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In this work, flower-like molybdenum disulfide (MoS 2 ) microspheres were produced with polyethylene glycol (PEG) to form MoS 2 -PEG. Likewise, gold nanoparticles (AuNPs) were added to form MoS 2 -PEG/Au to investigate its potential application as a theranostic nanomaterial. These nanomaterials were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), photoelectron X-ray spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), cyclic voltammetry and impedance spectroscopy. The produced hierarchical MoS 2 -PEG/Au microstructures showed an average diameter of 400 nm containing distributed gold nanoparticles, with great cellular viability on tumoral and non-tumoral cells. This aspect makes them with multifunctional characteristics with potential application for cancer diagnosis and therapy. Through the complete morphological and physicochemical characterization, it was possible to observe that both MoS 2 -PEG and MoS 2 -PEG/Au showed good chemical stability and demonstrated noninterference in the pattern of the cell nucleus, as well. Thus, our results suggest the possible application of these hybrid nanomaterials can be immensely explored for theranostic proposals in biomedicine.

In this work, the radioisotope 64 Cu was obtained from copper (II) chloride dihydrate in a nuclear research reactor by neutron capture, ( 63 Cu(n,γ) 64 Cu), and incorporated into boron nitride nanotubes (BNNTs) using a solvothermal process. The produced 64 Cu-BNNTs were analyzed by TEM, MEV, FTIR, XDR, XPS and gamma spectrometry, with which it was possible to observe the formation of 64 Cu nanoparticles, with sizes of up to 16 nm, distributed through nanotubes. The synthesized of 64 Cu nanostructures showed a pure photoemission peak of 511 keV, which is characteristic of gamma radiation. This type of emission is desirable for Photon Emission Tomography (PET scan) image acquisition, as well as its use in several cancer treatments. Thus, 64 Cu-BNNTs present an excellent alternative as theranostic nanomaterials that can be used in diagnosis and therapy by different techniques used in nuclear medicine.

The detailed study of graphene oxide (GO) synthesis by changing the graphite/oxidizing reagents mass ratios (mG/mROxi), provided GO nanosheets production with good yield, structural quality, and process savings. Three initial samples containing different amounts of graphite (3.0 g, 4.5 g, and 6.0 g) were produced using a bench reactor under strictly controlled conditions to guarantee the process reproducibility. The produced samples were analyzed by Raman spectroscopy, atomic force microscopy (AFM), x-ray diffraction (XDR), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR) and thermogravimetry (TGA) techniques. The results showed that the major GO product comprised of nanosheets containing between 1-5 layers, with lateral size up to 1.8 µm. Therefore, it was possible to produce different batches of graphene oxide with desirable physicochemical characteristics, keeping the amount of oxidizing reagent unchanged. The use of different proportions (mG/mROxi) is an important strategy that provides to produce GO nanostructures with high structural quality and scale-up, which can be well adapted in medium-sized bench reactor.

The South American palm weevil (SAPW), Rhynchophorus palmarum Linnaeus (Coleoptera: Curculionidae) is the main pest of Elaeis guineensis and damages palm trees with bud rot disease in the Americas. The effects of six neurotoxic insecticides (abamectin, carbaryl, deltamethrin, fipronil, imidacloprid and spinosad) were evaluated against SAPW for toxicity, survival, reproduction, and mortality. Abamectin (LC 50 = 0.33 mg mL -1 ), Carbaryl (LC 50 = 0.24 mg mL -1 ), deltamethrin (LC 50 = 0.17 mg mL -1 ), and fipronil (LC 50 = 0.42 mg mL -1 ) were the most toxic to SAPW. Adult survival was 95% without exposure to insecticides, decreasing to 78-65% in insects treated with the LC 25 and 49-35% in insects exposed to LC 50 . Sublethal doses of carbaryl, fipronil and imidacloprid showed significant effect on the reproduction of this insect. Mortality of SAPW populations caused by insecticides had similar effects in the laboratory and field conditions. The results suggest that carbaryl, deltamethrin, fipronil, and imidacloprid caused significantly higher mortality as compared to the control in SAPW and may be used to control its populations in oil palm trees where bud rot appears as the key disease for SAPW attraction and infestation.