Silver nanoparticles have a wide range of research, industrial and biomedical applications that make it essential to develop a low cost and eco-friendly approach with scaling up potential. Green synthesis of nanoparticles through bio-reactions leads to a reduction of silver ions to particles could be an acceptable selection using no additional reducing chemicals. Moreover, the simplicity of scale-up processes of the method makes it more efficient than chemical and physical synthesis methods. In this study, Datura stramonium leaf extract and sodium citrate were used as biological and chemical reducing and stabilizing agents to make silver nanoparticles. The main goal is to comprise properties and evaluate antibacterial activity of nanoparticles synthesized through two approaches. Size and morphology compared between the two types of the synthesized nanoparticle by UV-Visible spectroscopy, DLS, AFM, TEM and their antibacterial effects were evaluated through growth inhibition MIC and MBC methods. The results showed narrow size range, spherical shape, high anti-oxidant, antibacterial and DNA cleavage activities of green synthesized silver nanoparticles comparing to less average size, wider range of nanoparticle size, no anti-oxidant activity and less antibacterial and DNA cleavage activities of chemically synthesized nanoparticles. The green synthesized silver nanoparticles had more desirable characteristics and biological activities compared to chemically synthesized nanoparticles. For instance, the green nanoparticles showed narrow size range, spherical shape, high anti-oxidant, antibacterial and DNA cleavage activities versus the chemically synthesized which had less average size, higher range of nanoparticles size, no anti-oxidant activity and less antibacterial and DNA cleavage activities.

Described here is a simplified method for fabrication of DNA nanotubes using a minimum numbers of staple oligomers for DNA origami. For this purpose, the cylindrical nanotemplates with two sticky ends have been designed using caDNAno software. Then, the nanostructures were shaped in an optimized experimental condition via an origami-based self-assembly reaction. Finally, the produced nanostructures were joined together through their sticky ends using a ligase enzyme. Transmission electron microscope confirmed fabrication of these elongated nanotubes. In addition, high-resolution microscopy of DNA nanotubes by scanning tunnelling microscope indicated efficient attachments of the primarily DNA nanostructures via their sticky ends. The results demonstrated that a ligase treatment of cylindrical DNA nanostructures with the sticky ends made DNA nanotubes with standard shapes using minimum numbers of staples.

One of the main challenges in wound healing is the wound infection due to various causes, of which moisture is the most important reason. Owing to this fact, wound dressings that can collect wound moisture in addition to showing antibacterial properties have provided an important basis for wound healing research. In this study, gelatin and poly lactic acid (PLA) polymers were used in a wound dressing textile to provide gelation and structure strength properties, respectively. Meanwhile, silver nanoparticles (SNPs) synthesized through the green method were integrated into these fibers to provide the formed textile with antibacterial properties. Nanoparticles were made using donkey dung extract, and nanofibers were produced by the solution blow spinning method which has high production efficiency and low energy consumption among spinning methods. The produced nanoparticles were characterized and evaluated by UV-Vis, DLS, XRD, and FTIR methods, and the production of silver nanoparticles that were coated with metabolites in the extract was proven. In addition, the morphology and diameter of the resulted fibers and presence of nanoparticles were confirmed by the SEM method. The size and size distribution of the synthesized fibers were determined through analyzing SEM results. Gelatin nanofibers demonstrated a mean size of 743 nm before and 773 nm after nanoparticle coating. PLA nanofibers demonstrated a mean size of 57 nm before and 182 nm after nanoparticle coating. Finally, 335 nm was the mean diameter size of gelatin/PLA/SNPs nanofibers. Also, the textiles synthesized by PLA and gelatin which contained silver nanoparticles showed higher antibacterial activity against both gram-positive and gram-negative species compared to PLA and gelatin tissues without nanoparticles. Cytotoxicity test on L929 cells showed that silver nanoparticles incorporated textiles of PLA and gelatin show a very low level and non-significant toxicity compared to the free particles.

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Recently, therapeutic applications of modified magnetic nanoparticles have attracted the attention of many researchers. The reason is the ability to develop nano drugs as cancer treatment agents. For this purpose, these particles must have a tiny size, intrinsic magnetic properties, imaging effectiveness, the ability to target the drug, and high drug absorption. Although studies have been performed on the anti-cancer properties of curcumin/nanoparticles, no comprehensive research has been performed to evaluate its anti-cancer and the normal cell toxicity of this drug system for breast cancer treatment. This study designed a curcumin-loaded MNPs (MNPs@CUR) formulation to accomplish these unique features. Using the diffusion process, chemical precipitation was used to make MNPs, which were then loaded with curcumin (CUR). Transmission electron microscopy (TEM) was used to study the morphology and size of MNP-CUR. The fabricated MNPs had spherical shapes with an average length of 23.22 nm. The presence of curcumin on the surface of MNPs was approved using Fourier transform infrared (FTIR) analysis. The X-ray diffraction (XRD) diffractogram confirmed the face cubic center (fcc) character of MNPs.  After 24 hours of incubation with 4t1 breast cancer cells, MNPs@CUR anticancer effects were evaluated. MNPs@CUR displayed a concentration-dependent preference for applying anticancer effects on 4t1cells (IC50=108 µg/ml).  Separated in vivo anti-tumor studies of coated/naked nanoparticles and curcumin also demonstrated that MNPs@CUR eliminated tumor mass. The cytotoxicity and genotoxicity against normal peripheral blood mononuclear cells (PBMC) were also measured by 2,5-diphenyl-2H-tetrazolium bromide (MTT) electrophoresis DNA digestion methods respectively for MNPs@CUR and naked MNPs. Cytotoxicity was demonstrated at high concentrations of MNP@CUR (991 µg/ml), while naked nanoparticles showed approximately no toxicity and neither had genotoxicity.

Green synthesis methods are environmentally friendly, cost effective and nonhazardous for biomedical applications in comparison with other methods. The aim of the study was green synthesis of silver nanoparticles using medicinal animal dung extract as a reducing, capping and stabilizing agent for the first time among other synthesis methods of silver nanoparticles. Female donkey’s dung was capable to reduce silver ions to nanoparticles and stabilize them. Silver nanoparticles with average sizes of 36 nm were synthesized and characterized by UV-Vis, FT-IR, XRD and TEM. Moreover, synthesized nanoparticles were analyzed in terms of anticancer activity by MTT assay on MCF-7 cell line. UV–Visible spectrophotometer showed an absorbance peak in the range of 414-433 nm. To identify the phytochemical coating of particles, FTIR analysis was used. Transmission electron microscope (TEM) images and X-ray diffraction (XRD) confirmed the formation of small spherical silver nanoparticles. The MTT assay revealed potent anticancer effects of the aqueous extract synthesized nanoparticles on MCF-7 cells, incubated for 24 hours. Based on the current findings, it is strongly believing that the use of donkey’s dung offers large scale production of biocompatible silver nanoparticles that can be suggested to possess valuable anticancer agents against breast cancer cell lines.

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