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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−).

This work is focused on obtaining antioxidant materials based on liposomes and silver nanoparticles (AgNPs). The lipid vesicles labeled with chlorophyll a (as a spectral marker) were prepared by li...

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 treatment of wastewaters with complex load including dyes and heavy metals is a subject of paramount importance since trace amounts of these compounds lead to an enormous pollution problem. The present research proposes an innovative, fast and efficient microemulsion system for simultaneous extraction of a mixture of dyes (Crystal violet and Rhodamine B) and heavy metals (cobalt(II) and copper(II) ions) from such wastewaters. The used microemulsion is an environmental friendly system containing Brij 30 as nonionic surfactant and butyl acetate as organic phase. The effect of various parameters with significant influence on the dye and metals extraction efficiencies has been investigated in order to find out the optimal compositions for an efficient extraction of dyes – heavy metals mixture from aqueous media. The results show that the optimum extraction conditions for this system corresponds to pH = 5, a water to oil volumetric ratio equal to 9 and a concentration of the complexing agent equal to 2 mol/L.

The efficiency of a new eco-friendly microemulsion system based on Polyoxyethylene (4) Lauryl ether/Butyl acetate/Water was compared to that of Polyoxyethylene (4) Lauryl ether/Ethyl acetate/Water. The two systems were analyzed with respects to the recovery of monocomponent or multicomponent targeted hydrophilic compounds (Crystal Violet dye and Co2+ ions) from polluted liquid media. In order to determine the optimal recovery conditions, the influence of surfactant and dye concentrations on the volumetric ratio of aqueous phase to microemulsion (F) was studied. Furthermore, heavy metal concentrations and distribution coefficients were analyzed using the ternary and pseudo-ternary phase diagrams. The results showed that the Polyoxyethylene (4) Lauryl ether/Butyl acetate/Water system was more efficient compared to the Polyoxyethylene (4) Lauryl ether/Ethyl acetate/Water system in the recovery of hydrophilic compounds for both monocomponent (Crystal Violet dye or Co2+) and multicomponent (Crystal Violet dye and Co2+) systems. A recovery efficiency of 90.6% for dye and heavy metal ions was obtained using the Polyoxyethylene (4) Lauryl ether/Butyl acetate/Water microemulsion system.

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.

The growing scientific interest in exploitation of vegetable bioactives has raised a number of questions regarding their imminent presence in pharmaceutical formulations. This study intends to demonstrate that a dual combination between vegetable oil (e.g. thistle oil, safflower oil, sea buckthorn oil) and a carrot extract represents an optimal approach to formulate safe carrier systems that manifest cell regeneration effect and promising antioxidant and anti-inflammatory activity. Inclusion of both natural actives into lipid carriers imparted a strong negative charge on the nanocarrier surface (up to -45mV) and displayed average sizes of 70nm to 140nm. The entrapment efficiency of carrot extract into nanostructured carriers ranged between 78.3 and 88.3%. The in vitro release study has demonstrated that the entrapment of the extract represents a viable way for an equilibrated release of carotenoids. Besides the excellent antioxidant properties (e.g. scavenging up to 98% of the free oxygen radicals), the results of cellular integrity (e.g. cell viability of 133%) recommend these nanocarriers based on dual carrot extract-bioactive oil as a promising trend for the treatment of certain disorders in which oxidative stress plays a prominent role. In addition, the lipid nanocarriers based on safflower oil and sea buckthorn oil demonstrated an anti-inflammatory effect on LPS induced THP-1 macrophages, by inhibiting the secretion of two pro-inflammatory cytokines, IL-6 and TNF-α.

Incorporating noble metal nanoparticles (NPs) and oxides has been proved to be an effective method to tune the optical properties of silica based materials. In this paper the optical and photocatalytic properties have been studied for ZnO/SiO 2 modified with Au or NiO nanoparticles. Changes in the optical properties of semiconductor ZnO particles have been observed due to the deposition of coloured Au and NiO nanoparticles by reducing the band gap energy and thus extending light absorption to visible domain. The excellent surface characteristics of NiO/ZnO/SiO 2 and Au/ZnO/SiO 2 favour the adsorption behaviour of these materials and limit the recombination of electron–holes pairs. Crystal Violet degradation under VIS light proved to have higher efficiency in the presence of Au/ZnO/SiO 2 (97%) than for NiO/ZnO/SiO 2 (60%).

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.

Pollution abatement of wastewaters discharged from textile industry remained a serious environmental problem susceptible for further technological improvements. This study proposes an innovative, fast and efficient microemulsion system for removal of ionic dyes mixture from such wastewaters. A series of physical–chemical parameters (initial dye concentration, pH, salt and sequestrant concentrations) with significant influence on the dye removal efficiency of water/nonionic surfactant/ethyl acetate ternary system has been studied in order to find out the optimal compositions for an efficient extraction of cationic and anionic dyes from aqueous media. The optimum extraction conditions for this system correspond to pH > 5, surfactant concentration around 8% (w/w) and organic phase concentration around 13% (w/w), resulting in extraction efficiencies around 90%. By adding sodium chloride (concentration > 60 g/L) in the ternary system the removal efficiency was improved.

The work aims to simulate in vitro the antioxidant activity of four phytoestrogen type isoflavones, whose effects are closer to those of estradiol (daidzein, formononetin, genistein, biochanin A) in biomimetic environments (in lecithin lipidic bi-layers and on silver nanoparticles), using the chemiluminescent system luminol–hydrogen peroxide, in phosphate buffer, pH 7.4. The contribution of a carrier protein, human serum albumin (HSA), to the antioxidant activity of these isoflavones has also been investigated. The rate of the fluorescence quenching of HSA by isoflavone as well as the binding constant of isoflavone to HSA, in both lecithin lipidic bi-layers and on silver nanoparticles, has also been investigated by fluorescence spectroscopy. The results are discussed with relevance to the oxidative stress process.

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.

The study describes an ideal approach to increase the co-encapsulation of two water and lipid-soluble drugs in the same delivery system. The main purpose is represented by the exploitation of oil fractions isolated from amaranth seeds for the development of squalene-based nanocarriers able for a dual release of one antitumor drug, pemetrexed and one bio-flavonoid, hesperidin. The co-encapsulated nanocarriers presented unique nanoassembly morphology and showed excellent stability against aggregation. A delimited repartition of both actives, mainly in oily nanoconfinements of lipid nanocariers has been indicated by scanning calorimetry. The entrapment efficiency study revealed a great encapsulation effect with values reaching 94% for hesperidin and 89% for pemetrexed. These values are associated with a high ability of squalene-nanocarriers to capture free radicals. The greatest antioxidant activity was determined for nanocarriers that co-encapsulate 1.4% drugs, e.g., 97.3 and 98.2%. In vitro co-release tests demonstrated that pemetrexed and hesperidin were gradually released despite of their different lipophilicity. The most concentrated squalene fraction assures a slower release of both actives. The cumulative results showed that the applied strategy is a promising approach to improve the performance of medical treatments used to prevent and treat diseases associated with tumor and oxidative stress.

The development of nano-dosage forms of phytochemicals represents a significant progress of the scientific approach in the biomedical research. The aim of this study was to assess the effectiveness of lipid nanocarriers based on natural oils (grape seed oil, fish oil and laurel leaf oil) in counteracting free radicals and combating certain tumor cells. No drug was encapsulated in the nanocarriers. The cytotoxic effect exerted by bioactive nanocarriers against two tumor cells, MDA-MB 231 and HeLa cell lines, and two normal cells, L929 and B16 cell lines, was measured using the MTT assay, while oxidative damage was assessed by measuring the total antioxidant activity using chemiluminescence analysis. The best performance was obtained for nanocarriers based on an association of grape seed and laurel leaf oils, with a capacity to scavenge about 98% oxygen free radicals. A dose of nanocarriers of 5mg·mL(-1) has led to a drastic decrease in tumor cell proliferation even in the absence of an antitumor drug (e.g. about 50% viability for MDA-MB 231 cell line and 60% viability for HeLa cell line). A comparative survival profile of normal and tumor cells, which were exposed to an effective dose of 2.5mg·mL(-1) lipid nanocarriers, has revealed a death rate of 20% for normal B16 cells and of 40% death rate for MDA-MB 231 and HeLa tumor cells. The results in this study imply that lipid nanocarriers based on grape seed oil in association with laurel leaf oil could be a candidate to reduce the delivery system toxicity and may significantly improve the therapeutic efficacy of antitumor drugs in clinical applications.

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.

Vegetable oils are well-known for their beneficial health effects, mainly due to their antioxidant activity, which is maintained or enhanced when they are encapsulated at nanoscale. This study aims to design new nanostructured lipid carriers (NLCs) containing various vegetable oils and their combinations in order to obtain efficient formulations with UV protection performance and antioxidant activity. Pomegranate seed oil, wheat germ oil, blackcurrant seed oil, sesame seed oil, carrot root oil, raspberry seed oil and rice bran oil were used for obtaining NLCs, as carriers for a photoprotective agent that absorbs the UVA radiation: diethylamino hydroxybenzoyl hexyl benzoate. The NLCs were characterized by mean particle size, physical stability over time, and entrapment efficiency of the UVA filter. The UV protection performance was assessed using both in vitro sun protection factor (SPF) and the UVA protection factor (UVAPF). The antioxidant activity was determined by chemiluminescence analysis. All vegetable oils used led to the development of appropriate NLCs, having mean particle sizes ranging between 100 nm and 145 nm and good physical stability with zeta potential values less negative than −35 mV. The UV protection factors were evaluated on the individual vegetable oils and on cream formulations based on NLCs. Out of the seven cream formulations, the best UV protection was assured by the pomegranate seed oil based cream resulting in a SPF of 4.1 and an UVAPF of 7.8. Knowing that a synergistic interaction can occur among the active compounds of different oils, new NLCs were developed by using a mixture of pomegranate seed oil and one of the other oils. The NLCs based on pomegranate seed oil combined with wheat germ oil have shown the best entrapment efficiency (70%) and photoprotection (SPF of 5.1 and a UVAPF of 9.5). All vegetable oils showed a good antioxidant activity, which was improved by their incorporation into NLCs. The results have shown that vegetable oils and especially their combinations can be used as renewable raw materials in designing effective and eco-friendly photoprotective nanostructured formulations.

The work aims to simulate in vitro the effects caused by oxidation of five hydroxyflavones (HF) (some typical models of flavonols), (3-HF, 6-HF, 7-HF, 3,6-diHF and 3,7-diHF) on silver nanoparticles (SNPs) using the chemiluminescent system luminol–hydrogen peroxide, in phosphate buffer, pH 7.4. The contribution of bovine and human serum albumins to the antioxidant activity of the mentioned flavones, and the effect on the SNPs support, in the chemiluminescent system luminol–hydrogen peroxide, has been also investigated. The results are discussed with relevance to the oxidative stress process.

This paper presents the spectral and electrochemical properties correlated to antioxidant character attributed to anthocyans: Pelargonidin-3-O-Glucoside, Cyanidin-3-O-Glucoside, Delphinidin-3-O-Glucoside, Peonidin-3-O-Glucoside, Malvidin-3-O-Glucoside. The Anthocyans were obtained and purified from natural selective hydroalcoholic extracts using HPLC chromatography. A series of determinations through the chemical voltammetry method were performed in view of identifying the anthocyanins’ oxidation and reduction potentials. These determinations were performed in electrochemical environments with different polarities and pH, in N, N-Dimethylformamide–Ethanol-Hydrochloric acid–Water systems. The results obtained offered data regarding the stability of anthocyans in the respective media. For Pelargonidin-3-O-Glucoside we performed detailed UV-VIS spectro-electrochemical measurements, using an optically transparent thin layer electrochemical cell. The results of these determinations offered information regardin...

The vegetable oils and extracts known for their beneficial effects should be identified and used in various forms for the development of new healthy products. This study was designed to provide further investigation on new nanocarriers made with hempseed oil or a blend of amaranth and hempseed oils, for a concomitant encapsulation and release of the carotenoids enriched plant extract. The size of plant extract loaded lipid nanocarriers ranging between 109 and 130 nm was found to be less influenced by the different ratios of hempseed and amaranth oils. For all of the synthesized nanocarriers, zeta potential values were negative (−33.4 ÷ −38.1 mV). The scanning calorimetry study has shown that lipid nanocarriers have favorable lattice defects for plant extract encapsulation. Entrapment efficiency results revealed an increase of carotenoids entrapment from 57.6 to 83.5% as the amaranth oil percent has been increased. High ability to scavenge the free oxygenated radicals was distinguished for all free and loaded nanocarriers. The level of antioxidant activity increase was proportional to the extent of vegetable oil and was ranging between 93.4 and 98.1%. The nanocarriers made with amaranth and hempseed oils have shown a more sustained release over time than those prepared with hempseed oil only in association with solid lipids. Practical applications: The applicability of lipophilic plant extracts enriched in bioactive compounds encounters serious problems in the food and pharmaceutical sector due to poor bioavailability. Using the concept of exploiting natural resources in combination with soft nanotechnology, valuable bioactive vegetable mixtures could be formulated into solid colloidal nanoparticles. The bioavailability and the therapeutic benefit of hempseed and amaranth oils in association with lipophilic plant extract enriched in carotenoids are increased by incorporation into the same nanostructured formulation. These formulations result in unique precursors of health products, particularly for nutraceutical industry. The lipid nanocarriers based on natural compounds offer potential applications as natural, low cost and innovative delivery systems to improve quality and extend shelf-life of food products. The developed vegetable based lipid nanocarriers offer advantages of a minimum carrier cytotoxicity, good storage stability, synergistic effects, antioxidant and sustained release, easy to scale up production. Lipid nanocarriers made with hempseed and amaranth oils and loaded with carotenoids extract from marigold plant. Influence of vegetable oils on in vitro antioxidant activity of developed lipid nanocarriers.

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.

Dye photodegradation of fullerene-modified silica materials has been investigated for ecological purposes. The highly efficient photodegradation process for the removal of 45% and 90% methylene blue dye under VIS and UVC light irradiation, respectively has proved the potential photo-degradative properties of these fullerene-modified silica materials. The key parameters that control photodegradation are quite high specific surface area (395 m 2 /g) of silica support, very low content of C 60 (0.04%) and the size effect promoted by homogeneous dispersion of C 60 nanoclusters (10 nm) in SiO 2 support. The enhancement of photodegradation efficiency is interpreted in terms of band gap energy and zeta potential values of the nanostructures under study.

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.

Natural, purely biological deoxyribonucleic acid (DNA)–green tea extract (GTE) complexes at different concentrations were prepared and characterized for their spectroscopic, fluorescent, linear and nonlinear optical properties. The complexes can be processed into good optical quality thin films by solution casting. They fluoresce when excited in UV absorption band, with a significantly larger quantum yield for the DNA–GTE complex than for a pure GTE solution. The thin film refractive indices were determined by Fabry–Perot (FP) interference patterns. The third-order nonlinear optical (NLO) properties of thin films were determined by the optical third-harmonic generation technique at 1064.2 nm fundamental wavelength. The phase of THG susceptibility was determined from the concentration variation of THG susceptibility. It reveals presence of a two-photon resonance with a band lying in the optical gap.

The coencapsulation of two UV filters, butyl-methoxydibenzoylmethane (BMDBM) and octocrylene (OCT), into lipid nanocarriers was explored to develop stable cosmetic formulations with broad-spectrum photoprotection and slow release properties. Different types of nanocarriers in various concentrations of the two UV filters were tested to find the combination with the best absorption and release properties. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) have been the two types of lipid nanocarriers used. The NLCs were based on either medium chain triglycerides (MCT) or squalene (Sq). The following physicochemical properties of the nanocarriers have been evaluated: particle size, morphology, zeta potential (ZP), entrapment efficiency, loading capacity, and thermal behavior. The nanocarriers have been formulated into creams containing low amounts of UV filters (2.5% BMDBM and 1% OCT). The best photoprotection results were obtained with the cream based on NLCs prepared with MCT, having a sun protection factor (SPF) of 17.2 and an erythemal UVA protection factor (EUVA-PF) of 50.8. The photostability of the encapsulated BMDBM filter was confirmed by subjecting the nanocarriers-based creams to in vitro irradiation. The prolonged UV-protection efficacy was coupled with a slow in vitro release of the synthetic UV filters, which followed the Higuchi release model.

The objective of this investigation was to develop solid lipid nanoparticles (SLNs) of umbelliferone by means of a high shear homogenization technique and to evaluate the efficiency of SLN systems in preserving and enhancing antioxidant activity of the flavonoid active component. The aqueous SLN dispersions combine two structural types of lipid compounds and different types of emulsifiers including a mixture of monoalkyl polyoxyethylene sorbitan with a block copolymer and lecithin. The assessment of umbelliferone stability in aqueous SLN dispersions, the size distribution of lipid nanoparticles loaded with umbelliferone (by DLS technique), as well as the structural changes (FT-IR spectroscopy and differential scanning calorimetry) of these lipid nanomatrices have been investigated. Moreover, the influence of umbelliferone concentration onto entrapment efficiency and antioxidant properties were clearly evidenced on four kinds of lipid nanoparticles. The umbelliferone-loaded SLN prepared with polyethylene g...

Among the waste generated in leather processing, proteic and lipidic compounds are particularly dominant. Enzymes, like proteases and lipases, have an important role in biodegradation of collagen, keratin and fats in leather waste. Present investigation deals with isolation, selection and characterization of proteolytic and lipolytic microorganisms in order to perform biodegradation of waste from leather industry. The inoculum of microorganisms was sampled from old waste storage dump leather. The proteolytic microorganisms were isolated using screening method in presence of casein and gelatin substrate type, respectively. The microorganisms that secrete the lipolytic enzymes were isolated using medium that contained the Tween 80. These microorganisms identified by microscopic analysis can be used for improvement of waste leather biodegradation process.

Photochemical and thermal stability of thin films formed from selected optically responsive chromophores embedded in deoxyribonucleic acid (DNA), Collagen and in the complex formed by DNA biopolymer and the surfactant hexadecyl ammonium (CTMA) matrix was studied by UV-VIS and compared with that observed when using some synthetic polymers (polymethylmetacrylate – PMMA, polycarbonate – PC). In particular the influence of external stimuli, such as heating and UV light on the chemical degradation process was investigated.

NiO–silica based materials have been synthesized by microemulsion assisted sol–gel procedure. The versatility of these soft nanotechnology techniques has been exploited in order to obtain different types of nanostructures, such as NiO nanoparticles, NiO silica coated nanoparticles and NiO embedded in silica matrix. These materials have been characterized by adequate structural and morphology techniques: DLS, HR-TEM/SAED, BET, AFM. Optical and semiconducting properties (band-gap values) of the synthesized materials have been quantified by means of VIS–NIR diffuse reflectance spectra, thus demonstrating their applicative potential in various electron transfer phenomena such as photocatalysis, electrochromic thin films, solid oxide fuel cells.

Hybrid sol-gel films containing Rosemary extract nanoclusters embedded into hybrid silica network have been successfully synthesized using the sol-gel procedure by exploiting the template route, in association with an adequate spin-coating method. Formation of film precursor sols and effect of selected amounts of octyl trimethoxysilane and ethyl oleate succinic anhydride into the starting acid sols on the sol-gel product size have been evaluated by dynamic light scattering technique. The spectral characteristics of hybrid organic–inorganic films have shown that the multiple functional groups from Rosemary extract associated with residual Si–OH groups can cause the increase in the degree of physical interaction. The effect of hybrid sols meaning the silica precursors molar ratio and template concentration on the fluorescence of hybrid films has been also investigated. The fluorescence properties of synthesized films were found to be dependent on template and natural extract concentration. A higher amount of template resulted in doubling the fluorescence intensity in the 400–480 nm domain. The microstructural characteristics of the hybrid films revealed by atomic force microscopy have shown a homogeneous surface morphology with cluster-like structure. Hybrid silica films exhibit a periodic structure with cluster size less than 150 nm.

In the present paper a non-surfactant templating route has been employed to prepare new fluorescence nanostructured materials, by combining some natural organic molecules present in vegetal extracts with three-dimensional silica and hybrid silica-silsesquioxane networks. The results obtained clearly indicated that organic chromophores like flavonoid compounds from two extracts with bio-active principles (orange peel extract and ornamental bush extract) can be efficiently immobilised in the host silica and hybrid matrices, using D-fructose as template. The confirmation of immobilization process was demonstrated by extensive characterization of final materials, achieved based on spectroscopy technique, fluorescence intensity measurements and transmission electron microscopy.

The sol–gel encapsulation of labile substances with specific properties and recognition functions within robust polymer matrices remains a challenging task, despite the considerable research that has been focused on this field. Numerous studies have been reported in the field of sol–gel processes regarding different physical and chemical packing of sensitive biomolecules encapsulated in silica matrix. In this paper the classical sol–gel synthesis has been used under mild conditions in order to minimize denaturizing effects on encapsulated active vegetable extracts from flavones class. The silica templated matrix was obtained by using two types of surfactants with different alkyl chain (didodecyldimethyl-ammonium bromide and trioctadecylmetilammonium bromide) as structure-directing agents for the silicon oxide framework. An organic precursor of silicic acid (triethoxymethylsilane) has been used and it was processed by competitive hydrolysis and polycondensation reactions under controlled directions assured by the presence of oriented template. Silica materials thus obtained are used for encapsulation of two flavonoid samples containing as active principles two sources: rutin and a vegetable extract from Begonia plant. The synthesis of encapsulated nanocompounds has been achieved taking into consideration the specific interaction between the colloidal gel precursors and molecular structures of selected biomolecules. The main objective was to improve the encapsulation conditions for specific biomolecules, searching for the highest stability and functionality without loosing the quality of the flavonoid properties, particularly optical properties like fluorescence. The structural properties of the encapsulated samples have been studied by FT-IR and UV–VIS spectroscopy, thermal analysis and SEM/EDX analysis. The fluorescence experiments showed that, in the case of all four encapsulated samples, the fluorescence spectra manifest a significant increase in intensity signals, with more than 10 times for individual flavonoid and 50 times for Begonia extract. This behaviour are mainly assigned to the physical interaction of flavonoid molecules with the residual hydroxyl groups of silica, excellent synergistic properties of silica and the favourable conformation arrangement of organic molecules inside the silica network. The size distribution of synthesised polymeric silica materials have been investigated by dynamic light scattering (DLS) and optical microscopy.

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.

Sol–gel chemistry can be easily modified to the changing needs of society to produce fine-tuned sol–gel nanostructured materials for relevant applications. In this context, there is an increasing need for natural and versatile raw materials as well as biocompatible compounds that could be extensively used as biomarkers for bioimaging in diagnosis or therapy. Silica-based materials are widely used in the field of biomedicine due to their chemical inertness and biocompatibility. In the present paper, orange peel extract was immobilized inside inorganic silica and hybrid silica-silsesquioxane polymeric networks. Silica and organo-modified silica matrices were synthesized through a templated sol–gel route of TEOS and an organosilsesquioxane (octaisobutyltetracyclo[7.3.3.15,11] octasiloxane-endo-3,7-diol), with D-glucose as template, and for comparison a non-ionic surfactant (tetraethylene glycol mono-hexadecyl ether) was also used. The bioactive properties of the molecules from orange peel extract were preserved after immobilization in both silica and silica-silsesquioxane networks. Moreover, the fluorescence properties were amplified by 10–20 times more than the native orange peel extract. The structural properties of the final materials have been studied by FT-IR, UV–Vis-NIR, and fluorescence spectroscopy. Dynamic light scattering measurements and transmission electron microscopy were used to estimate the size and morphology of the hybrid materials with orange peel extract immobilized in silica networks. Copyright © 2009 John Wiley & Sons, Ltd.

The aim of paper is focused on development of novel alternative solutions in order to realise a combination of sensitive molecules with rigid support materials. In this context, a new class of silica precursors based on bridge bonded silsesquioxane organised into periodic mesoporous architecture is suitable for this purpose. A silsesquioxane incompletely condensed (dimethylvinylsilyloxy)-heptacyclo-pentyltricycloheptasiloxanediol) has been selected for sol–gel bioentrapment of retinyl palmitate, in an approach based on high biocompatibility and mild sol–gel encapsulation conditions which enables the reproducible and efficient confinement of retinyl palmitate inside silica. For entrapping of retinyl palmitate within cage structure a templating agent was used, n-dodecyl-β-D-maltoside. The process used for retinyl palmitate encapsulation in silsesquioxane matrix consisted in two main steps: the first step was the synthesis of glucosidal template silica materials, and the second was the encapsulation ...

A biomonitoring method has been developed for determination of both inorganic and organic Hg in fresh and canned fish and also in blood based on ICP–MS coupled with high performance liquid chromatography (HPLC). In this way, the species of Hg which are present in organic samples like fish food can be determined. The speciation was developed to determine the methyl mercury content and, concomitantly, the atomic absorption spectroscopy method was used to determine the total mercury content in fish food. The present study reports the concentrations of total mercury and its speciation in fresh and canned fish food and these amounts have been found to be significantly higher in predatory species of fish while the most abundant species was methyl mercury. Moreover, some correlations have been performed between biomonitoring results and determination of mercury compounds in fish samples purchased from a local market in order to evaluate the speciation of Hg in fish food.

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.

Human exposure to heavy metals requires special surveillance measures on these elements in human body in order to detect a relation between heavy metal exposure and adverse health effects. The aim of this paper is focused on biomonitoring contamination with heavy metals in fish foodstuffs and in blood, and corroboration of contaminant levels with immunotoxicological effects on target groups of consumers. The final goal is to establish some recommendations on human diet with fish foodstuff in order to assure a significant improvement in food safety.

Economical development in the Arges district, in the recent years, presents some aspects regarding the compliance with noise environmental regulations. The noise and its impact on human health is one of the most important objectives of the health assurance policy. In this paper a comparative study of urban noise in the principal cities of the Arges district is performed. The data monitoring of noise polution were carried out by using of specific standard methods with a Sonometer Delta 2010. There are correlations between the activities highlighted monitoring pollution with noise and economical and social activities in the area. Similar areas registration of noise were selected for the measure of sound equivalent level, instantaneous peak level or maximum peak level: in nearby schools, hospitals, roads and parks. These results are been presented by comparing parameters of noise witch were determinated in the similar conditions, but in different periods of time.

A number of 46 out of a total of more than 200 recent patents in soft nanotechnology referring to applications of nanoemulsions for pharmaceutical and cosmetical formulations has been selected and reviewed. As key factors to maximize the efficiency of bioactive principles embedded within colloidal drug delivery systems are the nature and ratio of hydrophilic/lipophilic components, of surfactants/cosurfactants as emulsifiers, their mutual solubility and biocompatibility, the size and polydispersity of nanoparticles. The antioxidant and immunostimulative actions are discussed in relation to the specific therapeutic effects of galenical compositions used for preventing and/or treating various diseases.

Semiconductor nanoparticles have attracted much interest during the past decade due to their unique size-dependent chemical and physical properties. These properties emerge from the high surface-to-volume ratio present in nanoparticles. CdS nanoparticles have potential applications as optoelectronic devices, lasers, photocatalysts, electrochemical cells, fluorescent labelling of cell organelles. A series of cadmium sulphide (CdS) nanocrystalline were synthesized by precipitation from a mixture of aqueous solutions of various cadmium salts and sodium thiosulphate at room temperature without adding any surface-termination agent. Their crystal structure and particle size were determined by X-ray diffraction. The fluorescence of CdS nanocrystalline and UV-Vis absorption spectra were also recorded. The relationship between the synthesis conditions and spectroscopic properties was studied. Several factors affect the absorbance and fluorescence spectra, including the cadmium source and Cd:S molar ratio. It has f...