is due to the increase in the ceramic phase and the consistency between the passive layers. The EIS test showed that the addition of zirconia to the AlCoCrFeNi system delays the formation of passive layers by up to 72 h, as it leads to the formation of a rough surface. [ABSTRACT FROM AUTHOR]

Li2FeSiO4 (LFS) has received remarkable attention due to its high thermal stability, environmental benignity, low cost, and low toxicity. However, the electrochemical performance of the material is restricted by achieving its high theoretical capacity (∼330 mA h g−1). Doping is a potentially effective method to enhance the electrical conductivity and performance, and to reduce the operation voltage of the LFS cathode material. In this study, using density functional theory (DFT), fluorine-doped LFS (Li2FeSiO3.5F0.5) and chlorine-doped LFS (Li2FeSiO3.5Cl0.5) are evaluated. The structural properties, structural stability after extraction of the lithium-ions, cycle ability, chemical stability, cell voltage, electrical conductivity, and rate capability are assessed for the considered cathode materials. These theoretical studies predict that F and Cl doping enhances structural stability, chemical stability, electrical conductivity, rate capability, and reducing cell voltages to put the material in the electrolyte voltage tolerance to extract two Li per formula. Accordingly, the results show that the doping increases the performance, rate capability, stability, and capacity of LFS. [ABSTRACT FROM AUTHOR]

In the present study, hybrid nanostructures of porous Co3O4 nanoball/carbon aerogel were prepared via the in situ growth of Co3O4 nanoballs with nanosized uniform structures within the pores of a pre-synthesized atmospheric pressure-dried highly mesoporous carbon aerogel. The three-dimensional structure of the carbon aerogel with appropriate electrical conductivity, high specific surface area and mesopore volume enabled the fabrication of an electrode with appropriate electrochemical performance when combined with the porous Co3O4 nanoball. This Co3O4 nanoball/carbon aerogel hybrid nanostructure exhibits a large specific capacitance of 350 F g−1 at the current density of 1 A g−1 in 6 M KOH electrolyte in a three electrode system. Furthermore, due to its special nanostructure, this electrode exhibits an energy density of 23.82 W h kg−1 at power density of 95.96 W kg−1 in 6 M KOH and an energy density of 19.44 W h kg−1 at power density of 76.2 W kg−1 in 2 M KOH. Cycling in the potential range of 0.0 to 1 V at a current density of 1 A g−1 in a symmetrical configuration (two-electrode system) exhibits an ascending capacitance trend with 210% of capacity retention after 6000 cycles. These prominent performance characteristics demonstrate the promising role of the prepared hybrid nanostructure for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Ab-initio quantum mechanical calculation is used to calculate the 14N and 2H nuclear quadrupole resonance (NQR) parameters (η and χ) of CH3N2+ ion and the ion shellvated by H2 molecules [CH3N2+(H2)n=1–9]. On the basis of NQR parameters, three distinct shells (A, B and C) were identified. To obtain these data we had to evaluate the electric field gradient (EFG) around any atom in each situation. EFG’s were calculated by the Gaussian 98 program using the MP2/6-311G** method. [Copyright &y& Elsevier]

In this Letter NQR frequencies of 35Cl in some organo-germanium chlorides are calculated by an ab initio method. The Ge–O distances in structures (1)–(3) (Fig. 1Fig. 1Structure of: (1) ; (2) ; (3) .) were varied in the range 1.5–3 A˚. After the optimization of the geometry of molecule in each selected distance, the 35Cl frequencies were calculated (νQcal). Employing the correct value of νQcal leads us to reliable Ge–O distances. All calculations have been carried out with the Gaussian 98 program. The differences between νQexp and νQcal in these structures were chosen as a measure to select the proper Ge–O distance. Our results are in agreement with (XRD) data. [Copyright &y& Elsevier]