Preparation and application of various nanoparticles in biology and medicine

The present paper considers prospects for application of various nanoparticles in biology and medicine. Here are presented data on preparation of gold and silver nanoparticles, and effects of shape of these nanoparticles on their optical properties. Application of these nanoparticles in diagnostics, for drug delivery and therapy, and preparation of magnetic nanoparticles from iron and cobalt salts are also discussed. Application of these nanoparticles as magnetic resonance imaging (MRI) contrast agents and as vehicles for drug delivery, and preparation of quantum dots and their application as prospective nanoparticles for multiplex analysis and for visualization of cellular processes will be tackled. Finally, prospects for new types of nanocomposites (metallic nano-shells) will be not overlooked.

Effect of nanoparticles suspension on the growth of mung (Vigna radiata) seedlings by foliar spray method

<p>The present experimental investigation demonstrates the effect of nano-ZnO, nano-FeO and nano-ZnCuFe-oxide particles on the growth of mung (<em>Vigna radiata</em>) seedling. The study was carried out by spraying optimum concentrations of nanoparticles in suspension form on hydroponically grown test units and examining the effect on the shoot growth of seedlings. Based on biomass assay, it was found that the seedlings displayed good growth over control, demonstrating a positive effect of the nanoparticle treatment. The best performance was observed for nano-ZnCuFe-Oxide followed by nano-FeO and nano-ZnO. Absorption of nanoparticles by plant leaves was also detected by inductive coupled plasma/atomic emission spectroscopy.</p>

Preparation, characterization and scale-up of sesamol loaded solid lipid nanoparticles

Sesamol loaded solid lipid nanoparticles (SSLNs) were prepared with the aim of minimizing its distribution to tissues and achieving its targeting to the brain. Three scale-up batches (100x1 L) of S-SLNs were prepared using a microemulsification technique and all parameters were statistically compared with the small batch (1x;10 mL). S-SLNs with a particle size of less than 106 nm with a spherical shape (transmission electron microscopy) were successfully prepared with a total drug content and entrapment efficiency of 94.26±2.71% and 72.57±5.20%, respectively. Differential scanning calorimetry and infrared spectroscopy confirmed the formation of lipidic nanoparticles while powder X-ray diffraction revealed their amorphous profile. S-SLNs were found to be stable for three months at 5±3°C in accordance with International Conference on Harmonisation guidelines. The SLN preparation process was successfully scaled-up to a 100x batch on a laboratory scale. The procedure was easy to perform and allowed reproducible SLN dispersions to be obtained.

Biological synthesis of cobalt ferrite nanoparticles

A low-cost green and reproducible yeast (<em>Saccharomyces cerevisiae</em>) mediated biosynthesis of cobalt ferrite nanoparticles is reported. The synthesis is performed at close to room temperature in the laboratory. X-ray, Fourier transform infrared spectroscopy and high resolution transmission electron microscopy analyses are performed to ascertain the formation of cobalt ferrite nanoparticles. Individual nanoparticles, as well as a very few aggregate having the size of 3-15 nm, were found. The vibrating sample magnetometer measurement showed superparamagnetic behavior in cobalt ferrite nanoparticles. The mechanism involved in the biosynthesis of cobalt ferrite nanoparticles has also been discussed.

Synthesis of nanomaterials using expired medicines: an eco-friendly option

Expired medicines are a burden to the environment. In this paper, a novel method is suggested to reutilize expired medicines in order to assess the possibilities of synthesizing a variety of nanomaterials. To this end, expired flouroquinolone (norfloxacin) and tinidazole combinations were used to synthesize metal (Au), oxide (ZrO₂) and chalcognide (CdS) nanoparticles using for the first time a green chemistry approach. Au, ZrO₂ and CdS nanoparticles are available in convenient sizes of 6 nm, 26 nm and 18 nm, respectively, and remain stable for at least six months. This novel procedure is possible thanks to their molecular organization and elements. The inclusion of a fluorine atom in a drug molecule may influence both the disposition of the drug and its interaction with its pharmacological target; for example, the effects of fluorine substitution on the inter- and intra-molecular forces that affect binding of ligands. The presence of sulfur in the tinidazole molecules may also have contributed towards synthesis through proton withdrawal. The nanomaterials synthesized in this way were characterized using X-ray diffraction analysis and transmission electron microscopy to identify the formation of the desired nanoparticles. This single-step green approach is very convenient, simple and can be extended to synthesize a variety of nanomaterials that might find new technological and pharmaceutical applications.

Iron oxide nanoparticles coated with β-cyclodextrin polluted of Zea mays plantlets

The present experimental investigation is focused on the study of assimilatory pigments and nucleic acid levels in young plants intended for agricultural use (<em>Zea mays</em>) in presence of water based magnetic fluid added in culture medium. The magnetic fluid was constituted by coating the nanosized magnetic nanoparticles (with 10.55 nm average value of the physical diameter) with β-cyclodextrin (C42H70O35) and further dispersion in water. After germination, various volume fractions (between 10 mL/L and 500 mL/L) of the magnetic fluid was added daily in the culture medium of <em>Zea mays</em> plants still at their early ontogenetic stages. Toxicity symptoms leaded to brown spots covering the leaf surface for the highest magnetic fluid volume fractions used, a putative oxidative stress generated by iron excess treatment. Relatively small volume fraction of magnetic fluid solutions induced the increase of <em>chlorophyll a</em> level (up to 38%), the main photosynthesis pigment, as well that the nucleic acid level (up to 57%) in <em>Zea mays</em> plantlets. All volume fractions of magnetic fluid solutions analyzed may have severe disruptive effects such as the ratio <em>chlorophyll a/chlorophyll b</em> (about 50% decreasing).

Nanotechnology developments: opportunities for animal health and production

Nanotechnology has opened up new vistas for applications in molecular biology, biotechnology and almost all the disciplines of veterinary and animal sciences. Excellence in animal health and production can be achieved by translation of this newer technology to create effective services and products for animals. The ability to manufacture and manipulate matter on the nanoscale has offered opportunities for application in diverse areas of animal sciences. Nanosensors, nanovaccines, adjuvants, gene delivery and smart drug delivery methods have the potential to revolutionize animal health and production. There can be numerous applications of the nanomaterials for disease diagnosis, treatment, drug delivery, animal nutrition, animal breeding, reproduction, tissue engineering and value addition to animal products. This paper reviews the recent developments in nanotechnology research and opportunities for application in animal sciences.

Green synthesis of Silver nanoparticles through Calotropis gigantea leaf extracts and evaluation of antibacterial activity against Vibrio alginolyticus

Green synthesized silver nanoparticles by <em>Calotropis gigantea</em> leaf extract were used to study the inhibitory activity against pathogenic <em>Vibrio alginolyticus</em>, isolated from wild <em>Artemia franciscana</em> cysts. Silver nanoparticle synthesis was observed using UV-visible spectroscopy and the morphological characteristics were analyzed by atomic force microscope (AFM). In the present study, increasing concentrations of silver nanoparticles synthesized on LB agar plates effectively reduced the number of colonies of <em>V. alginolyticus</em>. A decrease in colonies (CFUs) was observed at 5 mg/mL of silver nanoparticle concentration and the complete inhibition of V. alginolyticus was observed at 20 mg/mL of silver nanoparticle concentration on LB agar plates. In vivo controlling efficiency of silver nanoparticles was tested in an <em>A. franciscana</em> hatching system. Effective control of <em>V. alginolyticus</em> in brine shrimp <em>A. franciscana</em> hatching units was achieved by experimental infection and treatment with silver nanoparticles. Experimental infection studies showed that <em>V. alginolyticus</em> infected <em>Artemia</em> nauplii treated with silver nanoparticles (10 mg/mL) had greater survival (&gt;40%) than silver nanoparticles not treated with nauplii. Based on the findings of this study, it is recommended that low concentrations of green synthesized silver nanoparticles should be further investigated for other potential experimental models to control potential medical pathogens.

Quantum dots nanoparticle-based lateral flow assay for rapid detection of Mycobacterium species using anti-FprA antibodies

A lateral flow (LF) device combined with quantum dots (QDs) technology was developed for rapid detection of a specific mycobacterial flavoprotein reductase (<em>fprA</em>). In order to develop the LF assay based on a double-antibody sandwich format, two monoclonal antibodies recognizing different epitopes located in separated <em>fprA</em> domains were identified. The first monoclonal antibody was immobilized onto the detection zone of a porous nitrocellulose membrane, whereas another monoclonal antibody was conjugated to QDs nanoparticles as a detection system. Using these monoclonal antibodies we recorded a good fluorescence signal, the intensity of which was directly proportional to the concentration of <em>fprA</em> protein. The use of antibodies conjugated with fluorescent semiconductor QDs via biotin-streptavidin bridge, allowed the detection of <em>fprA</em> protein at concentrations as low as 12.5 pg/μL in less than 10 min. The reported technology could be useful in the diagnostic investigation of <em>Mycobacterium tuberculosis</em> and other human pathogens in clinical specimens.

Fast and complete degradation of Congo red under visible light with Er3+ and Nd3+ ions doped TiO2 nanocomposites

We report fast and complete destruction of the dye Congo red (CR) under visible light in the presence of Nd3+ and Er3+ doped TiO2 nanocomposites (NCs). TiO2 NCs with general composition TiO2[R2O3]x, {x=0.1, 0.2; R≡ Nd, Er} and particle size 12-16 nm were synthesized through co-precipitation/hydrolysis (CPH). A set of similar composites was also prepared through solid state reaction (SSR) route, which produced 31- 47 nm particles. After characterization, visible light photocatalytic activity of all the samples was recorded for the degradation of CR. NCs with molar concentration x=0.2 of both doping types produced close to 100% degradation in 180 min. The apparent rate constant (kobs) was found to be 2.91×10–2 min–1 and 2.36×10–2 min–1, for these Nd3+ and Er3+ doped NCs, respectively. The other NCs with x=0.1, also showed significant degradation of CR, but the samples prepared through SSR performed worse. The excellent degradation obtained with the NCs may be attributed to their small particle size. Moreover, the doping of Nd3+ and Er3+ ions further supported the photocatalysis through formation of intermediate energy levels within the band gap of TiO2. These new levels not only acted as electron traps for efficient suppression of the undesired e–/h+ recombination, but also facilitated to a certain extent the absorption of visible irradiation.