Wax screen-printable ink for massive fabrication of negligible-to-nil cost fabric-based microfluidic (bio)sensing devices for colorimetric analysis of sweat.

Fabric-based microfluidic analytical devices (μADs) have emerged as a promising material for replacing paper μADs thanks to their superior properties in terms of stretchability, mechanical strength, and their wide scope of applicability in wearable devices or embedded in garments. The major obstacle in their widespread use is the lack of a technique enabling their massive fabrication at a negligible-to-nil cost. In response, we report the development of a wax ink with proper thixotropic and hydrophobic properties, fully compatible with automatic screen-printing that allows the one step massive fabrication of microfluidics on a cotton/elastane fabric, with a printing resolution 400 μm (hydrophilic channel) and 1000 μm (hydrophobic barrier), without being necessary any post curing.

Sustainable production of a new generation biofuel by lipase-catalyzed esterification of fatty acids from liquid industrial waste biomass.

In this work we suggest a methodology comprising the design and use of cost-effective, sustainable, and environmentally friendly process for biofuel production compatible with the market demands. A new generation biofuel is produced using fatty acids, which were generated from acidogenesis of industrial wastes of bioethanol distilleries, and esterified with selected alcohols by immobilized Candida antarctica Lipase-B. Suitable reactors with significant parameters and conditions were studied through experimental design, and novel esterification processes were suggested; among others, the continuous removal of the produced water was provided.

Effects of anti-androgens cyproterone acetate, linuron, vinclozolin, and p,p'-DDE on the reproductive organs of the copepod Acartia tonsa.

The study was performed to detect the effects of anti-androgenic compounds on the reproduction. In this paper alterations observed in the marine calanoid copepod Acartia tonsa exposed to environmental concentrations of cyproterone acetate (CPA), linuron (LIN), vinclozolin (VIN), and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) for 21 days covering a full life cycle are described. Histological alterations were studied with a focus on reproductive organs, gonad and accessory sexual glands.

Chemometric optimization of dispersive suspended microextraction followed by gas chromatography-mass spectrometry for the determination of polycyclic aromatic hydrocarbons in natural waters.

A dispersive suspended microextraction (DSME) method coupled with gas chromatography-mass spectrometry (GC-MS) was developed and validated for the simultaneous determination of ten polycyclic aromatic hydrocarbons in real water samples. The optimization of the method was achieved with a 2(7-4) Plackett-Burman design, while the significant factors were optimized using a central composite design (CCD). The parameters that were studied included the sample volume, organic solvent volume, extraction time, restoration time and organic solvent.

Residues of selected polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP) in postmortem lungs from Epirus, northwestern Greece.

Organochlorine (OC) pesticides and polychlorinated biphenyls (PCB) are compounds characterized as persistent organic pollutants (POP) in the environment. These compounds are monitored globally since they enter the human body and accumulate in tissues, resulting in consequent adverse effects. In this study concentrations of selected OC compounds were determined in human autopsy lungs from Epirus, a relatively restricted region in northwestern Greece.

Evaluation of magnetic nanoparticles to serve as solid-phase extraction sorbents for the determination of endocrine disruptors in milk samples by gas chromatography mass spectrometry.

A rapid magnetic solid-phase extraction (MSPE) is proposed based on C18-functionalized magnetic silica nanoparticles as sorbents, for the determination of endocrine disruptors - 20 organochlorine pesticides and 6 polychlorinated biphenyls - in milk samples. Magnetic nanoparticles are characterized by several techniques, such as Scanning Electron Microscopy, X-Ray diffraction, Brunauer-Emmett-Teller and Fourier transform-infrared. The MSPE is performed by dispersion of the Fe3O4@SiO2@C18 nanoparticles in milk samples with sonication, after protein precipitation.

Effects of methyltestosterone, letrozole, triphenyltin and fenarimol on histology of reproductive organs of the copepod Acartia tonsa.

The marine calanoid copepod Acartia tonsa was exposed to methyltestosterone (MET, 1.6-126 μg L(-1)), letrozole (LET, 10-1000 μg L(-1)), triphenyltin chloride (TPT, 0.0014-0.

Evaluation of matrix solid-phase dispersion extraction for the determination of polycyclic aromatic hydrocarbons in household dust with the aid of experimental design and response surface methodology.

A simple, fast, and inexpensive procedure for sample preparation based on matrix solid-phase dispersion was developed for the determination of Environmental Protection Agency 16 priority polycyclic aromatic hydrocarbons in indoor dust samples. Parameters that affect the extraction efficiency such as type of dispersant, elution solvent, and solvent volume were evaluated and optimized with the aid of experimental design and response surface methodology. Analysis was performed by HPLC coupled with UV-Vis diode array detector (UV-DAD).

Development and application of chemometric-assisted dispersive liquid-liquid microextraction for the determination of suspected fragrance allergens in water samples.

A simple and green method based on dispersive liquid-liquid microextraction, mated to chemometrics and followed by mass spectrometric detection for the determination of suspected fragrance allergens in water samples is developed and assessed in this work. Volume of extraction and disperser solvent, pH, ionic strength, extraction time, sample volume, as well as centrifugation time were initially optimized in a fractional factorial design. The obtained significant factors were optimized by using a central composite design and the quadratic model between the dependent and the independent variables was built.

Determination of organochlorine pesticides and polychlorinated biphenyls in post-mortem human lung by matrix solid-phase dispersion with the aid of response surface methodology and desirability function.

A matrix solid-phase dispersion (MSPD) method for the simultaneous determination of 20 organochlorine pesticides (OCPs) (aldrin, endrin, dieldrin, α-BHC, β-BHC, γ-BHC, δ-BHC, α-chlordane, γ-chlordane, p,p'-DDE, p,p'-DDT, p,p'-DDD, endosulfan I, endosulfan II, endosulfan sulfate, endrin aldehyde, heptachlor, heptachlor epoxide, endrin ketone and methoxychlor) and six polychlorinated biphenyl (PCB) congeners (PCB 28, 52, 101, 138, 153 and 180) in post-mortem human lung has been developed and validated. Response surface methodology (RSM) and desirability function were employed to optimize the extraction conditions of MSPD. Extraction was carried out using Florisil (2.

Effect of chromatographic parameters and detector settings on the response of HILIC-evaporative light-scattering detection system using experimental design approach and multicriteria optimization methodology.

Four polar compounds, i.e. pantothenic acid, inositol, taurine and caffeine were used as probe solutes in conjunction with chemometric methods to find out meaningful implications of chromatographic conditions and detector settings on the system performance.

Photocatalytic degradation using design of experiments: a review and example of the Congo red degradation.

The use of chemometric methods such as response surface methodology (RSM) based on statistical design of experiments (DOEs) is becoming increasingly widespread in several sciences such as analytical chemistry, engineering and environmental chemistry. Applied catalysis, is certainly not the exception. It is clear that photocatalytic processes mated with chemometric experimental design play a crucial role in the ability of reaching the optimum of the catalytic reactions.

Application of chemometric assisted dispersive liquid-liquid microextraction to the determination of personal care products in natural waters.

A rapid and simple method for the determination of two phthalates and five polycyclic musks in water samples using dispersive liquid-liquid microextraction (DLLME) mated to chemometrics and coupled to GC-MS was developed. Volume of extraction (CCl4) and disperser solvent (MeOH), pH, ionic strength, extraction time, centrifugation time as well as centrifugation speed were optimized in a 2(7-4) Plackett-Burman design. The obtained significant factors were optimized by using a central composite design (CCD) and the quadratic model between the dependent and the independent variables was built.

An experimental design approach employing artificial neural networks for the determination of potential endocrine disruptors in food using matrix solid-phase dispersion.

Matrix solid-phase dispersion (MSPD) as a sample preparation method for the determination of two potential endocrine disruptors, linuron and diuron and their common metabolites, 1-(3,4-dichlorophenyl)-3-methylurea (DCPMU), 1-(3,4-dichlorophenyl) urea (DCPU) and 3,4-dichloroaniline (3,4-DCA) in food commodities has been developed. The influence of the main factors on the extraction process yield was thoroughly evaluated. For that purpose, a 3 fractional factorial design in further combination with artificial neural networks (ANNs) was employed.

Determination of pesticides and toxic potency of rainwater samples in western Greece.

Rainwater samples from four municipalities located in Achaia Prefecture, Greece, were collected from March to September 2006. The toxic potency of pollutants present in 36 rainwater samples was tested using Daphnia pulex. The pesticide determination was conducted with GC-MS.

Determination of the pesticides considered as endocrine-disrupting compounds (EDCs) by solid-phase extraction followed by gas chromatography with electron capture and mass spectrometric detection.

An SPE method followed by GC-electron capture detection (ECD) with confirmation by MS for the trace determination of four pesticides considered as endocrine-disrupting compounds (EDCs) in natural waters and sediments has been developed. Target analytes, fenarimol, fenvalerate, pendimethalin, and vinclozolin, belong to different chemical groups and are used mainly in agriculture. In the present study, analysis employs an offline SPE step for the extraction of the target analytes from natural waters.

Determination of UV-filter residues in bathing waters by liquid chromatography UV-diode array and gas chromatography-mass spectrometry after micelle mediated extraction-solvent back extraction.

A preconcentration methodology utilizing the cloud point phenomenon is described in this study for the determination of sunscreen agent residues in bathing waters by reversed phase liquid chromatography with UV detection and gas chromatography (GC) with mass spectrometric (MS) detection. The method employs the entrapment of the analytes in the micelles of the non-ionic surfactant TX-114, upon increase of the solution temperature to 60 degrees C. The analytes are either re-extracted or back extracted from the final micellar extract into appropriate organic solvents, a procedure that facilitates the direct application of the method not only with liquid chromatography but mostly importantly with gas chromatographic analysis.

Metolachlor photodegradation study in aqueous media under natural and simulated solar irradiation.

To elucidate the photochemical behavior of pesticide metolachlor, degradation was carried out in aqueous media of different compositions such as sea, river, lake, and distilled water under natural and simulated solar irradiation. In addition, the effect of important constituents of natural water such as dissolved organic matter (DOM, isolated from Pamvotis Lake) and nitrate ions was also examined. It was found that photodegradation proceeds via a pseudo-first-order reaction in all cases.

Determination of residues of UV filters in natural waters by solid-phase extraction coupled to liquid chromatography-photodiode array detection and gas chromatography-mass spectrometry.

This study describes a procedure for the enrichment, separation and quantification of four major UV filters in natural waters. Solid-phase extraction combined with liquid chromatography and photodiode array detection (LC-UV-DAD), and gas chromatography with mass spectroscopy (GC-MS) were employed for the analyses. LC of the four compounds with surfactant-modified hydro-organic eluents gave satisfactory resolution of overlapping peaks.

Determination of antifouling compounds in marine sediments by solid-phase microextraction coupled to gas chromatography-mass spectrometry.

Solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry was applied to determine the antifouling biocides chlorothalonil, dichlofluanid, sea nine 211 and irgarol 1051 in marine sediments. Two experimental approaches were selected before the submission of the aqueous extracts to SPME prior to GC determination. The extraction of the biocides from the sediment samples was conducted using (a) water (containing 5%, v/v, acetone) and (b) acetone which was then diluted with water to give a 5% (v/v) content.

Survey for the occurrence of antifouling paint booster biocides in the aquatic environment of Greece.

Since the restriction imposed by European Union regulations on the use of TBT-based antifouling paints on boats below 25 m in length, new terms have been introduced in the 'small boat' market. Replacement products are generally based on copper metal oxides and organic biocides. Several studies have demonstrated the presence of these biocides in European ports and marinas of Spain, France, Germany and the United Kingdom.

Study of chlorothalonil photodegradation in natural waters and in the presence of humic substances.

Photodegradation of chlorothalonil was studied in different natural waters (sea, river and lake) as well as in distilled water under natural and simulated solar irradiation. The effect of dissolved organic matter (DOM) such as humic and fulvic substances on the photodegradation rate of chlorothalonil was also studied in simulated sunlight. The presence of DOM enhanced the photodegradation of chlorothalonil with the exception of seawater.

Application of solid-phase microextraction in the monitoring of priority pesticides in the Kalamas River (N.W. Greece).

A solid-phase microextraction (SPME) method was applied to an extended monitoring survey of priority pesticides for the European Union for a period of 12 months in water of the Kalamas River (Epirus region of northwestern Greece) in order to determine their concentrations and seasonal variations. Polydimethylsiloxane-coated fiber (100 microm) was used. The samples were screened using gas chromatography with flame thermionic detection.

Photocatalytic degradation of propachlor in aqueous TiO2 suspensions. Determination of the reaction pathway and identification of intermediate products by various analytical methods.

The light-induced degradation of propachlor (2-chloro-N-isopropylacetanilide) under simulated solar irradiation has been investigated in aqueous solutions containing TiO2 suspensions as photocatalysts. The study focuses on the identification of possible intermediate products and the determination of inorganic ions formed during the process, using several powerful analytical techniques such as gas chromatography mass-spectrometry (GC-MS) and ion chromatography. The primary degradation of propachlor has been a fast process with a half-live time of 2.

Aquatic phototransformation study of the antifouling agent Sea-Nine 211: identification of byproducts and the reaction pathway by gas chromatography-mass spectroscopy.

The photochemical behaviour of the biocide Sea-Nine 211 was carried out in order to investigate several transformation products formed in different environmental matrices and under different conditions. Sea-Nine 211 photodecomposition was performed under laboratory conditions using a xenon light source and under natural sunlight conditions in sea, river, lake as well as in distilled water. In order to examine the effect of dissolved organic matter (DOM), the phototransformation of the tested biocide was studied also in the presence of various concentrations of humic and fulvic acids.