Starch Nanocomposite Films: Migration Studies of Nanoparticles to Food Simulants and Bio-Disintegration in Soil.

In this work, films containing AgNPs were obtained by different green synthesis techniques (AgNP in situ and AgNP L). The inclusion of nanoparticles in the starch matrix improved both mechanical and barrier properties. The migration of AgNPs from the nanocomposite material to three food simulants (water, 3% / acetic acid and 15% / ethanol) was studied.

Nanocomposite starch-based films containing silver nanoparticles synthesized with lemon juice as reducing and stabilizing agent.

Silver nanoparticles (AgNP L) synthesis using the active compounds of lemon juice was optimized. The obtained nanoparticles were included in starch-based film formulations, studying the relevant properties that condition their application in the packaging area. The optimized conditions for AgNP L' synthesis were 30 min at 90 °C, which led to the lowest nanoparticle size (5.

Drug repurposing for the treatment of alveolar echinococcosis: and effects of silica nanoparticles modified with dichlorophen.

Alveolar echinococcosis is a neglected parasitic zoonosis caused by the metacestode Echinococcus multilocularis, which grows as a malignant tumour-like infection in the liver of humans. Albendazole (ABZ) is the antiparasitic drug of choice for the treatment of the disease. However, its effectiveness is low, due to its poor absorption from the gastro-intestinal tract.

EXAFS and DFT study of the cadmium and lead adsorption on modified silica nanoparticles.

Silica nanoparticles of 7 nm diameter were modified with (3-aminopropyl) triethoxysilane (APTES) and characterized by CP-MAS (13)C and (29)Si NMR, FTIR, zeta potential measurements, and thermogravimetry. The particles were shown to sorb successfully divalent lead and cadmium ions from aqueous solution. Lead complexation with these silica nanoparticles was clearly confirmed by EXAFS (Extended X-ray Absorption Fine Structure) with synchrotron light measurements.

Photodegradation routes of the herbicide bromoxynil in solution and sorbed on silica nanoparticles.

Some organic contaminants dissolved in natural waters tend to adsorb on suspended particles and sediments. In order to mimic the photodegradation routes in natural waters of bromoxynil (BXN) adsorbed on silica, we here prepare and characterize silica nanoparticles modified with BXN (NP-BXN). We measure the direct photolysis quantum yield of aqueous BXN at 307 nm (0.

The effect of dichlorophen binding to silica nanoparticles on its photosensitized degradation in water.

The production of dichlorophen (2,2'-methylenebis(4-chlorophenol), DCP) and its use as an anthelmintic and in pesticide products result in its direct release to the environment. To the purpose of modelling the possible photodegradation routes of DCP sorbed on sediments or suspended particles, the synthesis and characterization of silica nanoparticles modified with DCP (NP-DCP) is reported. The reactivity of NP-DCP with the excited states of riboflavin, a sensitizer usually present in natural waters, and with singlet oxygen were investigated.

Triplet state of 4-methoxybenzyl alcohol chemisorbed on silica nanoparticles.

The knowledge of photochemical kinetics in colloidal systems is important in understanding environmental photochemistry on dispersed solid surfaces. As model materials for the chemically sorbed organic compounds present in natural environments, modified silica nanoparticles (NPs) were obtained here by condensation of the silanol groups of fumed silica nanoparticles with 4-methoxybenzyl alcohol. These particles were characterized by different techniques.

Generation of chemisorbed benzyl radicals on silica nanoparticles.

Functionalized silica nanoparticles (NP) were obtained by esterification of the silanol groups of fumed silica nanoparticles with benzyl alcohol. These particles were characterized by Fourier transform infrared spectroscopy, (13)C and (29)Si NMR spectroscopy, thermogravimetry, total organic carbon, Brunauer-Emmett-Teller analysis, UV-visible spectroscopy, and transmission electron microscopy. NP suspensions in water/acetonitrile mixtures were used as quenchers of benzophenone (BP) phosphorescence in time-resolved experiments at the excitation wavelength of 266 nm.

The use of molecular probes for the characterization of dispersions of functionalized silica nanoparticles.

Butoxylated silica nanoparticles (BSN) were prepared by esterification of the silanol groups of fumed silica nanoparticles with butanol and characterized by 13C and 29Si NMR and thermogravimetry. The molecular probes benzophenone (BP) and safranine-T were used to investigate the BSN suspensions in water:acetonitrile. Laser flash-photolysis experiments at lambda(exc)=266 nm performed with BSN suspended in acetonitrile:aqueous phosphate buffer supported previous results of our group obtained by time-resolved phosphorescence experiments and showed that only free and adsorbed excited triplet states of BP and diphenylketyl radicals contribute to the signals.

Photoinduced degradation of the herbicide clomazone model reactions for natural and technical systems.

The photodegradation of the herbicide clomazone in the presence of S(2)O(8) (2-) or of humic substances of different origin was investigated. A value of (9.4 +/- 0.

Trichloromethyl chloroformate ("diphosgene"), ClCOOCCl3: structure and conformational properties in the gaseous and condensed phases.

The conformational properties of gaseous trichloromethyl chloroformate (or "diphosgene"), ClC(O)OCCl3, have been studied by vibrational spectroscopy [IR (gas), IR (matrix), and Raman (liquid)] and quantum chemical calculations (MP2 and B3LYP with 6-311G basis sets); in addition, the structure of a single crystal at low temperature has been determined by X-ray diffraction. ClC(O)OCCl3 exhibits only one conformational form having Cs symmetry with a synperiplanar orientation of the C-O single bond relative to the C=O double bond. The calculated energy difference between the syn and anti forms, 5.