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Purpose: Cancer is an example of the most important growing diseases in human society and scientists are trying to treat it without considerable side effects on patient's health. Solid lipids are colloidal nanoparticles that were used in drug delivery due to their several advantages. Methods: In this work, surface modified targeted solid lipid nanoparticles (SLNs) were fabricated by nano-homogenizer using tripalmitin glyceride and stearic acid as lipid constituents. The size of nanoparticles and morphological evaluations were surveyed using particle size analyzer, scanning electron microscopy; Fourier transforms infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). Results: The particle size of 148.5 and appropriate polydispersity index were achieved for lipid nanoparticles with an entrapment efficiency of 86.1%. The FT-IR analysis confirmed the coupling of lysine to the free functional group of SLNs. DSC proved the conjugation of amino acid to the surface of carriers. The in vitro epirubicin (EPI) release test exhibited the further controlled release phenomenon for the lysine conjugated nanoparticles. The cytotoxicity assay showed lower IC50 of lysine conjugated SLNs of EPI on the investigated cell line. Conclusion: These studies showed that the fabricated targeted carrier has a very remarkable anticancer effect on breast cancer cell lines in comparison with pure drug. [ABSTRACT FROM AUTHOR]

Treatment methods for breast cancer are not specific and each one has its own drawbacks. For this reason, scientists are seeking ways in which specifically affect cancer cells. Photothermal therapy is a method that uses near-infrared (NIR) laser energy to create sufficient heat to destroy cancer cells. In this study, the photothermal effect of gold nanorods (GNRs) was investigated for breast cancer treatment in vitro and in vivo. GNRs with the peak absorption of 808 nm were synthesized and conjugated with Herceptin (antiHER2). After confirming the characteristics of the prepared conjugate, the therapeutic effect of the new agent was studied on SK-BR-3 cell line and BALB/c mouse model bearing breast tumor using the NIR laser. The cytotoxicity assay showed the biocompatibility of PEGylated GNRs-HER conjugate. Through the in vitro photothermal study, significant cell death was observed in breast cancer cells incubated with the conjugate along with the laser irradiation. Afterward, the biodistribution of the conjugate in the mouse model with breast tumor showed the considerable localization of new agent in breast tumor in comparison with other organs 24 h postinjection. The animal study showed a significant decrease in tumor growth rate as well as the increased lifespan of treated mice with breast tumor in comparison with the control groups. [ABSTRACT FROM AUTHOR]

The aim of this study was preparation and optimisation of a controlled‐release delivery system to decrease the dose‐dependent side effects of gentamicin. Hydrogel nanoparticles composed of a polycationic polymer (chitosan) and an inorganic polyanion (sodium tripolyphosphate) were fabricated in the presence of gentamicin. An experimental design was drawn upon to determine the optimum condition of nanoparticle preparation. Various features of the nanoparticles including drug loading parameters, particle size distribution, zeta potential and in vitro drug release profile were evaluated. Ultimately, the antimicrobial activity of the gentamicin‐loaded nanoparticles was analysed by determination of the minimum inhibitory concentration (MIC) and the potency test. As a result, the nanocarriers with an average size of about 250 nm (unloaded) and 493 nm (gentamicin‐loaded) were obtained with unimodal distribution and a notable polydispersity index (≤0.3). The drug loading efficiency was between 28 and 32%. The gradual and sustained releases (∼90%) of gentamicin were achieved in 24 h. The MIC and potency test showed no significant decrease in the antibacterial activity of gentamicin‐loaded nanoparticles. The outcomes demonstrated that the optimised chitosan nanogels prepared in this study can be considered as a suitable carrier for a controlled release system. [ABSTRACT FROM AUTHOR]

Due to the strong effect of nanoparticles' size and surface properties on cellular uptake and bio‐distribution, the selection of coating material for magnetic core–shell nanoparticles (CSNPs) is very important. In this study, the effects of four different biocompatible coating materials on the physical properties of Fe3 O4 (magnetite) nanoparticles (NPs) for different biomedical applications are investigated and compared. In this regard, magnetite NPs are prepared by a simple co‐precipitation method. Then, CSNPs including Fe3 O4 as a core and carbon, dextran, ZnO (zincite) and SiO2 (silica) as different shells are synthesised using simple one‐ or two‐step methods. A comprehensive study is carried out on the prepared samples using X‐ray diffraction, vibrating sample magnetometry, transmission electron microscopy and Fourier transform infrared spectroscopy analyses. According to the authors' findings, it is suggested that carbon‐ and dextran‐coated magnetite NPs with high Ms have great potential in the application of magnetic resonance imaging contrast agents. Moreover, silica‐coated magnetite NPs with high coercivity are potentially suitable candidates for hyperthermia and ZnO‐coated Fe3 O4 is potentially suitable for photothermal therapy. [ABSTRACT FROM AUTHOR]