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In this study, hybrid bio-nanoporous peptides loaded onto poly(N-isopropylacrylamide-co-butylacrylate) (pNIPAM-co-BA) coatings were designed and obtained via matrix-assisted pulsed laser evaporation (MAPLE) technique. The incorporation of cationic peptides magainin (MG) and melittin (Mel) and their combination was tailored to target synergistic anticancer and antibacterial activities with low toxicity on normal mammalian cells. Atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy as well as contact angle and surface energy measurements revealed the successful and functional incorporation of both the peptides within porous polymeric nanolayers as well as surface modifications (i.e. variation in the pore size diameter, surface roughness, and wettability) after Mel, MG or Mel-MG incorporation compared to pNIPAM-co-BA. In vitro testing revealed the impairment of biofilm formation on all the hybrid coatings while testing with S. aureus, E. coli and P. aeruginosa. Moreover, MG was shown to modulate the effect of Mel in the combined Mel-MG extract formulation released via pNIPAM-platforms, thus significantly reducing cancer cell proliferation through apoptosis/necrosis as revealed by flow cytometry analysis performed in vitro on HEK293T, A375, B16F1 and B16F10 cells. To the best of our knowledge, Mel-MG combination entrapped in the pNIPAM-co-BA copolymer has not yet been reported as a new promising candidate with anticancer and antibacterial properties for improved utility in the biomedical field. Mel-MG incorporation compared to pNIPAM-co-BA in in vitro testing revealed the impairment of biofilm formation in all the hybrid formulations.
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The nature of the E-O chemical bond (E = C, Si, Ge, Sn) is investigated in a wide range of model derivatives, such as oxonium cations, hydrogenated/methylated/fluorinated/chlorinated ethers and acyclic oligomers incorporating the E-O-E moiety. By means of density functional theory (DFT) calculations and natural bond orbital (NBO) techniques, we propose a bonding mechanism that explains the structural contrast between the organic and the inorganic counterparts of all these derivatives: the interplay between stabilizing interactions like LP(O)âσ*(E-X) hyperconjugations and LP(O)âd(E) donations with LP(O)â¯σ(E-X) vicinal Pauli repulsions (X = H, C, O, F, Cl) dictates the equilibrium structures in terms of E-O-E angles and E-O bond lengths. In addition, the present work represents the first study of oxonium ions that describes the structural discrepancies among organic derivatives and their heavier analogues. Another novel outcome for ethers and oligomers is that the two non-equivalent lone pair electrons (LPs) at the oxygen atoms impact in different manners the geometries of such derivatives, i.e. the s/p LP is correlated with the bending behaviour of the E-O-E units, while the pure p LP mainly dictates the short E-O bond distances of inorganic derivatives. Lastly, we evaluate the impact of the number of electronegative substituents, e.g. F, Cl or OEH3 groups, on the bond patterns developed for hydrogenated or methylated ethers.
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In this study, the effect of common non-steroidal anti-inflammatory drugs on Lycopersicon esculentum rhizosphere microbiota was monitored. The experiments were performed with artificially contaminated soil with ibuprofen (0.5 mg·kg-1), ketoprofen (0.2 mg·kg-1) and diclofenac (0.7 mg·kg-1). The results evidenced that the rhizosphere microbiota abundance decreased especially under exposure to diclofenac (187-201 nmol·g-1 dry weight soil) and ibuprofen (166-183 nmol·g-1 dry weight soil) if compared with control (185-240 nmol·g-1 dry weight soil), while the fungal/bacteria ratio changed significantly with exposure to diclofenac (<27%) and ketoprofen (<18%). Compared with control samples, the average amount of the ratio of Gram-negative/Gram-positive bacteria was higher in rhizosphere soil contaminated with ibuprofen (>25%) and lower in the case of diclofenac (<46%) contamination. Carbon source consumption increased with the time of assay in case of the control samples (23%) and those contaminated with diclofenac (8%). This suggests that rhizosphere microbiota under contamination with diclofenac consume a higher amount of carbon, but they do not consume a larger variety of its sources. In the case of contamination with ibuprofen and ketoprofen, the consumption of carbon source presents a decreasing tendency after day 30 of the assay. Rhizosphere microbiota emitting volatile organic compounds were also monitored. Volatile compounds belonging to alcohol, aromatic compounds, ketone, terpene, organic acids, aldehyde, sulphur compounds, esters, alkane, nitrogen compounds, alkene and furans were detected in rhizosphere soil samples. Among these, terpene, ketone, alcohol, aromatic compounds, organic acids and alkane were the most abundant compound classes (>75%), but their percentage changed with exposure to diclofenac, ketoprofen and ibuprofen. Such changes in abundance, structure and the metabolic activity of Lycopersicon esculentum rhizosphere microbiota under exposure to common non-steroidal anti-inflammatory drugs suggest that there is a probability to also change the ecosystem services provided by rhizosphere microbiota.
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In this work, thin films of lamellar clays were deposited by laser techniques (matrix assisted pulsed laser evaporation (MAPLE) and pulsed laser deposition (PLD)). The focus of this paper is the optimization of deposition parameters for the production of highly oriented crystalline films. The films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). Contact angle measurements were employed to identify the wetting properties of the deposited thin films. Hydrophobic to superhydrophilic films can be prepared by using different deposition techniques and deposition parameters. MAPLE led to superhydrophilic films with contact angles in the range 4°-8°, depending on the microstructure and surface roughness at micro and nano scale. The 1064 nm PLD had a high deposition rate and produced a textured film while at λ = 193 nm an extremely thin and amorphous layer was depicted. Oriented kaolinite films were obtained by MAPLE even at 5 wt.% kaolinite in the target.
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In the last decades, optimizing implant properties in terms of materials and biointerface characteristics represents one of the main quests in biomedical research. Modifying and engineering polyvinylidene fluoride (PVDF) as scaffolds becomes more and more attractive to multiples areas of bio-applications (e.g., bone or cochlear implants). Nevertheless, the acceptance of an implant is affected by its inflammatory potency caused by surface-induced modification. Therefore, in this work, three types of nano-micro squared wells like PVDF structures (i.e., reversed pyramidal shape with depths from 0.8 to 2.5 microns) were obtained by replication, and the influence of their characteristics on the inflammatory response of human macrophages was investigated in vitro. FTIR and X-ray photoelectron spectroscopy analysis confirmed the maintaining chemical structures of the replicated surfaces, while the topographical surface characteristics were evaluated by AFM and SEM analysis. Contact angle and surface energy analysis indicated a modification from superhydrophobicity of casted materials to moderate hydrophobicity based on the structure's depth change. The effects induced by PVDF casted and micron-sized reversed pyramidal replicas on macrophages behavior were evaluated in normal and inflammatory conditions (lipopolysaccharide treatment) using colorimetric, microscopy, and ELISA methods. Our results demonstrate that the depth of the microstructured surface affects the activity of macrophages and that the modification of topography could influence both the hydrophobicity of the surface and the inflammatory response.
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We report here the synthesis and structural characterization of novel cationic (phenothiazinyl)vinyl-pyridinium (PVP) dyes, together with optical (absorption/emission) properties and their potential applicability as fluorescent labels. Convective heating, ultrasound irradiation and mechanochemical synthesis were considered as alternative synthetic methodologies proficient for overcoming drawbacks such as long reaction time, nonsatisfactory yields or solvent requirements in the synthesis of novel dye (E)-1-(3-chloropropyl)-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium bromide 3d and its N-alkyl-2-methylpyridinium precursor 1c. The trans geometry of the newly synthesized (E)-4-(2-(7-bromo-10-ethyl-10H-phenothiazin-3-yl)vinyl)-1-methylpyridin-1-ium iodide 3b and (E)-1-methyl-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium tetrafluoroborate 3a' was confirmed by single crystal X-ray diffraction. A negative solvatochromism of the dyes in polar solvents was highlighted by UV-Vis spectroscopy and explanatory insights were supported by molecular modeling which suggested a better stabilization of the lowest unoccupied molecular orbitals (LUMO). The photostability of the dye 3b was investigated by irradiation at 365 nm in different solvents, while the steady-state and time-resolved fluorescence properties of dye 3b and 3a' in solid state were evaluated under one-photon excitation at 485 nm. The in vitro cytotoxicity of the new PVP dyes on B16-F10 melanoma cells was evaluated by WST-1 assay, while their intracellular localization was assessed by epi-fluorescence conventional microscopy imaging as well as one- and two-photon excited confocal fluorescence lifetime imaging microscopy (FLIM). PVP dyes displayed low cytotoxicity, good internalization inside melanoma cells and intense fluorescence emission inside the B16-F10 murine melanoma cells, making them suitable staining agents for imaging applications.
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Corantes Fluorescentes/química , Compostos de Piridínio/química , Coloração e Rotulagem/métodos , Animais , Corantes Fluorescentes/síntese química , Camundongos , Microscopia de Fluorescência , Fenotiazinas/química , Fótons , Compostos de Piridínio/síntese química , Solventes/química , Espectrometria de Fluorescência/métodosRESUMO
Osseous implantology's material requirements include a lack of potential for inducing allergic disorders and providing both functional and esthetic features for the patient's benefit. Despite being bioinert, Zirconia ceramics have become a candidate of interest to be used as an alternative to titanium dental and cochlear bone-anchored hearing aid (BAHA) implants, implying the need for endowing the surface with biologically instructive properties by changing basic parameters such as surface texture. Within this context, we propose anisotropic and isotropic patterns (linear microgroove arrays, and superimposed crossline microgroove arrays, respectively) textured in zirconia substrates, as bioinstructive interfaces to guide the cytoskeletal organization of human mesenchymal stem cells (hMSCs). The designed textured micro-nano interfaces with either steep ridges and microgratings or curved edges, and nanoroughened walls obtained by direct femtosecond laser texturing are used to evaluate the hMSC response parameters and osteogenic differentiation to each topography. Our results show parallel micro line anisotropic surfaces are able to guide cell growth only for the steep surfaces, while the curved ones reduce the initial response and show the lowest osteogenic response. An improved osteogenic phenotype of hMSCs is obtained when grown onto isotropic grid/pillar-like patterns, showing an improved cell coverage and Ca/P ratio, with direct implications for BAHA prosthetic development, or other future applications in regenerating bone defects.
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This work describes an efficient, simple, and ecofriendly sonochemical procedure for the preparation of new α-(arylamino)acetonitrile derivatives C-substituted with phenothiazine or ferrocene units. The synthetic protocol is based on the Strecker reaction of a (hetero)aryl aldimine substrate with trimethylsilyl cyanide (TMSCN) in poly(ethylene glycol) (PEG) solution. The advantages of the sonochemical versus the conventional α-(arylamino)acetonitrile synthesis are the significantly shorter reaction time (30 min instead of 72 hours), the higher purity and the easier separation of the product that precipitated from the reaction mixture in crystalline form as depicted by scanning electron microscopy (SEM) analysis. The single crystal X-ray diffraction analysis disclosed the arrangement of the α-(arylamino)acetonitrile molecules in the aggregated crystalline state as a racemic mixture. The mutagenic/antimutagenic potential for three representative derivatives containing phenothiazinyl, ferrocenyl, and phenyl units, respectively, was evaluated by the Ames Salmonella/microsome test using S. typhimurium TA98 and TA100 strains with and without metabolic activation. The preliminary screening results pointed out that the C-(hetero)aryl-α-(arylamino)acetonitrile derivatives can be considered genotoxically safe and possibly antimutagenic.
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We report here the synthetic procedure applied for the preparation of new AB3-type and trans-A2B2 type meso-halogenophenothiazinyl-phenyl-porphyrin derivatives, their metal core complexation and their peripheral modification using Suzuki-Miyaura cross coupling reactions with various (hetero)aryl (phenothiazinyl, 7-formyl-phenothiazinyl, (9-carbazolyl)-phenyl and 4-formyl-phenyl, phenyl) boronic acid derivatives. The meso-phenothiazinyl-phenyl-porphyrin (MPP) dyes family was thus extended by a series of novel phenothiazine-bridged porphyrin-(hetero)aryl dyads characterized by UV-Vis absorption/emission properties typical to the porphyrin chromophore, slightly modulated by increasing the size of peripheral substituents. Three phenothiazine-bridged porphyrin-heteroaryl dyads with fluorescence emission above 655 nm were selected as fluorophores in red spectral region for applications in cellular staining of human ovarian tumors. In vitro experiments of cell metabolic activity displayed a moderate toxicity on human ovarian tumor cell lines (OVCAR-3, cisplatin-sensitive A2780 and cisplatin-resistant A2780cis respectively). Visualization of the stained living cells was performed both by fluorescence microscopy imaging and by fluorescence lifetime imaging under two photon excitation (TPE-FLIM), confirming their cellular uptake and the capability of staining the cell nucleus.
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Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Fenotiazinas/química , Porfirinas/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Microscopia de FluorescênciaRESUMO
Recent advancements in biomedicine have focused on designing novel and stable interfaces that can drive a specific cellular response toward the requirements of medical devices or implants. Among these, in recent years, electroactive polymers (i.e., polyvinylidene fluoride or PVDF) have caught the attention within the biomedical applications sector, due to their insolubility, stability in biological media, in vitro and in vivo non-toxicity, or even piezoelectric properties. However, the main disadvantage of PVDF-based bio-interfaces is related to the absence of the functional groups on the fluoropolymer and their hydrophobic character leading to a deficiency of cell adhesion and proliferation. This work was aimed at obtaining hydrophilic functional PVDF polymer coatings by using, for the first time, the one-step, matrix-assisted pulsed evaporation (MAPLE) method, testing the need of a post-deposition thermal treatment and analyzing their preliminary capacity to support MC3T3-E1 pre-osteoblast cell survival. As osteoblast cells are known to prefer rough surfaces, MAPLE deposition parameters were studied for obtaining coatings with roughness of tens to hundreds of nm, while maintaining the chemical properties similar to those of the pristine material. The in vitro studies indicated that all surfaces supported the survival of viable osteoblasts with active metabolisms, similar to the "control" sample, with no major differences regarding the thermally treated materials; this eliminates the need to use a secondary step for obtaining hydrophilic PVDF coatings. The physical-chemical characteristics of the thin films, along with the in vitro analyses, suggest that MAPLE is an adequate technique for fabricating PVDF thin films for further bio-applications.
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Técnicas de Química Sintética , Osteoblastos/efeitos dos fármacos , Polivinil/farmacologia , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dimetil Sulfóxido/farmacologia , Calefação , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Polivinil/química , Propriedades de SuperfícieRESUMO
The molecular frame of the reported series of new polyheterocyclic compounds was intended to combine the potent phenothiazine and benzothiazole pharmacophoric units. The synthetic strategy applied was based on oxidative cyclization of N-(phenothiazin-3-yl)-thioamides and it was validated by the preparation of new 2-alkyl- and 2-aryl-thiazolo[5,4-b]phenothiazine derivatives. Optical properties of the series were experimentally emphasized by UV-Vis absorption/emission spectroscopy and structural features were theoretically modelled using density functional theory (DFT). In vitro activity as antileukemic agents of thiazolo[5,4-b]phenothiazine and N-(phenothiazine-3-yl)-thioamides were comparatively evaluated using cultivated HL-60 human promyelocytic and THP-1 human monocytic leukaemia cell lines. Some representatives proved selectivity against tumour cell lines, cytotoxicity, apoptosis induction, and cellular metabolism impairment capacity. 2-Naphthyl-thiazolo[5,4-b]phenothiazine was identified as the most effective of the series by displaying against THP-1 cell lines a cytotoxicity close to cytarabine antineoplastic agent.
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Antineoplásicos/química , Antineoplásicos/farmacologia , Fenotiazinas/química , Fenotiazinas/farmacologia , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Fenotiazinas/síntese química , Análise Espectral , Relação Estrutura-AtividadeRESUMO
The synthesis and characterization of an E2 CE2 bis-sulfonyl aryl pincer ligand and its efficiency for the stabilization of compounds containing low-valent Groupâ 14 elements (Ge and Sn) are reported. Complexation reaction of these metallylenes with iron or tungsten complexes resulted in the modulation of the oxygen atoms of the sulfonyl groups implicated in the stabilization of the Groupâ 14 elements, demonstrating the original adjustable character of the bis-sulfonyl O2 S-C-SO2 aryl pincer.
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The aim of this study is to investigate and develop a phytoremediation method for the removal of two triphenylmethane dyes (crystal violet and malachite green) using an aquatic plant, Lemna minor. The effects of operational parameters such as aquatic plant quantity, initial dye concentration, initial pH of the solutions and temperature of the medium were studied in order to determine the optimum phytoremediation conditions. The plant's photosynthetic pigments were determined quantitatively in order to detect the plant's response to abiotic stress. During the phytoremediation experiments the parallel sub-processes (phytosorption, phytoextraction, phytodegradation) were observed and analysed. The mechanisms of phytoremediation were studied using Fourier transformation infrared spectroscopy, ultraviolet-visible spectroscopy, thin layer chromatography and Energy-dispersive X-ray spectroscopy. Results show that the plant tolerated high concentrations (300 mg/L) of dyes, and was able to remove from the environment and accumulate in its cells the dyes up to a significant percentage (crystal violet was removed by about 80% and malachite green by 90%).
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Araceae/metabolismo , Biodegradação Ambiental , Corantes/isolamento & purificação , Violeta Genciana/isolamento & purificação , Corantes de Rosanilina/isolamento & purificação , Concentração de Íons de Hidrogênio , SoluçõesRESUMO
Starting from heterotopic multidentate ligand 2,2'-(1,2-phenylenedisulfanediyl)diacetic acid, (RS,RS,RS,RS/SS,SS,SS,SS)-[Ag{1,2-C6H4(SCH2COOH)2-κ2S,S'}2]BF4 (1) was prepared and further used as a building block for the synthesis of heterobimetallic Ag-Cd coordination polymer [Ag2Cd2{1,2-(OOCCH2S)2C6H4}3 (H2O)3·5H2O]n (2). Both complexes were characterized by X-ray structure analysis and conventional spectroscopic techniques.
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Cádmio/química , Polímeros/química , Compostos de Prata/química , Prata/química , Ligantes , Estrutura Molecular , Raios XRESUMO
OBJECTIVES: The objective of this study was to study the feasibility of a recently developed instrument, LPZ-International, which assesses care problems in health care, and to describe the prevalence of care problems in Romanian health care institutions. Large differences exist in care services in Europe. Data on quality of care are absent or incomplete in Central-Eastern European countries. These countries, including Romania, have faced dramatic socioeconomic changes, which led to negative changes in quality of care. DESIGN: Cross-sectional study. SETTING: Hospital wards, mental care institutions, and nursing homes. PARTICIPANTS: Nine health care institutions and admitted 394 patients. MEASURES: LPZ-International was introduced in 9 health care institutions in Romania. Assessed care problems included pressure ulcers, urinary and fecal incontinence, malnutrition, falls, and physical restraints. The data were collected between November 2013 and March 2014. Two health care professionals completed the questionnaire by hand at the patient's site. RESULTS: Six of the 9 health care institutions and 90% of the patients participated, which indicates the feasibility of LPZ-International, as did the completeness of the questionnaire. The data showed a high consistency and only a few were missing. The most frequent care problem was urinary and fecal incontinence, especially in the nursing home. Pressure ulcers and malnutrition were less frequent care problems in Romanian patients. Physical restraints were frequently applied in the nursing home and geriatrics and oncology wards. CONCLUSIONS: LPZ-International is a feasible instrument to assess care problems. The differences between wards and countries in the prevalence of care problems indicate differences in quality of care and the need for high-quality, comparative research.
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Acidentes por Quedas/estatística & dados numéricos , Incontinência Fecal/epidemiologia , Úlcera por Pressão/epidemiologia , Qualidade da Assistência à Saúde , Incontinência Urinária/epidemiologia , Acidentes por Quedas/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Estudos de Viabilidade , Incontinência Fecal/prevenção & controle , Feminino , Necessidades e Demandas de Serviços de Saúde , Hospitais , Hospitais Psiquiátricos , Humanos , Masculino , Casas de Saúde , Úlcera por Pressão/prevenção & controle , Prevalência , Romênia/epidemiologia , Inquéritos e Questionários , Incontinência Urinária/prevenção & controleRESUMO
New and known arylidene-hydrazinyl-thiazole derivatives have been synthesized by a convenient Hantzsch condensation. All compounds were evaluated for their in vitro cytotoxicity on two carcinoma cell lines, MDA-MB231 and HeLa. Significant antiproliferative activity for 2-(2-benzyliden-hydrazinyl)-4-methylthiazole on both MDA-MB-231 (IC50: 3.92 µg/mL) and HeLa (IC50: 11.4 µg/mL) cell lines, and for 2-[2-(4-methoxybenzylidene) hydrazinyl]-4-phenylthiazole on HeLa (IC50: 11.1 µg/mL) cell line is reported. Electrophoresis experiments showed no plasmid DNA (pTZ57R) cleavage in the presence of the investigated thiazoles.
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Hidrazinas/síntese química , Hidrazinas/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Hidrazinas/química , Concentração Inibidora 50 , Substâncias Intercalantes/farmacologia , Tiazóis/químicaRESUMO
In cancer therapy the platinum-based drugs are used frequently with a good clinical outcome, but besides unwanted side effects which occur, the tumour cells subjected to treatment are prone to develop tolerance or even multidrug resistance (MDR). Metal compounds with a central atom other than platinum are efficient in targeting the chemoresistant cells, therefore the biological outcome of two recently synthesized gallium phosphinoarylbisthiolato complexes was studied, having the formula [X][Ga{PPh(2-SC6H4)2-κ(3)S,S',P}{PPh(2-SC6H4)2-κ(2)S,S'}] where [X] is either the NEt3H (1) or PPh4 (2) cation. Compounds 1 and 2 display in vitro cytotoxicity against both platinum-sensitive and platinum-resistant cell lines (A2780 and A2780cis). Morphological and ultrastructural evidence points toward their capacity to impair tumour cells survival. This behaviour is based on malignant cells capacity to selectively intake gallium, and to bind to the cellular DNA. They are able to cause massive DNA damage in treated cancer cells, focusing on 7-methylguanine and 8-oxoguanine sites and oxidizing the pyrimidine bases; this leads to early apoptosis of a significant percent of treated cells. The intrinsic and extrinsic apoptotic pathways are influenced through the modulation of gene expression following the treatment with complexes 1 and 2, which accompanies the negative regulation of P-glycoprotein 1 (Pgp-1), an important cellular ABC-type transporter from the multidrug resistance (MDR) family. The studied Ga(III) compounds demonstrated the capacity to counteract the chemoresistance mechanisms in the tumours defiant to standard drug action. Compound 2 shows a good anticancer potential and it could represent an alternative to platinum-based drugs especially in the situation of standard treatment failure.
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Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Gálio/farmacologia , Neoplasias/tratamento farmacológico , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/química , Dano ao DNA/efeitos dos fármacos , Gálio/química , Humanos , Modelos Moleculares , Neoplasias/genética , Neoplasias/metabolismoRESUMO
Biosorption of cadmium ions from synthetic aqueous solution using popular Romanian fir tree sawdust (Abies Alba) as biosorbent, was investigated in this work. Prior to its utilization the considered biomass was washed, dried and sieved without further chemical treatments. The biosorbent was characterized using humidity, density and elemental analysis determinations and FTIR. FTIR analysis indicated that, on the biomass surface hydroxyl and carboxyl groups are presented. The effect of different biosorption parameters was studied. Higher biomass quantity, neutral pH, slightly elevated temperature and high cadmium ions concentration are all favouring the biosorption process. Equilibrium (Langmuir and Freundlich isotherm), kinetics and thermodynamics of the considered biosorption process were discussed in details. Equilibrium was best described by the Langmuir isotherm, while the kinetic of the process was best described by the pseudo-second-order model, suggesting monolayer coverage and a chemisorption process. Thermodynamic parameters showed that cadmium biosorption process on fir tree sawdust is an endothermic process.
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Abies/metabolismo , Biodegradação Ambiental , Cádmio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Biomassa , Cátions , Microscopia Eletrônica de Varredura , Modelos Teóricos , Espectroscopia de Infravermelho com Transformada de Fourier , TermodinâmicaRESUMO
New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based on spectroscopic data (FT-IR, ¹H-NMR), MS and elemental analysis. Selenazole derivatives were screened for their anti-proliferative effects against two leukemia cell lines (CCRF-CEM and HL60) and three carcinoma cell lines (MDA-MB231, HCT116 and U87MG).
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Azóis/química , Azóis/farmacologia , Micro-Ondas , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HCT116 , Células HL-60 , Humanos , Concentração Inibidora 50RESUMO
Heteropolytopic arsanylthiolato ligands 1-AsPh(2)-2-SHC(6)H(4) (AsSH), PhAs(2-SHC(6)H(4))(2) (AsS(2)H(2)), and As(2-SHC(6)H(4))(3) (AsS(3)H(3)) have been prepared by lithiation-electrophilic substitution procedures. The 2:1 reaction of AsSH with NiCl(2)·6H(2)O, Na(2)[PdCl(4)], and [PtI(2)(cod)] (cod = 1,5-cyclooctadiene) in the presence of NEt(3) afforded the square-planar complexes trans-[Ni{(AsS)-κ(2)S,As}(2)] (1), cis-[Pd{(AsS)-κ(2)S,As}(2)] (2), trans-[Pd{(AsS)-κ(2)S,As}(2)] (3), and cis-[Pt{(AsS)-κ(2)S,As}(2)] (4). In the cases of nickel and platinum, only one isomer was isolated. With palladium, initially the cis isomer 2 is formed and undergoes slow isomerization to the trans isomer 3 in solution. Small amounts of the trinuclear complex [{PtI(1-AsPh(2)-µ-2-S-C(6)H(4)-κ(2)S,As)}(3)] (5) are also formed besides the mononuclear platinum bis-chelate complex 4. Density functional theory calculations support a dissociative mechanism for the isomerization of the palladium(II) complexes.