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This work aims at designing through a �green� bottom-up strategy, four types of bio-based systems containing artificial cell membranes (with or without vitamin C) and silver nanoparticles (AgNPs) phyto-generated from aqueous extract of Arctium lappa leaves. The �green� approaches for AgNP synthesis, by using the vast bioreducing potential of plants are low-cost and eco-friendly procedures.Exploiting vegetal wastes as precursors for phyto-metallic nanoparticles has received attention from scientific community in the last years due to its significant economic and environmental impacts. UV-Vis absorption spectra demonstrated the biosynthesis of metallic nanoparticles which exhibited a strong SPR peak located at 437 nm wavelengths. The formation of the biocomposites containing the �green� synthesized AgNPs has been demonstrated by UV-Vis absorption spectroscopy and Dynamic Light Scattering measurements. DLS results highlighted the nanoscale size of the prepared �green� AgNPs. The physical stability of the obtained silver-based systems was evaluated through zeta potential values, based on electrophoretic mobility. The systems loaded with vitamin C proved to be more stable and showed enhanced antioxidant activities (between 72.3% to 88% evaluated by chemiluminescence technique). Our results demonstrated that these developed silver-based biogenic systems generated from Arctium lappa leaves could be used as antioxidant agents in various biomedical applications.

Huge amounts of vegetable waste, mainly resulting from the food industry, need large areas for storage, as they could cause hazardous environmental impact, leading to soil and water pollution or to CO2 emissions during accidental incineration. This work was aimed at recycling certain lignocellulosic waste (walnut shells, kernels of peach, apricot, and olive) to design advanced carbon material precursors (ACMP) to be used for obtaining nano-powders with high applicative potential in pollution abatement. Both waste and ACMP were characterized using proximate and elemental analysis, and by optical microscopy. Complex characterization of raw materials by FTIR, TGA-DTG, and SEM analysis were carried out. The ACMP were synthetized at 600–700 °C by innovative microwave heating technology which offers the advantages of lower energy consumption using 3.3 kW equipment at laboratory level. The ACMP ash < 3% and increased carbon content of 87% enabled the development of an extended pore network depending on degassing conditions during heating. TEM analysis revealed a well-developed porous structure of the synthesized ACMP carbonaceous materials. Due to the presence of oxygen functional groups, ACMPs exhibit adsorption properties highlighted by an iodine index of max. 500 mg/g and surface area BET of 300 m2/g, which make them attractive for removal of environmental pollutants such as dyes having molecule sizes below 2 nm and ions with pore dimensions below 1 nm, widely used industrially and found in underground waters (NO3−) or waste waters (SO42−).

In this study, hydroxyapatite (HAp) obtained by hydrothermal synthesis from natural sources (whelk shells of Rapana thomasiana) was compared to synthetic hydroxyapatite (prepared from chemical reagents) and used for 3D printing of HAp-based structures. Rapana thomasiana can be found in Romanian coast of Black Sea. The visceral part of Rapana is used for culinary purposes, but the whelk shell, mainly consisting of CaCO3, remains as biowaste and can be used as a source of Ca for hydroxyapatite synthesis. Synthetic and natural hydroxyapatite nanopowders were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), dynamic light scattering (DLS) method and in vitro tests. XRD and FT-IR have confirmed the formation of nanostructured hydroxyapatite irrespective of the raw material used. Both types of powders were further used for 3D printing of HAp-based structures, which have also been characterized by SEM and in vitro tests. In vitro tests performed on natural HAp disks (made from whelk shell) lack cytotoxicity and were associated with cell viability similar to that for the synthetic hydroxyapatite disk.

The main purpose of the present research was to test the ability of nanostructured lipid carriers (NLCs) to efficiently host a hydrophilic polyphenol active with health-promoting activities (caffeic acid (CA)). The caffeic acid-loaded lipid nanocarriers (CA-NLCs) were obtained by high-pressure homogenization technique using a surfactant mixture of Tween 20 and L-α-phosphatidylcholine in association with a lipid mixture of linseed oil, hexadecyl palmitate, and glycerol monostearate. In the first stage, the proportion between surfactant mixture and lipid phase has been varied to obtain appropriate stable nanocarriers. The optimized NLCs have been further loaded with different amounts of caffeic acid and were analyzed in terms of physical stability, size characteristics, and encapsulation efficiency. The antioxidant activity of CA-loaded NLCs and their release behavior have been tested by specific in vitro methods, e.g., ABTS (2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) assay and release experiments, by Franz cell diffusion. The ABTS assay highlighted a high antioxidant potential of the caffeic acid in association with linseed oil. The capacity to capture ABTS cationic radicals was superior for the NLC entrapping an initial amount of 1.5% CA, the level of antioxidant capacity being 91.3%. The in vitro release experiments showed a different release behavior, depending on the initial amount of caffeic acid used. NLC loaded with a higher concentration of CA manifests a gradual slow release, e.g., 45% CA after 24 h of in vitro experiments, while the NLC loaded with smaller concentration of CA assured a higher release in time, around 65%.

This paper presents the development of dynamically cured polymer composites and nanocomposites based on plastomer - PP (polypropylene) and EPDM elastomer (ethylene-propylene-diene-terpolymer) compatibilized and reinforced with nanometric particles-MMT (montmorillonite, chemically modified layered clay) in two stages, by extrusion-granulation and mixing. Nanoparticles increase the thermal resistance of dynamically cured polymer nanocomposites. By means of compatibilization and dynamic curing, elastomer particles - EPDM are more easily dispersed in the mixture. The materials obtained were tested physicomechanically (Melt Flow Index) and morpho-structurally (FT-IR and DSC).

A comprehensive study has been carried out to evaluate the extraction of heavy metals mixture (Co2+, Cr3+, Cu2+, Ni2+) from aqueous media by Winsor II non-ionic microemulsion, containing polyoxyethylene (4) lauryl ether as non-ionic surfactant and butyl acetate as organic phase. The extraction mechanism is based on the formation of thiocyanate complexes of metals and their transfer from aqueous to microemulsion phase, either towards the interfacial film of surfactant (Co2+) or into the core of micelles (Cr3+, Cu2+, Ni2+). The value of the distribution coefficient for Co2+ was higher than for the other studied metals and its extraction efficiency was not dependent on the working conditions, showing a maximum value (99.99%) in all cases. By using successive extractions, chromium, nickel and copper ions that remained in the aqueous phase after first extraction were transported into the microemulsion phase, leading to an increase in the extraction efficiency up to 99.99% for chromium and copper, and 85% for nickel. Based on pH influence, a selective extraction of Co2+ and Cr3+ can be achieved, since the cobalt ions were completely extracted into the microemulsion phase at pH = 1, and the chromium ions still remained in the aqueous phase. Keywords: Nonionic microemulsion, Thiocyanate complexes of heavy metals, Simultaneous heavy metals extraction, Microinterfacial effect, Synergism

The paper aims at testing an innovative organic fertilizer obtained from waste by processing a mixture of marine algae biomass, sewage municipal sludge and farmyard manure. Design of this polycomposite fertilizer is based on adequate conceptual and experimental models by taking into account the complex interactions among these three biomasses. In the first step a detail physico-chemical analysis has been performed on the composition of the three raw materials and also on the soil. In the second phase similar analyses have been carried out on representative samples of soil treated with the compost as compared with untreated soil samples. Analytical methods applied were FT-IR spectroscopy in correlation with organic/inorganic and total carbon (TOC/TIC/TC) analysis. The efficiency of applying this compost on the field at large scale has been assessed by means of fatty acid content of the oleaginous plants cultivated. Based on correlation between production quality and chemical composition of the composted soil, the optimal proportions of the mixture of the three organic wastes will be selected for designing an eco-friendly fertilizer able to improve agrochemical properties of the soil.

This study aimed to examine the efficiency of novel bioactive nanostructures represented by silica–titania sieves used as carriers for a new antibacterial agent izohidrafural against bacterial strains isolated from nosocomial urinary tract infections, by using biological quantitative assays. Several release trials have been established and compared with MCM-41 in parallel experiments to achieve the optimum release profile. The obtained systems showed that silica–titania sieves loaded with izohidrafural proved to be the most active material against Klebsiella pneumoniae (average minimal inhibitory concentration [MIC] 40.62 μg/mL), desaminase-positive strains (average MIC 2.925 μg/mL), and Proteus mirabilis (average MIC 9.37 μg/mL), the last being reported with the highest growth rate in the urinary tract catheters. In contrast, the nonloaded silica–titanium sieves exhibited the highest antimicrobial activity against the Gram-positive cocci. Izohidrafural exhibited the highest antimicrobial efficiency, superior to the common drug nitrofurantoin against most Escherichia coli strains, with average MIC of 4.68 μg/mL.

Bone grafts are used in a wide array of clinical settings to augment bone repair and regeneration. This article reports a new method for the elaboration of a hybrid biomaterial in the form of sponge based on collagen gel, CaCO3 from recycled Rapana thomasiana seashell, and Na2HPO4·2H2O. Practically, collagen acts as a matrix through which calcium and phosphate ions are diffusing during in situ hydroxyapatite synthesis. The organic–inorganic interactions among biomaterial components have been studied by infrared spectroscopy, and the surface morphology was investigated by scanning electron microscopy technique. Moreover, the developed biomaterials were studied for in vitro biocompatibility with MG63 human osteoblasts. The results obtained demonstrated that the developed hybrid material does not exhibit a significant cytotoxicity and supports cell proliferation. Consequently, it holds great promise for applications in bone tissue engineering.

A class of fluorescent Au@SiO2 and SiO2@Au core–shell fluorescent nanoparticles has been synthesized using microemulsion assisted sol–gel method coupled with photoreduction reaction as an easy, rapid and versatile “one-pot” procedure. In the case of Au@SiO2-RhB (gold nanoparticles core coated with silica-Rhodamine B shell) different silica shell sizes were obtained ranging from 3 to 116 nm, while for RhB-SiO2@Au (Rhodamine B-silica core coated with gold nanoparticles shell) the size of gold shell falls within 3–38 nm interval. The synthesized core–shell nanoparticles have been characterized by a variety of techniques including Dynamic Light Scattering (DLS), High-Resolution Transmission Electron Microscopy (HR-TEM) coupled with Energy-Dispersive X-ray spectroscopy (EDX), Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD) and UV–VIS–NIR spectroscopy to confirm the size, shape, stability and topographic structure of the both core–shell nanostructures. The fluorescence enhancement of Rhodamine B (RhB) dye in the presence of gold nanoparticles (AuNPs) was demonstrated for the core–shell nanostructures synthesized in the present study, for different silica or gold shells. These interesting fluorescent core–shell nanoparticles provide ideal candidates for a variety of applications in materials science, biology, catalysis and optical fields.

Effective low cost photoactive adsorbent materials (∼90% efficiency, 0–60 mg L−1 dye loading), under sunlight irradiation, at a very low content of functional components (0.13% ZnO and 0.02% Au), were designed by incorporating ZnO and Au nanoparticles as synergistic couple in silica matrix. The tandem Au/ZnO dispersed into silica matrix formed a Schottky barrier in this type of structure and thus the band gap energy was reduced to 2.25 eV and the photocatalytic activity under visible light irradiation was increased. Highly homogeneous distribution of ZnO quantum dots (4 nm) and gold plasmons (7 nm) into the silica matrix, by a convenient “one-pot” synthesis way, namely microemulsion assisted sol–gel procedure was reported. The study of how the Au/ZnO ratio (0.01/1, 0.1/1 and 1/1) affects the silica based materials activity was evaluated and the optimal Au/ZnO ratio (0.1/1) was established. The silica network formed around the Au and ZnO nanoparticles which were confined within the microemulsions colloidal aggregates, improved the stability of the final materials in different environments and the direct contact between dye and Au–ZnO couple. Tandem adsorption and photodegradation processes, following a first order kinetics, described the path ways and mechanism of interaction between dye molecules and materials surface.

This book is a reference work focused on the role and interactions of nanoparticles and free radicals that are responsible for oxidative and endoplasmic reticulum (ER) stresses, with deep insights into the intimate mechanisms of their ecotoxicology, cytotoxicity, nanotoxicity, and genotoxicity.

The interactions of two ionic dyes, Crystal Violet and Methyl Orange, with different charged surfactants and also with a nonionic surfactant were investigated using surface tension measurements and visible spectroscopy in pre-micellar and post-micellar regions. It was found that for the water dominant phase systems the dye was localized between the polar heads, at the exterior of the direct micelle shells for all the systems. For the oil dominant phase systems, in case of the same charged dye/surfactant couples, the dye was localized in the micelle shell between the hydrocarbon chain of the surfactant nearby the hydrophilic head groups while for nonionic surfactant and oppositely charged dye/surfactant, localization of dye was between the oxyethylenic head groups towards the interior of the micelle core. Mixed aggregates of the dye and surfactant (below the critical micellar concentration of cationic surfactant), dye-surfactant ion pair and surfactant-micelles were present. The values of equilibrium constants (for TX-114/MO and TX-114/CV systems were 0.97 and 0.98, respectively), partition coefficients between the micellar and bulk water phases and standard free energy (for the nonionic systems were −12.59 kJ/mol for MO and −10.97 kJ/mol for CV) were calculated for all the studied systems. The partition processes were exothermic and occurred spontaneously.

In this study, two issues commonly associated with phytochemical based nanotechnology were addressed: (1) the use of active compounds from medicinal herbs as functional ingredients entrapped into lipid-based nanocarriers; (2) the safety and efficacy of phytochemical-based nanocarriers with promising antioxidant and antitumor benefits. In this context, nanostructured lipid carriers (NLC) based on raspberry seed oil (Rso), pomegranate seed oil (Pso) and rice bran oil (Rbo) were synthesized and proven to be highly effective for the entrapment of hydrophilic ivy leaves extract (Ile). The size, morphology, zeta potential, entrapment efficiency and crystallinity of the Ile-loaded NLC were characterized. The effectiveness of Ile loaded-NLC has been proved by identifying a high capacity to scavenge free oxygen radicals (i.e. between 94 and 98%). 200 μg mL−1 Ile-NLC based on Rbo showed no significant effects on cellular viability in the fibroblast L929 cell line, while the tumor B16 cell line was markedly affected. MTS, RTCA assays and apoptosis examination revealed that these nanocarriers induce cytotoxicity and apoptosis in the murine melanoma B16 cell line. This study reports the first evidence of the association of hydrophilic and lipophilic phytochemicals in the same lipid nanocarriers, which appears to be a promising antioxidant and antitumor approach deserving further investigation.

Drug delivery systems based on natural drug carriers have become important due to their non-toxicity and biodegradability. We report here the synthesis and characterization of new biomaterials like sponges containing collagen, chloramphenicol and glutaraldehyde for dentistry. All sponges favour water absorption, showing that increasing the glutaraldehyde content leads to an increase in water uptake. The sponges showed resistance to collagenase degradation and strong activity against the tested bacteria. Kinetic data showed non-Fickian diffusion behaviour with a slow release rate. Taking into account that dental drug delivery systems exhibit low water absorption, slow drug release, high content of drug delivery, good antimicrobial activity, and resistance to enzymatic action, the results obtained in this study indicate the optimal content of glutaraldehyde for the sponge as being 0.5%. The properties of the designed formulations demonstrate that these sponges could be adequate for the treatment and/or the prophylaxis of infected lesions at the dental level.

The combination of basil oil, natural antifungal, and nystatin has the potential to prevent the extension of topical fungal infections towards systemic infections. The aim of this study was to develop formulations based on basil oil and nystatin with the desired antifungal and antioxidant activity and low toxicity by using lipid nanocarriers. The synthesized nanocarriers showed spherical and homogeneous particles with main diameters less than 150 nm, as determined by TEM. The scanning calorimetric study revealed an imperfect crystallization in the core of lipid nanocarriers. Quantitative results suggested that basil oil concentration affects encapsulation efficiency. The prepared nanocarriers guaranteed an increased nystatin encapsulation by using 3% basil oil content. Chemiluminescence assay proved that the protective activity against oxygen free radicals was influenced by nystatin concentration. The in vitro antifungal studies revealed a better activity of the nanocarriers loaded with 1% nystatin in comparison with 0.5% loading.

The principal aim of the present study was to develop new safe and highly antioxidant nanostructured lipid carriers loaded with sea buckthorn extract. Three vegetable oils — grape seed oil, sea buckthorn oil and St. John's wort oil ( Hypericum perforatum oil) — were used as matrix components and the modified high shear homogenization technique has been employed for the synthesis of nanostructured materials. The effect of these oils on the antioxidant and antimicrobial activities of loaded sea buckthorn extract — nanostructured lipid carriers — has also been studied. For this purpose, a combination of two solid lipids: cetyl palmitate with glyceryl stearate and lecithin/block copolymer has been used. The obtained nanostructured lipid carriers have been characterized for the particle size and zeta potential by means of dynamic light scattering measurements. The nano-dimension morphology of loaded nanostructured lipid carriers was confirmed by transmission electron microscopy. Their crystallinity measured by differential scanning calorimetry has revealed a high disordered lipid matrix. The properties of sea-buckthorn-extract-loaded nanoparticles have been evaluated by an appropriate in vitro analysis (chemiluminescence method). The presence of the three vegetable oils influences extensively the antioxidant properties of the developed nano-formulations, as has been demonstrated using the chemiluminescence technique. The antimicrobial activity of the studied nanostructured lipid carriers, analyzed by the diffusion disc method, shows in most of the samples a high efficiency against Escherichia coli bacteria.

Due to their unique features, most nanostructured lipid carriers (NLCs) in association with vegetable oils that exhibit UV filtering properties and bioactivity could be used in many cosmetic formulations. Therefore, in this work, a new application of pomegranate seed oil (PSO) in the cosmetic sector was developed, based on the synthesis of bioactive lipid nanocarriers loaded with various UV filters by the hot high pressure homogenization technique. To get broad spectrum photoprotection, different UVA and UVB filters have been used (Avobenzone — AVO, Octocrylen-OCT, Bemotrizinol — BEMT). The influence of the solid lipids combined with PSO on the particle size, physical stability and entrapment efficiency was investigated using 8 nanocarrier systems. An improved physical stability and an appropriate size were obtained for NLCs prepared with Emulgade, carnauba wax and PSO (e.g. −30.9÷-36.9 mV and 160÷185 nm). NLCs showed an entrapment efficiency above 90% and assured slow release rates of UV filters, especially for BEMT (5%). The developed nanocarriers have been formulated into safe and effective sunscreens containing low amounts of synthetic UV filters coupled with a high percent of natural ingredients. The highest SPF of 34.3 was obtained for a cream comprising of 11% PSO and 3.7% BEMT

After oxidation of tannins (Tannins 1–3) extracted from grape seeds, Tanoxil compounds with increased solubility and enhanced antioxidant activities were synthesized. In this research, ABTS+· assay and a chemiluminescence method were used for antioxidant measurement of hydrophilic compounds (Tanoxils 1–3).It was observed that the antioxidant activity (AA, %) is very similar for the three samples, while at the same time AA is quite high (93.16%–96.48%). The percentage of inhibition by ABTS+· is higher for Tanoxil 2 (96.4%) as compared to Tannin 2 compound (14.34%). Moreover, the total content (TCF) of carboxyl and phenolic groups was investigated. TCF values, determined for Tanoxil products, revealed a double (Tanoxil 1) or triple (Tanoxil 2) increase as compared to the value of the TCF of Tannin 1. Tanoxil products represent an interest for future research as they have a high AA (96.4%) and the content of acidic groups is significant (TCF, 0.191 meq g−1).

In this paper, the preparation and characterization of some novel nanostructured lipid carriers for drug delivery are reported. They are obtained by mixing two solid lipids, cetyl palmitate and glyceryl stearate, with three types of vegetable oils: grape seed oil, St. John's wort oil ( Hypericum perforatum oil) and sea buckthorn oil. In order to increase their antioxidant and antimicrobial properties, they are co-loaded with green tea extract by using a modified high shear homogenization technique. Size distribution and polydispersity index of the developed nanostructured lipid carriers determined by the dynamic light scattering, and corroborated with the results obtained by the transmission electron microscopy analysis, confirmed that the structures obtained are at nanoscales. The crystallinity behavior of the prepared nanostructured lipid carriers has been studied by differential scanning calorimetry; zeta potential measurements show that all loaded nanostructures present excellent physical stability. Their antioxidant and antimicrobial properties evaluated by an appropriate in vitro analysis using the chemiluminescence method, and the diffusion disc method, respectively, show that green tea extract could be utilized as a valuable natural source of antioxidant and antimicrobial agent. These new nano-formulations proved to have significant potential for nutritional and pharmaceutical applications.

A systematic study of the design and characterization of silica-microemulsion templates is presented. The ternary phase diagrams in micro-heterogeneous systems, by using a non-ionic surfactant (Brij 30) and different silica precursors (MTEOS, TEOS, PTEOS), have been drawn. Based on Khalweit diagrams, the phase inversion temperature was estimated as close to 315 K, for both alchil (TEOS) and aril (PTEOS) types of alcoxides. By correlating the information obtained from phase diagrams at room temperature with that of size effects revealed by VIS absorption molecular probes (bromthymol blue dye), the phase inversion point, i.e. the transition point from water-in-oil to oil-in-water microemulsion, was also clearly established as corresponding to R ∼ 1. Besides technically attractive features such as a wide variety of inorganic and hybrid nanomaterials, high specific surface and highly efficient applicative properties of the final materials, the approach of silica-microemulsion-based templates can be seen as a route towards the Green Chemistry concept.

The aim of this research was to develop advanced lipid nanocarriers based on renewable vegetable resources (rice bran oil and raspberry seed oil) that possess self-antioxidative properties, having advantages in terms of minimal side effects and exhibiting the ability to simultaneously co-encapsulate and co-release two active compounds. The focus has been oriented towards developing safe cosmetic formulations with broad-spectrum photoprotection based on these new lipid nanocarriers that contain large amounts of vegetable oils and low concentrations of synthetic UVA and UVB filters (butyl-methoxydibenzoylmethane - BMDBM and octocrylene - OCT). The lipid nanocarriers have a spherical shape and show good physical stability, with a zeta potential in the range of -25.5 to -32.4 mV. Both vegetable oils play a key role in the preparation of efficient nanocarriers, leading to a less ordered arrangement of the lipid core that offers many spaces for the entrapment of large amounts of BMDBM (79%) and OCT (90%), as wells as improved antioxidant activity and UV absorption properties, particularly for the lipid nanocarriers prepared from rice bran oil. By formulating the lipid nanocarriers into creams containing only 3.5% of the UV filters and 10.5% of the vegetable oils, the resulting sunscreens exhibited improved photoprotection, reflecting up to 91% and 93% of UVA and UVB rays, respectively. A new direction of research achieved by this study is the multiple release strategy of both UV filters from the same lipid nanocarrier. After 24 hours, a slow release of BMDBM (less than 4%) and OCT (17.5%) was obtained through a Fick diffusion process. This study demonstrates a significant advance in the areas of both nanotechnology and cosmetics, developing safer cosmetic formulations that possess broad antioxidant, photoprotective and co-release effectiveness due to the existence of a high content of nanostructured vegetable oils combined with a low amount of synthetic UV filters in the same carrier system.

Novel cross-linked hydrogels were synthesized as potential materials for the development of smart biofertilizers. For this purpose, hydrogels were prepared using collagen hydrolysate recovered from tannery waste. The water-soluble polymer poly(sodium 4-styrenesulfonate-co-glycidyl methacrylate) (P(SSNa-co-GMAx)) was among others used for the cross-linking reaction that combined hydrophilic nature with epoxide groups. The synthetic procedure was thoroughly investigated in order to ensure high percentage of epoxide groups in combination with water-soluble behavior. The copolymer did not show cytotoxicity against normal lung, skin fibroblasts, or nasal polyps fibroblasts. Through the present work, we also present the ability to control the properties of cross-linked hydrogels by altering copolymer&rsquo, s composition and cross-linking parameters (curing temperature and time). Hydrogels were then studied in terms of water-uptake capacity for a period up to six days. The techniques Proton Nuclear Magnetic Resonance (1H NMR), Thermogravimetric Analysis (TGA), Size Exclusion Chromatography (SEC), and Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) were applied for the characterization of the synthesized copolymers and the cross-linked hydrogels. Three samples of biofertilizers based on collagen hydrolysate functionalized with P(SSNa-co-GMAx) and starch and having nutrients encapsulated (N, P, K) were prepared and characterized by physical&ndash, chemical analysis and Energy Dispersive X-ray analysis-Scanning Electron Microscope (EDAX-SEM) in terms of microstructure. Preliminary tests for application as fertilizers were performed including the release degree of oxidable organic compounds.

Collagen sponges are known to be safe and well-characterized supports for drug delivery systems. The aim of this study was to prepare, characterize and test drug delivery systems that contain collagen as support and niflumic acid as a drug. Type-I collagen and niflumic acid gels were cross-linked with different concentrations of glutaraldehyde and then freeze-dried in order to obtain collagen matrices (spongious form). The physical-chemical properties were assessed by infrared spectroscopy (FTIR) and morphological properties were evaluated by water absorption. Niflumic acid release from cross-linked collagen spongious forms was also investigated and the kinetic mechanism was discussed.

Due to their spectral characteristics, phototoxicity and high affinity for tumour tissues, porphyrins and their derivatives are widely used in modern medicine as contrast agents for cancer diagnostics and as sensitizers in photodynamic therapy, where they kill tumours via enhancement of tumour oxidative stress. The aim of this work was to simulate in vitro the effects caused by oxidation of two free base porphyrins, 5,10,15,20-tetraphenylporphyrin (TPP) and 5,10,15,20-tetra(4-methoxyphenyl)porphyrin (TMOPP). The kinetic study was monitored using spectral techniques and chemiluminescence. The effect of both porphyrins on an oxidation process was evidenced using the chemiluminescent system, luminal-hydrogen peroxide, in a phosphate buffer at pH 7. It was found that at low concentration, TPP exerts the anti-oxidative effect in the employed chemiluminescent system, while at higher concentrations, its effect is pro-oxidative. TMOPP exerts a pro-oxidant effect, which was more pronounced than TPP. The results are discussed with respect to oxidative stress.

Synthesis of some novel fluorescence nanomaterials loaded with photoactive polyphenols originated from plants with a high spectrum of biological activity, by replacing synthetic chemicals, may open new opportunities for optical and bio-medical applications. This paper presents the synthesis, characterization and fluorescence properties of a new class of materials based on host hybrid matrices obtained through templated sol–gel route, by hydrolysis and co-condensation of tetraorthoethylsilicate with octaisobutyltetracyclo [7.3.3.15,11] octasiloxane-endo-3,7-diol. The aim of paper is focused on the evaluation of the behavior of the fluorescence properties of ornamental bush extract at immobilization in a templated silica matrix and in a silica-silsesquioxane network, using as templates a neutral, non-toxic and biodegradable surfactant from poly(ethyleneglycol) class and a high biocompatible non-surfactant from glucidic class. The proofs of ornamental bush extract entrapment by physical interactions in silica based networks were provided by FT-IR and UV–VIS spectroscopy. The changes of polymer network due to the hydrogen bond interactions between residual Si–OH groups and functional groups of organic molecules from extract were evidenced by shifts of specific vibrations. In UV–VIS-NIR domain, the chromophore groups from ornamental bush extract were also evidenced by similar small shifts. As a result of ornamental bush extract entrapment, in all the immobilized samples the fluorescence intensity was more than 10 times amplified in samples templated with poly(ethylenglycol) surfactant) and of about 5 times in samples with glucidic template due to the physical adsorption of polyphenolic molecules from extract, excellent synergistic optical properties of SiO2 and silsesquioxane compound and also due to a favorable conformational arrangement. The size of synthesized polymeric materials, estimated by dynamic light scattering technique showed main diameters less then 1.4 μm, namely 1,060 and 211 nm—for samples with d-glucose template and 1,330 and 531 nm—for samples with poly(ethyleneglycol) template, respectively, with a narrow size distribution and a polidispersity varying between 0.022 and 0.426. These results are in good accordance with TEM images that evidenced the presence of some polymeric aggregates which contain the vegetal extract immobilized inside hybrid SiO2-Sq polymeric network of about hundred nanometers size. This study bring new contributions to the development of the sol–gel procedure by entrapment of a complex vegetable mixture in polymeric matrices as integral component of silica and hybrid silica-silsesquioxane networks which leads to a significant enhancement of the functional properties of the final material, thus diversifying the potential applications of organic doped sol–gel glasses.

New complexes of Cu(II) with some substituted 2-(3,5-dimethyl-pyrazol-1-yl)-methyl-acetanilides (L) hae been synthesized. The complex compounds, CuL4X2 (where X- = Cl,Br, CH3COO) were characterized by elemental analysis, as well as IR, UV-VIS, EPR spectroscopy. The study evidenced the influence of the position of the methyl group on the benzene ring and also of the anions on the physical properties of the compounds.

Since their discovery, fullerenes in general and buckminsterfullerene C60 in particular, became a subject of great interest for studies. Being compatible with the sol–gel process, one of the promising approaches is to incorporate the fullerene molecules in sol–gel oxide matrices. Great part of studies deals with SiO2 sol–gel oxide as the optimal matrix for entrapment of organic molecules. C60-doped silica matrices used through our present study have been prepared by sol–gel processing, using different alkoxide precursors, as a silicon oxide source: tetraethoxysilane (a), methyltriethoxysilane (b), phenyltriethoxysilane (c) and a mixture of phenyltriethoxysilane and tetraethoxysilane (d). C60-to-Si molar ratio was chosen to be 1.0 × 10−3:1 for all materials synthesized, final oxide composition remaining unchanged in all cases. The effect of ultrasounds on the gelation process was established by preparing two series of samples, either via sonication or in the absence of ultrasound processing. The properties of the resulted materials were also established. The prepared samples were characterized by XRD, IR, RPE and UV-VIS spectrometry. All methods have put in evidence the embedment of the fullerene into the silica matrix.

Metal complexes ML2Cl2, where M is Fe(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) and L is Schiff base formed by condensation of 2-thiophenecarboxaldehyde and 2-aminopyridine, N-[2-thienylmethylidene]-2-arninopyridine (TNAPY), have been prepared and characterized by elemental analysis, magnetic and spectroscopic measurements. IR and NMR spectra show that the nitrogen of the azomethyne group and the sulphur of the thiophene ring take part in coordination. Magnetic, ESR and electronic spectral studies show a distorted octahedral structure for the Fe(II), Co(II), Ni(II) and Cu(II) complexes and a tetrahedral geometry for the Zn(II) and Cd(II) complexes. Conductance measurements suggest the non-electrolytic nature of the complexes, with the exception of the Zn(TNAPY)2Cl2 and Cd(TNAPY)2Cl2 compounds which are 1:2 electrolytes.

Composite SiO2-iron oxide materials were prepared by three experimental procedures. In the first case (1), the iron oxides were precipitated during the sol-gel process. In the second case (2), the SiO2 matrix was initially obtained, and the iron oxides were formed by thermal treatment after impregnation of a soluble Fe2+ salt in the previously processed matrix. In the third method (3), ferrite powders, prepared by wet chemical method, were embedded into a SiO2 based sol-gel matrix. Two type of precursors (tetraethoxysilane (TEOS) or methyltriethoxysilane (MTEOS) were used as SiO2 sources. Various properties versus both type of precursor and on the method of preparation were noticed. Materials with high porosity and nano-sized iron oxide content could be prepared using the mentioned above methods.

International audience; This paper presents the extractive technological process and processing of the selective vegetal extracts from the Rosmarinus officinalis L. species in order to obtain some vegetal bioproducts with proven antioxidant activity. By combining various active fractions, new vegetal bioproducts have been obtained and have been physically and chemically characterised (infrared, ultraviolet visible spectroscopy, chemiluminescence, determination of flavonoids, polyphenols, and polyphenolcarboxilic acids content) and finaly biologically tested. The antioxidant activity of Rosmarinus officinalis extracts have been evaluated by two techniques, in vitro chemiluminescence and ex vivo biological tests, both of them recommending the vegetal bioproducts for prophylactic and therapeutic purposes.

highlights � Soft and functional nanocarriers based on Pumpkin and Amaranth oils are achieved. � In vitro antioxidant activity was superior for nanocarriers based on Amaranth oil. � Co-loaded vegetable nanocarriers have greatly improved the photoprotective effect. � Avobenzone and Octocrylen were co- released from nanocarriers in a prolonged manner. � The co-loaded nanocarriers have been formulated into advanced cosmetic prototype. graphical a bstract a. The cubic shape of vegetable - lipid nanocarriers; b. The photoprotective properties of vegetable nano- carriers co-loaded with 3% AVO and 7.5% OCT; c. Effect of UV irradiation of cosmetic prototypes based on vegetable co-loaded nanocarriers (3.75% OCT and 1.5% AVO) abstract The general objective is to design and synthesize soft and functional nanocarriers based on vegetable oils (Pumpkin and Amaranth oils) able to co-encapsulate and co-deliver two UV-A and UV-B filters (Avobenz- one, Octocrylen) and to explore their efficiency in developing advanced bio-cosmetic prototypes. The exploitation of vegetable oils with safe utilization and biological efficiency in obtaining soft nanocarriers represent an innovative approach that provides a significant advance in the nanotechnology field. The obtained vegetable nanocarriers having mean diameters of 100 and 160 nm were tested in vitro for their antioxidant, photoprotective and drug release properties. The in vitro ability to capture free radicals was superior when the nanoparticles were prepared in Amaranth oil/solid lipids system. Study of UV absorb- ing effect revealed that co-loaded vegetable nanoparticles have greatly improved the photoprotective properties, the obtained SPF being of 40-45 and FP-UVA of 27-34. These values are associated with a high protective effect, e.g. more than 99% against UV-B and 92% against UV-A radiation. In vitro co-release experiments demonstrated that both Avobenzone and Octocrylen filters were released in a prolonged manner. The ultimate objective was to formulate the newly co-loaded nanoparticles into advanced cos- metic prototype and compare it with conventional cream. The soft vegetable-nanocarriers produced sig- nificantly higher UV-protection than the conventional cream. The use of appropriate renewable vegetable sources for obtaining soft bio-active nanostructures with broad health benefices has the potential to sat- isfy both the industrial and consumer needs, thanks to their safety and sustainability.

Tailoring nature is a continuous rediscovered paradigm of scientific community despite of the so called ‘independence of the artificial creations’ of the new age of technology. The last century discoveries in terms of chemistry science achievements could be easily projected into a design of a perfect elliptic model in continuing creation related to report to nature: an imaginary circle which never close to its natural model, even those new circles became asymptotic smaller and smaller to the imaginary point of model.

International audience; Near-infrared spectral analysis was useful to quantify the ester content of chemically modified cellulose and lignocellulosics. Two kinds of samples were studied, as long aliphatic-chain cellulose esters and wood sawdust chemically-modified either by anhydrides or by ethylene carbonate. It was possible to determine the degree of substitution (DS) of such samples through a correlation by partial least square (PLS) of second-order derivative of NIR spectra. This technique was efficient even when DS values were low, which is difficult to do by using FTIR. It was also possible to distinguish reagent molecules that were attached to the cellulosic substrate by hydrogen bonding from those linked by covalent bonding.

International audience; The possibility of obtaining copper ferrite through the thermal decomposition of the two polynuclear coordination compounds: (NH4)8[Fe2Cu(C2O4)8] (I) and [Fe2Cu(C2O4)2(OH)4]*4H2O (II) was considered. The polynuclear compounds were characterized by various physical chemical techniques, e.g., IR, UV-VIS, EPR, Mössbauer spectra, thermal analysis and magnetic measurements. The final products obtained after thermal decomposition of the complex compounds were analysed by X-ray diffraction. A mixture of tetragonal CuFe2O4, α-Fe2O3 and CuO is generated from the thermolysis of compound I, while a clean tetragonal CuFe2O4 with saturation magnetization of 26.89 emu g−1 is obtained from compound II.

University of Bucharest, Faculty of Chemistry, Inorganic Chemistry Laboratory, Str. Dumbrava Rosie nr. 23, 70254-Bucharest, Romania University Politehnica Bucharest, Faculty of Industrial Chemistry, Str. Polizu nr. 1, 78126-Bucharest, Romania Institute of Physical Chemistry, Coordination Chemistry Laboratory, Spl. Independentei nr. 202, 77208-Bucharest, Romania Manuscript received 2 March 2000, revised 18 October 2000. accepted 10 February 2001 Some new complexes of CrIII, CoII, NiII, CuII and CdII have been synthesized with a tetradentate Schiff base, glyoxilidenc-bis-2-aminoethylpyridine. An octahedral geometry has been proposed for the CrIII and NiII complexes and tetrahedral geometry for the rest of the compounds.&nbsp

The efficiency of a cosmetic product depends not only on the active ingredients, but also on the carrier system devoted to improve its bioavailability. This article aims to encapsulate two couples of UV molecular absorbers, with a blocking action on both UV-A and UV-B domains, into efficient lipid nanoparticles. The effect of encapsulation on the specific properties such as sun protection factor and photostability behaviour has been demonstrated. The lipid nanoparticles with size range 30-350 nm and a polydispersity index between 0.217 and 0.244 are obtained using a modified high shear homogenisation method. The nanoparticles had spherical shapes with a single crystallisation form of lipid matrices characteristic for the least ordered crystal structure (α-form). The in vitro determination of photoprotection has led to high SPF ratings, with values of about 20, which assure a good photoprotection and filtering about 95% of UV radiation. The photoprotection effect after irradiation stage was observed to be increased more than twice compared to initial samples as a result of isomerisation phenomena. All the results have shown that good photoprotection effect and improved photostability could be obtained using such sunscreen couples, thus demonstrating that UV absorbers-solid lipid nanoparticles are promising carriers for cosmetic formulations.