Organic Solvents Of Different Polarity Research Articles

Control of the chickpea blight, Ascochyta rabiei, with the weed plant, Withania somnifera

BackgroundAscochyta blight caused by a fungal pathogen, Ascochyta rabiei, is a serious disease of chickpea in most chickpea growing areas of the world. The disease can be controlled by fungicides to reduce the environmental pollution.Main bodyThis study reports the control of Ascochyta blight by using extracts and dry biomass of a weed plant, Withania somnifera (Family Solanaceae). In a laboratory bioassay, a 0.2% concentration of methanolic leaf extract of W. somnifera significantly inhibited the pathogenic fungal growth. Methanolic leaf extract was fractionated with 4 organic solvents of different polarities namely n-hexane, chloroform, ethyl acetate, and n-butanol. The effect of different concentrations (3.125, 6.25, 12.5, 25, 50, 100, 200 mg ml−1) of the 4 organic solvent fractions was assessed on in vitro growth of the pathogen. Among these, ethyl acetate and n-butanol fractions completely inhibited the fungal growth. Ethyl acetate fraction was further subjected to thin layer chromatography to separate the potent antifungal compounds A and B. Compound A was found highly effective against the targeted fungal pathogen with MIC 31.25 μg ml−1, followed by B with MIC value of 250 μg ml−1 as compared to 7.81 μg ml−1 MIC of a commercial fungicide mancozeb. In pot trial, the soil was amended by 1, 2, and 3% dry leaf material of the test plant species. Disease incidence was significantly reduced in 3% dose.ConclusionsThis study concludes that W. somnifera contains potent antifungal compounds that can be effectively exploited for the control of A. rabiei.

Synthesis, photophysical characterisation and antimicrobial activity of a new anionic PAMAM dendrimer

A new anionic dendrimer (D1) has been synthesized and characterized by modification of a poly(amidoamine) (PAMAM) dendrimer with 3-(6-nitro-1,3-dioxo-1H-benzo[de]isoquinolin-2(3 H)-yl)propanoic acid (NI1). Its photophysical characteristics have been investigated in organic solvents of different polarity and a positive solvatochromism has been observed. The effect of the pH medium on the fluorescence intensity has been investigated and it has been shown that in the highly alkaline medium the dendrimer emits intense fluorescence. The dendrimer and its monomeric structural analogue have been loaded on a cotton fabric and the release of substances from the surface of the cotton fabric has been investigated. The compounds have been screened for antimicrobial and cytotoxic activities. They have been found more active against Gram-positive bacteria. The dendrimer exhibits slightly lower activity than the monomeric analogue, but is found to be significantly less cytotoxic. The deposited on cotton fabric D1 prevents the formation of bacterial biofilm on the fabric surface.

Bacterial cellulose aerogels: Influence of oxidation and silanization on mechanical and absorption properties

Biodegradable aerogels may help to develop eco-friendly technological pathways to increase the efficiency of chemical processes. In the present work, we describe the preparation of a novel bacterial cellulose aerogel oxidized by TEMPO, nanofibrillated in a blender, and silanized with methyltrimethoxysilane, resulting in four different types of aerogel. The aerogels produced from the double-functionalized cellulose suspension (BCOXNS) were compared to other non-oxidized (BCN and BCNS) and non-silanized (BCOXN) aerogels All aerogels were very light (density 10–14 kg.m−3) and very porous (porosity >99 %). The aerogels of BCOXNS showed better mechanical properties (tension of 13.0 kPa, modulus of elasticity of 39.4 kPa) and hydrophobicity, and could absorb organic solvents of different polarities. The BCOXNS could be recycled at least 7 times after absorbing organic solvents while retaining an absorption capacity of 83 %. This material can be used as a standard for the further development of aerogels based on bacterial biopolymers.

Heterogeneous Biocatalytic Processes of the Low-Temperature Synthesis of Esters: Selection of Organic Solvent

Processes of the low-temperature enzymatic synthesis of esters in nonaqueous media of organic solvents with participation of heterogeneous biocatalysts synthesized by the adsorption immobilization of a recombinant lipase from Thermomyces lanuginosus (Pichia pastoris producer) on macroporous carbon aerogel were investigated. The esterification reaction was conducted using individual organic solvents of different polarity, such as nonpolar ones (lоgP > 2.5) – hexadecane, hexane and toluene, and polar solvents (lоgP < 1) – diethyl ether, tert-butanol and acetone, as well as their binary mixtures of different composition, for example, a mixture of hexane with diethyl ether having the composition 1 : (1/5÷3, vol. fr.). The effect of the solvent and co-solvent nature on the properties of synthesized biocatalysts, namely the enzymatic activity and operational stability, was studied in the batch esterification of heptanoic acid (C7:0) by alcohols, particularly the polar substrates – ethanol and n-butanol, or nonpolar alcohols – n-octanol and n-hexadecanol. Activity of the synthesized biocatalysts was found to depend to a great extent on polarity of both the solvents used in the reaction and the alcohol substrates. The maximum activity of 400 EA·g–1 was observed in a medium of nonpolar and nonviscous hexane (lоgP = 2.9), whereas the minimum activity of 4 EA·g–1 – in acetone (lоgP = 0.4); esterification of heptanoic acid in the presence of tert-butanol (lоgP = 0.6) virtually did not proceed. The activity of biocatalysts was shown to depend nonmonotonically on the lоgP value of individual solvent. In the binary mixtures of organic solvents, such as hexane/diethyl ether, biocatalytic activity linearly increased with an increase in lоgPmixture; in addition, biocatalysts exhibited the maximum operational stability.

Synthesis, Photophysical Characterization, and Sensor Activity of New 1,8-Naphthalimide Derivatives.

Three new 1,8-naphthalimide derivatives M1–M3 with different substituents at the C-4 position have been synthesized and characterized. Their photophysical properties have been investigated in organic solvents of different polarity, and their fluorescence intensity was found to depend strongly on both the polarity of the solvents and the type of substituent at C-4. For compounds M1 and M2 having a tertiary amino group linked via an ethylene bridge to the chromophore system, high quantum yield was observed only in non-polar media, whereas for compound M3, the quantum efficiency did not depend on the medium polarity. The effect of different metal ions (Ag+, Ba2+, Cu2+, Co2+, Mg2+, Pb2+, Sr2+, Fe3+, and Sn2+) on the fluorescence emission of compounds M1 and M2 was investigated. A significant enhancement has been observed in the presence of Ag+, Pb2+, Sn2+, Co2+, Fe3+, as this effect is expressed more preferably in the case of M2. Both compounds have shown significant pH dependence, as the fluorescence intensity was low in alkaline medium and has been enhanced more than 20-fold in acidic medium. The metal ions and pH do not affect the fluorescence intensity of M3. Density-functional theory (DFT) and Time-dependent density-functional theory (TDDFT) quantum chemical calculations are employed in deciphering the intimate mechanism of sensor mechanism. The functional properties of M1 and M2 were compared with polyamidoamine (PAMAM) dendrimers of different generations modified with 1,8-naphthalimide.

Photophysical and antibacterial activity of light-activated quaternary eosin Y

AbstractThe functional characteristics of a new eosin dye with biocidal quaternary ammonium group (E) were studied in aqueous solution and in organic solvents of different polarity. The spectral properties depend on the nature and polarity of the respective solvents. The antimicrobial activity of compound E has been tested in vitro against Gram-negative bacteria (Escherichia coli, Acinetobacter johnsoni and Pseudomonas aeruginosa), Gram-positive bacteria (Sarcina lutea and Bacillus cereus) and the antifungal activity was tested against the yeasts Candida lipolytica in solution and after treated on cotton fabric. Broth dilution test has been used for quantitative evaluation of the antimicrobial activity of compound E against the model strains. The ability of compound E to inhibit the growth of model Gram-negative P. aeruginosa strain was assessed after 16 h of incubation in presence and absence of light. These experiments were conducted in planktonic format in solution and on cotton fabric. The results suggest that the new compound is effective in treating the relevant pathogens with better results being obtained by irradiation with light. In this case the quaternary ammonium group promotes the binding of eosin Y moiety to the bacterial cell wall thus accelerating bacterial photo inactivation.

Root Bark of Paeonia suffruticosa Extract and Its Component Methyl Gallate Possess Peroxynitrite Scavenging Activity and Anti-inflammatory Properties through NF-κB Inhibition in LPS-treated Mice.

A peroxynitrite (ONOO−)-generating system induced by 3-morpholinosydnonimine, was used to evaluate the ONOO− scavenging properties of plants that have been widely used as traditional medicine in Korea for the treatment of several diseases. The most effective medicinal plants were Paeonia suffruticosa Andrew, followed in order by Lonicera japonica Thunb., Curcuma zedoaria (Christm.) Roscoe, and Pueraria thunbergiana Benth. In addition, root bark of P. suffruticosa was partitioned with organic solvents of different polarities, and the ethyl acetate (EtOAc) fraction showed the strongest ONOO− scavenging activity. Methyl gallate, a plant-derived phenolic compound identified from the EtOAc fraction, exerted strong ONOO− scavenging activity. The in vivo therapeutic potential of methyl gallate was investigated using lipopolysaccharide-treated mice. Oral administration of methyl gallate protected against acute renal injury and exhibited potential anti-inflammatory properties through an increase in antioxidant activity and decrease in nuclear factor-kappa B activity.

Synthesis, spectral characteristics and microbiological activity of benzanthrone derivatives and their Cu(II) complexes

Two benzanthrone derivatives with an amide group (B1 and B2) attached to the C-3 atom have been synthesized and characterized by different spectral methods. The basic photophysical characteristics were investigated in organic solvents of different polarity. A batochromic shift was observed in the transition from non-polar to polar media. The influence of copper ions on the intensity of fluorescence emission was investigated and a stable copper complex with compound B2 was isolated. Its chemical structure was characterized by electronic spectroscopy, IR and EPR spectroscopy. The stoichiometry of the isolated complex was found to be at a 1: 1 ligand-copper ratio. The microbiological activity of the newly synthesized compounds against gram positive and gram negative bacteria and yeast was examined. The copper complex enhanced the antibacterial activity compared to that of the ligand.

Phytochemical analysis and antioxidant activity of different plant parts of Pellacalyx axillaris

Pellacalyx axillaris or locally known as ‘membuloh’ is a mangrove species belonging to the Rhizophoraceae family. Till date, there has been only one phytochemical study found on this particular plant species and that without any documentation on its biological activities. Therefore, the present work aimed to reveal the phytoconstituents and the antioxidant activity of different crude extracts from different plant parts of P. axillaris. Experimentally, three organic solvents of different polarities i.e. n-hexane, ethyl acetate and methanol were used to prepare the crude extracts from the dried leaves, twigs and barks of P. axillaris. The preliminary phytochemical screening of this species indicated the presence of terpenoids, phenolic compounds, tannins, flavonoids, alkaloids, anthraquinone glycosides and carbohydrates. The in vitro antioxidant activity of the species evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay, and ferric reducing antioxidant power (FRAP) suggested that the methanolic bark extract contained potential source of natural antioxidants. Further research into isolation of antioxidant compounds from this species is highly recommended.

Impact of solvents on the extraction and purification of vegetable dyes onto the efficiency for dye-sensitized solar cells

Eight vegetable dyes extracted from flowers, fruits and leaves abundant in the wide biodiversity of the Andes region of South America were extracted with ethanol without purification to explore as vegetable photosensitizers in dye-sensitized solar cells (DSSCs). The absorbance spectra were measured by UV–visible spectroscopy and the photoelectrical performance of the DSSCs based on these dyes with a homemade solar simulator, constructed only for educational purposes under 1 sun of illumination. The open-circuit voltages (Voc) and the short-circuit photocurrent densities (Jsc) varied from 0.39 to 0.48 V and from 0.04 to 0.56 mA cm−2, and the power conversion efficiency (PCE) ranged from 0.01 to 0.18%. Particularly, the highest Voc and PCE values of the DSSCs sensitized by the ethanol extracts of Mortiño fruit (Vaccinium floribundum) and Jamaica flowers (Hibiscus sabdariffa) without purification were presumably associated with anthocyanin, the most effective component present in both vegetable photosensitizers. Hence, various components of the ethanol extracts obtained from these two vegetable dyes were purified by liquid–liquid extraction using different organic solvents of different polarity, namely petroleum ether, chloroform, ethyl acetate, n-butanol, and distilled water. Ethyl acetate resulted as the most favorable solvent for purification of ethanol extracts from Mortiño fruit and Jamaica flowers to use as vegetable photosensitizers in DSSCs. The PCE of the DSSC fabricated with the dye extracted in ethyl acetate from Mortiño fruit achieved 0.33%, with Voc of 0.520 V and Jsc of 1.014 mA cm−2, whereas the corresponding values obtained from the dye extracted from Jamaica flowers reached 0.22% with Voc of 0.541 V and Jsc of 0.678 mA cm−2. Thus, the purification of vegetable dyes used as photosensitizer impacts the photoelectrochemical performance of DSSCs.

Effect of solvent nature on spectral properties of blue-emitting meso-propargylamino-BODIPY

The spectral and luminescent properties of meso-propargylamino-boron (III) dipyrromethenate (BODIPY 1) were studied in a wide range of organic solvents of different polarities, electron- and proton-donating abilities. Effect of organic solvents on the properties of the BODIPY 1 spectral characteristics was analyzed in details. It was shown that the fluorescence of BODIPY 1 is characterized by a high sensitivity to the nature of the solvent. It was found that the complex, which emits in the blue-green region (433–486 nm), has a high quantum yield of fluorescence (~100%) in non-polar media (cyclohexane, benzene, toluene), while in proton- and especially electron donor media, sharp fluorescence quenching (2.2–31.2 times) of the dye is observed. For a better understanding of the spectral analysis results, a quantum-chemical analysis of the molecular structure, electronic structure, and spectral characteristics of BODIPY 1 was carried out. For the first time, it was shown that BODIPY 1 fluorescence quenching in proton and electron donor media is caused by the formation of a supramolecular dye complex due to specific interactions of solvent molecules with atoms of the meso-propargylamine group. Due to practically useful spectral properties, including the sensitivity of the fluorescence to the nature of the media, BODIPY 1 is recommended as a new effective fluorescent sensor of specific electron and proton donor molecules.

Phytochemistry and Antioxydante Activity ofStevia rebaudiana

Stevia rebaudianais a perennial shrub belonging to the Asteraceae family. Recently, it has been introduced to Morocco from its native Paraguay; its molecules have a sweetening power that is about 300 times sweeter than sucrose. This characteristic makes of this plant a considerable natural noncalorific sweetener in case of hypoglycemic or low carbohydrate diet. This important interest has prompted us to make further studies on this plant. The objective of this work is to show the value ofStevia rebaudianagrown in the Larache region of Morocco by the chemical characterization and evaluation of the antioxidant activity of its extracts. A phytochemical screening was carried out to highlight the qualitative composition of secondary metabolites. This analysis showed the presence of flavonoids, tannins, oses and holosides, sterols, triterpenes, and free anthraquinones. However, the absence of alkaloids and reducing compounds has been observed. In addition, extraction of the total polyphenols was carried out by maceration using a 70% methanol–water mixture. The yield is of the order of 28.6%. Subsequently, fractionation of the crude extract was carried out by successively using three organic solvents of different polarities: chloroform, ethyl acetate, andn-butanol. Polyphenol dosage with Folin-Ciocalteu’s reagent showed that ethyl acetate fraction is richer in phenolic compounds (26.4%) than the other fractions. Flavonoids dosage with aluminum trichloride showed the richness of this plant in these compounds. The antioxidant activity of different fractions was evaluated by 2,2-diphenyl-1-picrylhydrazyl-free radical scavenging method and ferric reducing/antioxidant power method; the values of the 50% inhibitory concentrations (IC50) were determined graphically. It is equal to 0.32 mg/ml for the ethyl acetate fraction, compared to 0.08 mg/ml for the ascorbic acid used as a reference. In this study, we have shown thatStevia rebaudianais very rich in phenolic compounds and possesses a very important antioxidant power.

In vitro Determination of Antioxidant Activities of the Fractions Obtained from Adansonia Digitata L. (baobab) Stem Bark Ethanolic Extract using Different Parameters

Medicinal plants have been utilized to treat acute and chronic disorders for many years. The basis for such utilization however is based on the potential use of phytochemicals to manage a plethora of chronic diseases including cancer, inflammatory diseases and cardiovascular abnormalities. In this study, the in vitro antioxidant capacity (TAC), total phenolic content (TPC) and total flavonoids content (TFC) β-carotene bleaching inhibition assay and metal chelating activity of the fractions obtained from ethanolic extract of the stem bark of Adansonia digitata were determined using Spectrophotometric methods. Extraction was carried out using absolute ethanol and fractionation was carried out using organic solvents of different polarities, beginning from n-Hexane, ethyl-acetate, ethanol, methanol and finally distilled water. Eighteen fractions were obtained from the ethanolic extract using the solvents. Folin Ciocalteau is a mixture of phosphomolybdate and phosphotungstate which was used for the Spectrophotometric in vitro assay of the Total Phenolic Content (TPC). Total Flavonoid Contents (TFC) was determined by the aluminium colorimetric method, with quercetin as reference standard. β-Carotene bleaching inhibition assay, the metal chelating activity of the extract fractions with ferrous ions were also carried out. The results obtained from the study revealed that fractions 6 and 7 (2900.00 mg/ml TE and 2410.46 mg/ml TE) possessed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity while fraction 8 and 9 (355.56 mg/ml TE and 420.26 mg/ml TE) possessed the lowest activities. Furthermore, Fractions 10 and 13 (1415.23 mg/ml GAE and 664.76 mg/ml GAE) showed the highest total phenolic content (TPC) while fraction 16 and 9 (2.86 mg/ml GAE and 4.29 mg/ml GAE) had the lowest values respectively. Fractions 5 and 9 showed the highest Total Flavonoids Content (TFC) followed by fraction 12, and the lowest was observed in fractions 2 and18. The highest concentration for β-Carotene Bleaching Inhibition Assay was observed in fractions 12 and 9, and the lowest β-Carotene concentration was observed in fractions 7 and 8. Metal Chelating Inhibition Activity revealed that fractions 12 and 5 have the highest concentration, 7 and 8 with the lowest concentration. In conclusion, the free radicals scavenging potentials of this plant extract probably contribute to the effectiveness of the plant as a medicinal plant. The secondary metabolites in the plant have been found to be of medicinal importance both in preventive and curative medicine, especially as revealed by fractions 5, 6, 7, 10, 11 and 12, the peak of which were found in fractions 5 and 12.

Correction to: Influence of the Solvent on the Structure and Morphology of Nanoparticles Fabricated by Laser Ablation of Bulk Magnesium Targets

Ultrafine powders and colloid solutions of nanoparticles are fabricated by nanosecond pulsed laser ablation (a Nd:YAG laser, 1064 nm, 7 ns, 150 mJ, and 20 Hz) of metallic magnesium targets in water and organic solvents of different polarities (ethyl alcohol, ethyl acetate, and n-hexane). The morphology, dimensional characteristics, composition, and structure of the particles are studied by the methods of transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy depending on the solvent used. For the first time it has been demonstrated that nanostructures of magnesium oxyhydroxide Mg5O(OH)8 are formed during the ablation in water. It is established that in organic solvents, formation of hexagonal and cubic magnesium oxides is possible. Nanoparticles fabricated by the ablation in less thermostable solvents – ethyl acetate and hexane – contain carbonates.

Influence of the Solvent on the Structure and Morphology of Nanoparticles Fabricated by Laser Ablation of Bulk Magnesium Targets

Ultrafine powders and colloid solutions of nanoparticles are fabricated by nanosecond pulsed laser ablation (a Nd:YAG laser, 1064 nm, 7 ns, 150 mJ, and 20 Hz) of metallic magnesium targets in water and organic solvents of different polarities (ethyl alcohol, ethyl acetate, and n-hexane). The morphology, dimensional characteristics, composition, and structure of the particles are studied by the methods of transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy depending on the solvent used. For the first time it has been demonstrated that nanostructures of magnesium oxyhydroxide Mg5O(OH)8 are formed during the ablation in water. It is established that in organic solvents, formation of hexagonal and cubic magnesium oxides is possible. Nanoparticles fabricated by the ablation in less thermostable solvents – ethyl acetate and hexane – contain carbonates.

Prediction of partition and distribution coefficients in various solvent pairs with COSMO-RS.

Performance of COSMO-RS method as a tool for partition and distribution modeling in 20 solvent pairs-composed of neutral or acidic aqueous solution and organic solvents of different polarity, ranging from alcohols to toluene and hexane-was evaluated. Experimental partition/distribution data of lignin-related and drug-like compounds (neutral, acidic, moderately basic) were used as reference. Several aspects of partition modeling were addressed: accounting for mutual saturation of aqueous and organic phases, variability of systematic prediction errors across solvent pairs, taking solute ionization into account. COSMO-RS was found to predict extraction outcome for both ligneous and drug-like compounds in various solvent pairs fairly well without any additional empirical input. The solvent-specific systematic errors were found to be moderate, despite being statistically significant, and related to the solvent hydrophobicity. Accounting for mutual solubilities of the two liquids was proven crucial in cases where water was considerably soluble in the organic solvent. The root mean square error of a priori logP prediction varied, depending mainly on the solvent pair, from 0.2 to 0.7, overall value being 0.6 log units. The accuracy was higher in case of hydrophilic than hydrophobic solvents. The logD predictions were less accurate, due to pKa prediction being an additional source of error, and also because of the complexity of modeling the behaviour of ionic species in the two-phase system. A simple correction for partitioning of free ions was found to notably improve logD prediction accuracy in case of the most hydrophilic organic phase (butanol/water).

Two hydrazones derived from 1-aryl-3-(p-substituted phenyl)prop-2-en-1-one: synthesis, crystal structure, Hirshfeld surface analysis and in vitro biological properties.

Two chalcones were synthesized by the aldolic condensation of enolizable aromatic ketones with substituted benzaldehydes under Claisen-Schmidt reaction conditions and then treated with 2,4-dinitrophenylhydrazine to yield their corresponding hydrazones. The two (E,Z)-2,4-dinitrophenylhydrazone structures, namely (Z)-1-(2,4-dinitrophenyl)-2-[(E)-3-(4-methylphenyl)-1-phenylallylidene]hydrazine, C22H18N4O4, (H1), and (Z)-1-[(E)-3-(4-chlorophenyl)-1-(naphthalen-1-yl)allylidene]-2-(2,4-dinitrophenyl)hydrazine, C25H17ClN4O4, (H2), were isolated by recrystallization and characterized by FT-IR, UV-Vis, single-crystal and powder X-ray diffraction methods. The UV-Vis spectra of the hydrazones have been studied in two organic solvents of different polarity. It was found that (H2) has a molar extinction coefficient larger than 40000. Single-crystal X-ray diffraction analysis reveals that the molecular zigzag chains of (H1) and (H2) are interconnected through noncovalent contacts. A quantitative analysis of the intermolecular interactions in the crystal structures has been performed using Hirshfeld surface analysis. All the synthesized chalcones and hydrazones were evaluated for their antibacterial and antioxidant activities. Results indicate that the studied compounds show significant activity against Gram negative Escherichia coli strain and the chalcone 3-(4-methylphenyl)-1-phenylprop-2-en-1-one, (C1), was the most effective. In addition, only hydrazone (H1) displayed a moderate DPPH (2,2-diphenyl-1-picryl hydrazyl) scavenging efficiency.

22.4: Invited Paper: Pigmented Chemical Amplified Resist in Ultra‐fine resolution Color Filter Application: Positive Versus Negative Tone

Positive and negative tone chemical amplified resist (CAR),1 pigmented with high brightness and contrast, were composed with poly(4‐hydroxystyrene), or PHOST, a photochemical acid generator,2 and a melamine cross‐linker (only included in negative tone resist). At first, the compatibility between each of the components of resist was confirmed using precipitation method under 45°C, UV‐Vis absorption spectral data, Dynamic Light Scattering (DLS). The absorption properties and particle size analyses were studied in organic solvents of different polarities and the influence of solvent polarity on the wavelengths of the absorption and particle size distribution is described. Two types of chemical amplified resists, positive and negative tones, coated on a Corning EAGLE XG glass substrate followed by exposure to the UV radiation using photomasks with variously designed size patterns, post‐exposure baking (PEB, applied in negative tone resist), development with aqueous bases, were then compared in terms of pattern resolution, pattern cross‐section profiles, chromaticities, reliability tests.

Heterogeneous sensors for ammonia, amines and metal ions based on a dendrimer modified fluorescent viscose fabric

The synthesis and characterisation of a new fluorescent poly(propylene amine) dendrimer (BD) from a second generation modified with eight benzanthrone chromophore units have been reported. The photophysical characteristics of the dendrimer have been investigated in organic solvents of different polarity. The fluorescent dendrimer has been immobilized onto viscose fabric in order to obtain a heterogeneous sensor capable of detecting aliphatic amines, ammonia and metal ions in aqueous solutions. In the presence of those analytes the fluorescent textile material quenches its fluorescence. The results reveal its capacity to acts as a sensitive sensor of aliphatic amines and ammonia.

Fast identification of anticancer constituents in Forsythiae Fructus based on metabolomics approaches

An herb commonly contains hundreds of constituents. Identification of bioactive compound(s) in each herb using conventional approaches is usually inefficient and eco-unfriendly. In this study, we aimed to fast identify anticancer compounds in Forsythiae Fructus using UPLC/MS-based metabolomics analysis. We firstly fractionated Forsythiae Fructus crude extracts with organic solvents of different polarity, then the chemical profile of each fraction was analyzed by UPLC/Q-TOF/MS, and the anticancer activity profiles of all fractions were determined by MTT assay. Next, orthogonal projections to latent structures discriminant analysis (OPLS-DA) was applied to discriminate fractions with different anticancer activity to determine the compound(s) that contributes most to the anticancer activity. Betulinic acid was then identified to be the most potent anticancer compound in Forsythiae Fructus. Its predicted anticancer activity was confirmed by MTT assay. Taken together, our results demonstrated that the present integrated metabolomics strategy could be used for fast identification of anticancer compound(s) in herb extracts or other complex mixtures of chemicals.