Treatment of textile wastewater using carbon-based nanomaterials as adsorbents: a review.

Waste derived from the textile industry can contain a wide variety of pollutants of organic and inorganic natures, such as dyes (e.g., acid, basic, reactive, mordant dyes) and toxic metals (e.g., lead, chromium, cadmium). The presence of pollutants at high concentrations in textile waste makes them relevant sources of pollution in the environment. To solve this problem, various technologies have been developed for the removal of pollutants from these matrices. Thus, adsorption emerges as an efficient alternative for textile waste remediation, providing advantages as simplicity of operation, economy, possibility of using different adsorbent materials, and developing on-line systems that allow the reuse of the adsorbent during several adsorption/desorption cycles. This review will initially propose an introduction to the adsorption world, its fundamentals, and aspects related to kinetics, equilibrium, and thermodynamics. The possible mechanisms through which a pollutant can be retained on an adsorbent will be explained. The analytical techniques that offer valuable information to characterize the solid phases as well as each adsorbate/adsorbent system will be also commented. The most common synthesis techniques to obtain carbon nano-adsorbents have been also presented. In addition, the latest advances about the use of these adsorbents for the removal of pollutants from textile waste will be presented and discussed. The contributions reported in this manuscript demonstrated the use of highly efficient carbon-based nano-adsorbents for the removal of both organic and inorganic pollutants, reaching removal percentages from 65 to 100%.

Novel bionanomaterial based on Spirulina maxima algae and graphene oxide for lead microextraction and determination in water and infant beverages.

A new hybrid bionanomaterial composed of graphene oxide (GO) and Spirulina maxima (SM) algae was synthesized and applied to develop a preconcentration method based on the dispersive micro-solid phase extraction (D-µ-SPE) technique for the determination of Pb in water and infant beverages. In this work, Pb(II) was extracted with 3 mg of the hybrid bionanomaterial (GO@SM) followed by a back-extraction step using 500 µL of 0.6 mol L-1 HCl. Then, a 1.5 × 10-3 mol L-1 dithizone solution was added to the sample containing the analyte to form a purplish red-colored complex for its detection by UV-Vis spectrophotometry at 553 nm. An extraction efficiency of 98% was obtained after optimization of experimental variables such as GO@SM mass, pH, sample volume, type, and time of agitation. A detection limit of 1 µg L-1 and a relative standard deviation of 3.5% (at 5 µg L-1 Pb(II), n = 10) were achieved. The calibration linear range was obtained between 3.3 and 95 µg L-1 Pb(II). The proposed method was successfully applied for the preconcentration and determination of Pb(II) in infant beverages. Finally, the greenness degree of the D-µ-SPE method was evaluated using the Analytical GREEnness calculator (AGREE), obtaining a score of 0.62.

Biohybrid Adsorbent for the Preconcentration of Lead and Its Determination in Fruit Juices by Electrothermal Atomic Absorption Spectrometry.

BACKGROUND: Fruit juices are one of the most non-alcoholic beverages consumed in the world. Essential elements and other nutrients present in fruit juices play an important role in human well-being. However, fruit juices may also contain potentially toxic elements at trace levels, causing health risks. OBJECTIVE: The objective of this work was to develop an analytical methodology based on the preconcentration of lead using a new biodegradable hybrid material (BHM) composed of Rhodococcus erythropolis AW3 bacteria and Brassica napus hairy roots. METHODS: The BHM was implemented in an online solid-phase extraction (SPE) system for the determination of lead in fruit juices by electrothermal atomic absorption spectrometry (ETAAS). RESULTS: Effects of critical parameters on lead retention were studied. Under optimal experimental conditions, extraction efficiency higher than 99.9% and an enrichment factor of 62.5 were achieved. The dynamic capacity of the BHM was 36 mg/g, which favored the reuse of the column for at least eight biosorption-desorption cycles. The LOD and LOQ for preconcentration of 5 mL of sample were 5.0 and 16.5 ng/L lead, respectively. The RSD was 4.8% (at 1 µg/L lead and n = 10). CONCLUSION: The developed method was suitable for application to lead determination in different types of fruit juice. HIGHLIGHTS: A novel microextraction procedure based on the use of a biohybrid adsorbent. Highly sensitive determination of Pb at trace levels. Analysis of Pb in fruit juices samples. An eco-friendly microextraction technique for Pb determination.

Hybrid biomaterials to preconcentrate and determine toxic metals and metalloids: a review.

Toxic elements represent a serious threat to the environment and cause harmful effects on different environmental components, even at trace levels. These toxic elements are often difficult to detect through the typical instrumentation of an analytical laboratory because they are found at very low concentrations in matrices such as food and water. Therefore, preconcentration plays a fundamental role since it allows the effects of the matrix to be minimized, thus reaching lower detection limits and greater sensitivity of detection techniques. In recent years, solid-phase extraction has been successfully used for the preconcentration of metals as an environmentally friendly technique due to the fact that it eliminates or minimizes the use of reagents and solvents and offers reduced analysis times and low generation of waste in the laboratory. Hybrid biomaterials are low-cost, eco-friendly, and useful as efficient solid phases for the preconcentration of elements. In this review, recent investigations based on the use of hybrid biomaterials for the preconcentration and determination of toxic metals are presented and discussed, given special attention to bionanomaterials. A brief description of hybrid biomaterials often used for analytical purposes, as well as analytical techniques mostly used to characterize the hybrid biomaterials, is explained. Finally, the future prospects that encourage the search for new hybrid biomaterials are commented upon.

Removal of thallium from environmental samples using a raw and chemically modified biosorbent derived from domestic wastes.

Because of its high toxicity, thallium (Tl) causes environmental pollution even at very low concentrations. Despite its extremely high environmental risk, limited information about Tl removal from water is present on the literature. This work focused on the use of an eco-friendly and low-cost Ilex paraguariensis (yerba mate) biowaste to remove Tl from environmental water samples. Raw (YM) and L-cysteine chemically modified yerba mate (YM@LC) were used. The effect of pH and biosorbent concentration on the biosorption capacity was studied using an experimental design. The optimal experimental conditions were as follows: YM concentration 0.25 g L-1, pH 6.0, and YM@LC concentration 0.25 g L-1, pH 4.0. Kinetic studies yielded data that were in accordance with pseudo-second-order model. Equilibrium studies were also developed and indicated that the most appropriate model was that of Sips, with a maximum capacity of biosorption at 328 K of 333.4 mg g-1 for YM and 384.4 mg g-1 for YM@LC. The thermodynamic evaluation exhibited an endothermic, spontaneous, and favorable biosorption for both biosorbents. YM and YM@LC showed significant potential for Tl removal from environmental water samples.

Biosorption of crystal violet dye using inactive biomass of the fungus Diaporthe schini.

An inactive biomass of a new fungus recently discovered, Diaporthe schini, was evaluated for the biosorption of crystal violet (CV) in simulated textile effluents. The characterization assays were performed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms. The influences of pH and biosorbent dosage on the biosorption capacity were evaluated. Kinetics, equilibrium and thermodynamic studies were also carried out. Characterization techniques showed an amorphous biosorbent, with a rough surface containing irregular particles and surface area of 6.5 m2 g-1. The most adequate values of pH and biosorbent dosage were 7.5 and 0.4 g L-1, respectively. The Elovich kinetic model and the Sips equilibrium model were suitable to fit the experimental data. The biosorption capacity increased with temperature, reaching a maximum biosorption capacity of 642.3 mg g-1 at 328 K. The biosorption was a spontaneous and endothermic process. Diaporthe schini inactive biomass was an interesting biosorbent to treat colored effluents, presenting efficiency of 87% in the decolorization of a simulated dye house effluent.

Impact of double inoculation with Bradyrhizobium japonicum E109 and Azospirillum brasilense Az39 on soybean plants grown under arsenic stress.

Inoculation practice with plant growth-promoting bacteria (PGPB) has been proposed as a good biotechnological tool to enhance plant performance and alleviate heavy metal/metalloid stress. Soybean is often cultivated in soil with high arsenic (As) content or irrigated with As-contaminated groundwater, which causes deleterious effects on its growth and yield, even when it was inoculated with rhizobium. Thus, the effect of double inoculation with known PGPB strains, Bradyrhizobium japonicum E109 and Azospirillum brasilense Az39 was evaluated in plants grown in pots under controlled conditions and treated with As. First, the viability of these co-cultivated bacteria was assayed using a flow cytometry analysis using SYTO9 and propidium iodide (PI) dyes. This was performed in vitro to evaluate the bacterial population dynamic under 25 µM AsV and AsIII treatment. A synergistic effect was observed when bacteria were co-cultured, since mortality diminished, compared to each growing alone. Indole acetic acid (IAA) produced by A. brasilense Az39 would be one of the main components involved in B. japonicum E109 mortality reduction, mainly under AsIII treatment. Regarding in vivo assays, under As stress, plant growth improvement, nodule number and N content increase were observed in double inoculated plants. Furthermore, double inoculation strategy reduced As translocation to aerial parts thus improving As phytostabilization potential of soybean plants. These results suggest that double inoculation with B. japonicum E109 and A. brasilense Az39 could be a safe and advantageous practice to improve growth and yield of soybean exposed to As, accompanied by an important metalloid phytostabilization.

Magnetic ionic liquid-based dispersive liquid-liquid microextraction technique for preconcentration and ultra-trace determination of Cd in honey.

A simple, highly efficient, batch, and centrifuge-less dispersive liquid-liquid microextraction method based on a magnetic ionic liquid (MIL-DLLME) and electrothermal atomic absorption spectrometry (ETAAS) detection was developed for ultra-trace Cd determination in honey. Initially, Cd(II) was chelated with ammonium diethyldithiophosphate (DDTP) at pH 0.5 followed by its extraction with the MIL trihexyl(tetradecyl)phosphonium tetrachloroferrate(III) ([P6,6,6,14]FeCl4) and acetonitrile as dispersant. The MIL phase containing the analyte was separated from the aqueous phase using only a magnet. A back-extraction procedure was applied to recover Cd from the MIL phase using diluted HNO3 and this solution was directly injected into the graphite furnace of ETAAS instrument. An extraction efficiency of 93% and a sensitivity enhancement factor of 112 were obtained under optimal experimental conditions. The detection limit (LOD) was 0.4 ng L-1 Cd, while the relative standard deviation (RSD) was 3.8% (at 2 µg L-1 Cd and n = 10), calculated from the peak height of absorbance signals. This work reports the first application of the MIL [P6,6,6,14]FeCl4 along with the DLLME technique for the successful determination of Cd at trace levels in different honey samples. Graphical abstract Preconcentration of ultratraces of Cd in honey using a magnetic ionic liquid and dispersive liquid-liquid microextraction technique.

Intra-regional classification of grape seeds produced in Mendoza province (Argentina) by multi-elemental analysis and chemometrics tools.

The feasibility of the application of chemometric techniques associated with multi-element analysis for the classification of grape seeds according to their provenance vineyard soil was investigated. Grape seed samples from different localities of Mendoza province (Argentina) were evaluated. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of twenty-nine elements (Ag, As, Ce, Co, Cs, Cu, Eu, Fe, Ga, Gd, La, Lu, Mn, Mo, Nb, Nd, Ni, Pr, Rb, Sm, Te, Ti, Tl, Tm, U, V, Y, Zn and Zr). Once the analytical data were collected, supervised pattern recognition techniques such as linear discriminant analysis (LDA), partial least square discriminant analysis (PLS-DA), k-nearest neighbors (k-NN), support vector machine (SVM) and Random Forest (RF) were applied to construct classification/discrimination rules. The results indicated that nonlinear methods, RF and SVM, perform best with up to 98% and 93% accuracy rate, respectively, and therefore are excellent tools for classification of grapes.

Macroalgae of Iridaea cordata as an efficient biosorbent to remove hazardous cationic dyes from aqueous solutions.

In the present work, Iridaea cordata (IC), a red marine macroalgae, was used as an efficient biosorbent for the removal of crystal violet (CV) and methylene blue (MB) dyes from aqueous solutions. The effects of pH (5, 7, and 9) and IC concentration (1, 3, and 5 g L-1) on the biosorption were studied through a 32 full factorial design. Under the optimal conditions (pH: 7, biosorbent concentration: 1 g L-1), biosorption kinetic studies were developed and the obtained experimental data were evaluated by pseudo-first order and pseudo-second order models. The results showed that the pseudo-second order model was in agreement with the experimental kinetic data for both dyes. Equilibrium studies were also carried out, and results exhibited good concordance with the Brunauer-Emmett-Teller isotherm. The biosorption capacities were 36.5 and 45.0 mg g-1 for CV and MB dyes, respectively. The dye removal percentages were around 75% for CV and 90% for MB. Thermodynamically, the biosorption process proved to be exothermic, spontaneous, and favorable. These results showed that IC biomass is a promising biosorbent for removal of CV and MB dyes from aqueous solutions.

Powdered grape seeds (PGS) as an alternative biosorbent to remove pharmaceutical dyes from aqueous solutions.

An alternative, low-cost and efficient biosorbent, powdered grape seeds (PGS), was prepared from wastes of a wine industry, and used to remove brilliant blue (BB) and amaranth red (AR) dyes from aqueous solutions. The biosorbent was properly characterized before and after the biosorption operation. The potential of PGS to remove BB and AR dyes was investigated thought kinetic, isotherm and thermodynamic studies. The biosorption of BB and AR was favored at pH 1.0 using biosorbent dosage of 0.500 g L-1, being attained more than 85% of removal percentage. For BB and AR dyes, pseudo-second-order and Elovich models were able to explain the biosorption kinetic. The biosorption equilibrium of BB on PGS was well represented by the Langmuir model, while for AR, the Sips model was the most adequate. The maximum biosorption capacities were 599.5 and 94.2 mg g-1 for BB and AR, respectively. The biosorption of BB and AR on PGS was a spontaneous, favorable and endothermic process. These findings indicated that PGS is a low-cost and efficient biosorbent, which can be used to treat dye containing waters.

New Rimocidin/CE-108 Derivatives Obtained by a Crotonyl-CoA Carboxylase/Reductase Gene Disruption in Streptomyces diastaticus var. 108: Substrates for the Polyene Carboxamide Synthase PcsA.

The rimJ gene, which codes for a crotonyl-CoA carboxylase/reductase, lies within the biosynthetic gene cluster for two polyketides belonging to the polyene macrolide group (CE-108 and rimocidin) produced by Streptomyces diastaticus var. 108. Disruption of rimJ by insertional inactivation gave rise to a recombinant strain overproducing new polyene derivatives besides the parental CE-108 (2a) and rimocidin (4a). The structure elucidation of one of them, CE-108D (3a), confirmed the incorporation of an alternative extender unit for elongation step 13. Other compounds were also overproduced in the fermentation broth of rimJ disruptant. The new compounds are in vivo substrates for the previously described polyene carboxamide synthase PcsA. The rimJ disruptant strain, constitutively expressing the pcsA gene, allowed the overproduction of CE-108E (3b), the corresponding carboxamide derivative of CE-108D (3a), with improved pharmacological properties.

Functional Dependence between Septal Protein SepJ from Anabaena sp. Strain PCC 7120 and an Amino Acid ABC-Type Uptake Transporter.

UNLABELLED: In the diazotrophic filaments of heterocyst-forming cyanobacteria, two different cell types, the CO2-fixing vegetative cells and the N2-fixing heterocysts, exchange nutrients, including some amino acids. In the model organism Anabaena sp. strain PCC 7120, the SepJ protein, composed of periplasmic and integral membrane (permease) sections, is located at the intercellular septa joining adjacent cells in the filament. The unicellular cyanobacterium Synechococcus elongatus strain PCC 7942 bears a gene, Synpcc7942_1024 (here designated dmeA), encoding a permease homologous to the SepJ permease domain. Synechococcus strains lacking dmeA or lacking dmeA and expressing Anabaena sepJ were constructed. The Synechococcus dmeA mutant showed a significant 22 to 32% decrease in the uptake of aspartate, glutamate, and glutamine, a phenotype that could be partially complemented by Anabaena sepJ. Synechococcus mutants of an ATP-binding-cassette (ABC)-type transporter for polar amino acids showed >98% decreased uptake of glutamate irrespective of the presence of dmeA or Anabaena sepJ in the same strain. Thus, Synechococcus DmeA or Anabaena SepJ is needed to observe full (or close to full) activity of the ABC transporter. An Anabaena sepJ deletion mutant was significantly impaired in glutamate and aspartate uptake, which also in this cyanobacterium requires the activity of an ABC-type transporter for polar amino acids. SepJ appears therefore to generally stimulate the activity of cyanobacterial ABC-type transporters for polar amino acids. Conversely, an Anabaena mutant of three ABC-type transporters for amino acids was impaired in the intercellular transfer of 5-carboxyfluorescein, a SepJ-related property. Our results unravel possible functional interactions in transport elements important for diazotrophic growth. IMPORTANCE: Membrane transporters are essential for many aspects of cellular life, from uptake and export of substances in unicellular organisms to intercellular molecular exchange in multicellular organisms. Heterocyst-forming cyanobacteria such as Anabaena represent a unique case of multicellularity, in which two cell types exchange nutrients and regulators. The SepJ protein located at the intercellular septa in the filaments of Anabaena contains a permease domain of the drug/metabolite transporter (DMT) superfamily that somehow contributes to intercellular molecular transfer. In this work, we have found that SepJ stimulates the activity of a polar amino acid uptake transporter of the ATP-binding-cassette (ABC) superfamily, which could itself affect an intercellular transfer activity related to SepJ, thus unraveling possible functional interactions between these different transporters.

Stability of iron-quercetin complexes in synthetic wine under in vitro digestion conditions.

UNLABELLED: Wine is a dietary source of polyphenolic compounds with reported health benefits when moderately consumed. Several of these compounds can associate with metals forming complexes. Therefore, this work was conducted to reach a better understanding of the nature and chemical stability of wine-derived Fe(3+)-quercetin complexes in a digestion model. The stability of the complexes in a synthetic (simulated) wine was studied before and after in vitro gastric and intestinal digestions by high-performance liquid chromatography (HPLC) with UV-Vis detection. Metal determination was performed by atomic absorption spectrometry (ETAAS) to evaluate possible dissociation of complexes. During HPLC analysis all peaks eluted from the chromatographic column were collected, acidified, and analyzed by ETAAS. The results showed that complexes remain substantially stable after gastric digestion conditions, with recoveries of 84% to 90%. Although metal complexes were partially degraded during intestinal digestion, 41% to 45% of the Fe(3+)-quercetin complexes was recovered. PRACTICAL APPLICATION: This work reveals the chemical stability of Fe3+­quercetin complexes in synthetic wines after an in vitro gastrointestinal digestion. The knowledge of this process would be useful to understand the bioavailability of these compounds.

Polymer-supported ionic liquid solid phase extraction for trace inorganic and organic mercury determination in water samples by flow injection-cold vapor atomic absorption spectrometry.

A simple and green technique named polymer-supported ionic liquid solid phase extraction (PSIL-SPE) was developed for mercury (Hg) species determination. Inorganic Hg (InHg) species was complexed with chloride ions followed by its introduction into a flow injection on-line system to quantitatively retain the anionic chlorocomplex (HgCl4(2-)) in a column packed with CYPHOS(®) IL 101-impregnated resin. The trapped InHg was then reduced with stannous chloride (SnCl2) and eluted with the same flow of reducing agent followed by cold vapor atomic absorption spectrometry (CV-AAS) detection. Organic mercury species (OrgHg) did not interact with the impregnated resin and were not retained into the column. Total concentration of OrgHg was evaluated by difference between total Hg and InHg concentration. A 95% extraction efficiency was achieved for InHg when the procedure was developed under optimal experimental conditions. The limit of detection obtained for preconcentration of 40 mL of sample was 2.4 ng L(-1) InHg. The relative standard deviation (RSD) was 2.7% (at 1 µg L(-1) InHg and n=10) calculated from the peak height of absorbance signals (Gaussian-shape and reproducible peaks). This work reports the first polymer-supported IL solid phase extraction approach implemented in a flow injection on-line system for determination of Hg species in mineral, tap and river water samples.

Bioanalytical separation and preconcentration using ionic liquids.

Ionic liquids (ILs) are novel solvents that display a number of unique properties, such as negligible vapor pressure, thermal stability (even at high temperatures), favorable viscosity, and miscibility with water and organic solvents. These properties make them attractive alternatives to environmentally unfriendly solvents that produce volatile organic compounds. In this article, a critical review of state-of-the-art developments in the use of ILs for the separation and preconcentration of bioanalytes in biological samples is presented. Special attention is paid to the determination of various organic and inorganic analytes--including contaminants (e.g., pesticides, nicotine, opioids, gold, arsenic, lead, etc.) and functional biomolecules (e.g., testosterone, vitamin B12, hemoglobin)--in urine, blood, saliva, hair, and nail samples. A brief introduction to modern microextraction techniques based on ILs, such as dispersive liquid-liquid microextraction (DLLME) and single-drop microextraction (SDME), is provided. A comparison of IL-based methods in terms of their limits of detection and environmental compatibilities is also made. Finally, critical issues and challenges that have arisen from the use of ILs in separation and preconcentration techniques are also discussed.

Liquid-liquid microextraction based on a dispersion of Pd nanoparticles combined with ETAAS for sensitive Hg determination in water samples.

A novel and highly efficient microextraction methodology based on the use of palladium nanoparticles (Pd NPs) was developed for the preconcentration and determination of Hg in water samples. Selective separation of the analyte was achieved by application of dodecanethiolate-coated Pd monolayer-protected clusters (C12S Pd MPCs) in a liquid-liquid microextraction technique (LLME). A volume of 20 µL of toluene phase containing C12S Pd MPCs was used for extraction and final phase was injected in an electrothermal atomic absorption spectrometer (ETAAS) for Hg detection. The effects of different variables, such as sample volume, extraction time, and NPs dispersion volume were carefully studied. A sensitivity enchancement factor of 95 was obtained under optimal experimental conditions. Furthermore, low detection limit (7.5 ng L(-1)) and good precision (relative standard deviation of 4.1% at 0.25 µg L(-1) Hg and n=10) were achieved. The proposed method can be considered as a rapid, cost-effective, and efficient alternative for Hg determination in water samples like river, lake, mineral and tap water.

Sensitive determination of thallium species in drinking and natural water by ionic liquid-assisted ion-pairing liquid-liquid microextraction and inductively coupled plasma mass spectrometry.

A fast and simple method involving separation and determination of thallium (Tl) species, based on novel ionic liquid-assisted ion pairing dispersive liquid-liquid microextraction (DLLME) method, was developed. Initially, Tl(III) was selectively complexed with chloride ion to form [TlCl(4)](-) chlorocomplex. Subsequently, tetradecyl(trihexyl)phosphonium chloride ionic liquid (CYPHOS(®) IL 101) was used to form the ion-pair with [TlCl(4)](-) anion followed by extraction. The DLLME procedure was developed by dispersing 80 µL of carbon tetrachloride with 100 µL of ethanol added to the aqueous solution. After DLLME, the upper aqueous phase containing Tl(I) only was removed and analysed by inductively coupled plasma-mass spectrometry (ICP-MS). In contrast to Tl(III), Tl(I) species does not form neither stable nor anionic complexes with chloride ions and it was not extracted into the organic phase. Total Tl concentration was obtained by direct introduction of sample into ICP-MS instrument. The calibration graph for the analyte was linear with a correlation coefficient of 0.9989. Under optimal conditions, detection limit of Tl species was 0.4 ng L(-1). The relative standard deviation (n=10) at 1 ng mL(-1) Tl concentration level was 1.3% for Tl(I) and 1.5% for Tl(III). The method was successfully applied for fast speciation analysis of Tl at ultratrace levels in real water samples.

Arsenic speciation analysis in mono-varietal wines by on-line ionic liquid-based dispersive liquid-liquid microextraction.

A highly efficient separation and pre-concentration method for arsenic species determination, based on ionic liquid (IL) dispersive microextraction technique implemented in a flow analysis system, is proposed. Highly selective separation of arsenite species [As(III)] was achieved by chelation with sodium diethyldithiocarbamate (DDTC) followed by dispersion with 40 mg of 1-octyl-3-methylimidazolium hexafluorophosphate ([C(8)mim][PF(6)]) IL. Analyte extraction, retention and separation of IL phase were achieved with a packed microcolumn and As(III) was determined in eluent solution by electrothermal atomic absorption spectrometry (ETAAS). Concentration of As(V) was deduced by the difference between total inorganic arsenic and As(III). Thus, determination of total arsenic was performed by previous degradation of organo-arsenic species, followed by a reduction. Under optimal conditions, As(III) extraction efficiency was 100% and a sensitivity enhancement factor of 46 was obtained with only 4.0 ml of sample The method was successfully applied for arsenic speciation studies in mono-varietal wines.

Differential trypanocidal activity of novel macrolide antibiotics; correlation to genetic lineage.

Here we report the systematic study of the anti-trypanocidal activity of some new products derived from S. diastatus on 14 different T. cruzi strains spanning the six genetic lineages of T. cruzi. As the traditional growth inhibition curves giving similar IC(50) showed great differences on antibiotic and lineage tested, we decided to preserve the wealth of information derived from each inhibition curve and used an algorithm related to potency of the drugs, combined in a matrix data set used to generate a cluster tree. The cluster thus generated based just on drug susceptibility data closely resembles the phylogenies of the lineages derived from genetic data and provides a novel approach to correlate genetic data with phenotypes related to pathogenesis of Chagas disease. Furthermore we provide clues on the drugs mechanism of action.