Cationic dye Acridine orange (AO) has wide applications especially in biologicalfields such as analysis of lysosomal and mitochondria content by flow cytometryand so on. In the current work, spectroscopy of acridine orange (AO) dye at bothlow concentrations (mdye/mwater=6.25×10-5, 3.12×10-5) and high concentrations(mdye/mwater=0.002, 0.001) was studied in confined water nanodroplets withinwater/AOT/n-hexane microemulsions (MEs) at a constant water content (W=[Water]/[AOT]=10) and as a function of mass fraction of droplet (MFD) usingabsorption and fluorescence spectroscopic techniques. The absorption spectraof the dye at high concentrations of Acridine orange (AO) dye molecules showedthat the absorption spectra of the samples deviated from Beer’s law, and arebroadened at larger MFD due to the interactions of AO dye molecules. Thefluorescence spectrum investigated at two higher concentrations (0.002, 0.001)and low concentrations (6.25×10-5, 3.12×10-5). At high concentration of the dye,quenching of fluorescence intensity observed due to the accumulation of the dyemolecules, coupled with a red shift with increasing MFD. However, in the lowerconcentration regime, enhancement of fluorescence intensity was observed withincreasing MFD. The Stokes’ shift of the dye for both high and low concentrationsincreased with MFD, but largely at high concentrations compared to that at lowconcentrations. پرونده مقاله

Biologically, two parameters of size and surface charge of the nanoparticles, especially therapeutic nanoparticles influence their kinetics in vivo as well as their interaction with the cellular and biological membranes and resulting their efficacy. So effective characterization of nanomaterials including nanometer-sized particles and micelles is a key issue to develop the well-deserved and well-defined Nano-formulations focus on the therapeutic goals in nanomedicine research. Determining the particle size and surface charge of nanoparticles are essential to characterize therapeutic nanoparticles properly. Measurements related to techniques of dynamic light scattering (DLS) and zeta potential (ZP) are known as easy, simple, and reproducible tools to obtain the size and surface charge of nanoparticles. Regarding characterization of particle size and surface charge by the DLS and ZP there is challenges for researchers to interpret and analyze the exported data effectively due to lack of adequate understanding focus on physical principles governing on the operating system of these techniques and how preparing samples for characterization and so on. With this in mind, this review tries to address this issue focus on the fundamental principles governing on techniques of DLS and ZP to better analyzing and interpreting the reported results such as hydrodynamic size, diffusion, inter particular interactions as well as study of the colloidal system stability based on surface charge of nanoparticles. پرونده مقاله

Metal oxide nanoparticles due to their antioxidant properties have attractedsignificant attention and exhibited good potential for use in cancer theranostics.Owing to the poor absorption in the physiological environment, they are anideal candidate to act as nanocarriers in targeted drug delivery and bioimaging.This feature can be successfully implemented in live monitoring and imagingapplications, which offer the possibilities and scope for optical, magneticresonance, and nuclear imaging. The environment of malignant cells likethe rapid proliferation of cells, specific antigen expressions, and leaky tumorvasculature can be used by the modifications in their morphology and surfacefunctionalization. Ceria (CeO2) nanoparticles have been fascinating in this regard.Different properties such as size, agglomeration behavior, and surface chargedensity facilitate the interaction of nanoparticles with cancer cells. Compared toother nanoparticles, CeO2 nanoparticles have a potential for pharmaceutical usesince they can act as a therapeutic agent in different disorders such as cancer,inflammation, and neurodegeneration, due to the ability to exhibit variableoxidation state at the nanoparticle surface. Recent literature reports the ecofriendlyor ‘green’ synthesis of CeO2 nanoparticles in which the biological agentacts as stabilizers for a cost-effective and feasible mode of preparation. In thisreview, we focus on recent literature on CeO2 nanoparticles with an emphasis onthe methods of fabrication and biomedical applications. پرونده مقاله

Deleterious effect of high concentration fluoride in water resources on the healthof human. The MgO supported Fe-Co-Mn nanoparticles were produced via coprecipitationmethod and characterized by SEM and FTIR techniques. In the work,the adsorption process optimization was performed by response surface modelingwith the help of Minitab 16 software. The effect of independent parameters suchas pH ( 3-11), the initial dose (0.02-0.1 g/L), the initial concentration of the fluoride(10-50 mg/L) and reaction time (30-180 min) were optimized to obtain the bestresponse of fluoride removal using the statistical Box-Behnken in responsesurface modeling procedure. Conditions for the pH(5), the initial concentrationof nanoparticle (0.05 g/L), the initial concentration of fluoride (50 mg/L) and theprocess time(90 min) were obtained as Min respectively. Under these conditions,the removal efficiency of the fluoride by MgO capped Fe-Co-Mn nanoparticlesequal to 84.64% were achieved. ANONA high correlation coefficients for theproposed model was also obtained (adjusted –R2=0.9993 and R2=0.9984). Theequilibrium data were analyzed using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The Langmuir model was found to be describingthe data. Kinetic studies showed that the adsorption followed a pseudo-secondorder reaction. پرونده مقاله