Abiotic and biotic remediation of chlorinated ethenes (CEs) in groundwater from a real contaminated site was studied using biochar-based composites containing nanoscale zero-valent iron (nZVI/BC) and natural resident microbes/specific CE degraders supported by a whey addition. The material represented by the biochar matrix decorated by isolated iron nanoparticles or their aggregates, along with the added whey, was capable of a stepwise dechlorination of CEs. The tested materials (nZVI/BC and BC) were able to decrease the original TCE concentration by 99% in 30 days. Nevertheless, regarding the transformation products, it was clear that biotic as well as abiotic transformation mechanisms were involved in the transformation process when nonchlorinated volatiles (i.e., methane, ethane, ethene, and acetylene) were detected after the application of nZVI/BC and nZVI/BC with whey. The whey addition caused a massive increase in bacterial biomass in the groundwater samples (monitored by 16S rRNA sequencing and qPCR) that corresponded with the transformation of trichloro- and dichloro-CEs, and this process was accompanied by the formation of less chlorinated products. Moreover, the biostimulation step also eliminated the adverse effect caused by nZVI/BC (decrease in microbial biomass after nZVI/BC addition). The nZVI/BC material or its aging products, and probably together with vinyl chloride-respiring bacteria, were able to continue the further reductive dechlorination of dichlorinated CEs into nonhalogenated volatiles. Overall, the results of the present study demonstrate the potential, feasibility, and environmental safety of this nanobioremediation approach.
- Klíčová slova
- Biochar, Chlororespiration, Groundwater, Nano zero-valent iron, Nanobioremediation,
- MeSH
- chemické látky znečišťující vodu * MeSH
- dřevěné a živočišné uhlí MeSH
- podzemní voda * MeSH
- RNA ribozomální 16S genetika MeSH
- rozpouštědla MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biochar MeSH Prohlížeč
- chemické látky znečišťující vodu * MeSH
- dřevěné a živočišné uhlí MeSH
- RNA ribozomální 16S MeSH
- rozpouštědla MeSH
At present, both native and immobilized nanoparticles are of great importance in many areas of science and technology. In this paper, we have studied magnetic iron oxide nanoparticles and their aggregates bound on woven cotton textiles employing two simple modification procedures. One modification was based on the treatment of textiles with perchloric-acid-stabilized magnetic fluid diluted with methanol followed by drying. The second procedure was based on the microwave-assisted conversion of ferrous sulfate at high pH followed by drying. The structure and functional properties of these modified textiles were analyzed in detail. Scanning electron microscopy of native and modified textiles clearly showed the presence of iron oxide nanoparticles on the surface of the modified cotton fibers. All of the modified textile materials exhibited light to dark brown color depending on the amount of the bound iron oxide particles. Magnetic measurements showed that the saturation magnetization values reflect the amount of magnetic nanoparticles present in the modified textiles. Small-angle X-ray and neutron scattering measurements were conducted for the detailed structural characterization at the nanoscale of both the native and magnetically modified textiles, and different structural organization of nanoparticles in the two kinds of textile samples were concluded. The textile-bound iron oxide particles exhibited peroxidase-like activity when the N,N-diethyl-p-phenylenediamine sulfate salt was used as a substrate; this nanozyme activity enabled rapid decolorization of crystal violet in the presence of hydrogen peroxide. The deposition of a sufficient amount of iron oxide particles on textiles enabled their simple magnetic separation from large volumes of solutions; if necessary, the magnetic response of the modified textiles can be simply increased by incorporation of a piece of magnetic iron wire. The simplicity of the immobilized nanozyme preparation and the low cost of all the precursors enable its widespread application, such as decolorization and degradation of selected organic dyes and other important pollutants. Other types of textile-bound nanozymes can be prepared and used as low-cost catalysts for a variety of applications.
- Klíčová slova
- cotton woven textile, iron oxide particles, magnetic fluid, microwave-assisted synthesis, nanozyme, peroxidase-like activity,
- MeSH
- bavlněné vlákno * MeSH
- enzymy imobilizované chemie metabolismus MeSH
- magnetické nanočástice chemie MeSH
- nanokompozity chemie MeSH
- peroxidasy * chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- enzymy imobilizované MeSH
- magnetické nanočástice MeSH
- peroxidasy * MeSH
The determination of contaminants of emerging concern (CECs) in environmental samples has become a challenging and critical issue. The present work focuses on miniaturized analytical strategies reported in the literature for the determination of CECs. The first part of the review provides brief overview of CECs whose monitoring in environmental samples is of particular significance, namely personal care products, pharmaceuticals, endocrine disruptors, UV-filters, newly registered pesticides, illicit drugs, disinfection by-products, surfactants, high technology rare earth elements, and engineered nanomaterials. Besides, an overview of downsized sample preparation approaches reported in the literature for the determination of CECs in environmental samples is provided. Particularly, analytical methodologies involving microextraction approaches used for the enrichment of CECs are discussed. Both solid phase- and liquid phase-based microextraction techniques are highlighted devoting special attention to recently reported approaches. Special emphasis is placed on newly developed materials used for extraction purposes in microextraction techniques. In addition, recent contributions involving miniaturized analytical flow techniques for the determination of CECs are discussed. Besides, the strengths, weaknesses, opportunities and threats of point of need and portable devices have been identified and critically compared with chromatographic methods coupled to mass chromatography. Finally, challenging aspects regarding miniaturized analytical methods for determination of CECs are critically discussed.
- Klíčová slova
- Emerging contaminants, Microextraction, Microfluidics, Millifluidics, Miniaturization, Sample preparation,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Novel modern easily feasible methods for direct evaluation of a new, simple preconcentration analytical procedure have been developed. Two types of smartphone image analysis applications (ON Color Measure and Color Lab) were evaluated to obtain RGB and HSV color spaces data for the quantification of Magnetic textile solid phase extraction of colored compounds (e.g. water-soluble organic dyes). Both direct measurement of color spaces values via the smartphone camera and image analysis of the photograph can be used successfully. The obtained data were similar to those obtained by previously examined professional ImageJ software. The saturation (S) values of the HSV color space are directly proportional to the concentrations of the analyzed dye.
- Klíčová slova
- Analytical chemistry, Biotechnology, Dyes, Environmental science, Image analysis, Magnetic textile solid phase extraction, Smartphones,
- Publikační typ
- časopisecké články MeSH
Urea, as an end product of protein metabolism and an abundant polar compound, significantly complicates the metabolomic analysis of urine by GC-MS. We developed a sample preparation method removing urea from urine samples prior the GC-MS analysis. The method based on urease immobilized on magnetic microparticles was compared with the others that are conventionally used (liquid-liquid extraction, free urease protocol), and samples without any treatment. To study the impact of sample preparation approaches on the quality of analytical data, we employed comprehensive metabolomic analysis (using both GC-MS and LC-MS/MS platforms) of standard material based on human urine. Multivariate statistical analysis has shown that immobilized urease treatment provides similar results to a free urease approach. However, significant alterations in the profiles of metabolites were observed in the samples without any treatment and after the extraction. Compared to other approaches that were tested, the immobilization of urease on microparticles reduces both the number of artifacts and the variability of the metabolites (average CV of extraction 19.7%, no treatment 11.4%, free urease 5.0%, and immobilized urease 2.5%). The method that was developed was applied in a GC-MS metabolomic experiment of glutaric aciduria type I, where both known diagnostically important biomarkers and unknowns, as the most discriminating compounds, were found.
- Klíčová slova
- GC–MS, Immobilized urease, Metabolomics, Urine sample preparation,
- MeSH
- analýza hlavních komponent MeSH
- chromatografie kapalinová metody MeSH
- enzymy imobilizované moč MeSH
- glutaryl-CoA-dehydrogenasa nedostatek metabolismus MeSH
- lidé MeSH
- magnetické jevy * MeSH
- metabolické nemoci mozku metabolismus MeSH
- metabolom MeSH
- metabolomika metody MeSH
- metody pro přípravu analytických vzorků * MeSH
- močovina metabolismus MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí metody MeSH
- reprodukovatelnost výsledků MeSH
- studie proveditelnosti MeSH
- tandemová hmotnostní spektrometrie MeSH
- ureasa moč MeSH
- vrozené poruchy metabolismu aminokyselin metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- enzymy imobilizované MeSH
- glutaryl-CoA-dehydrogenasa MeSH
- močovina MeSH
- ureasa MeSH
Magnetic textile solid phase extraction, based on the use of magnetically modified non-woven textile impregnated with chitosan, was successfully employed for the preconcentration of acid food dyes from water solutions. The photos of textile squares with the adsorbed dye were taken with a mobile phone. The image analysis of the photos was performed using appropriate freeware. The values of saturation, obtained through the HSB color space, were proportional to the dye concentration in the analyzed samples. Described inexpensive, simple and elution free assay enables analysis of dyes concentration in various solutions. This novel method has a potential to be a useful alternative to existing semiquantitative determination procedures, especially for dyes analysis.
- Klíčová slova
- Acid dyes, Chitosan, Image analysis, Magnetic textile solid phase extraction, Non-woven textile,
- MeSH
- adsorpce MeSH
- extrakce na pevné fázi přístrojové vybavení metody MeSH
- indigotindisulfonát sodný analýza MeSH
- magnetismus MeSH
- mobilní telefon MeSH
- počítačové zpracování obrazu MeSH
- potravinářská barviva analýza MeSH
- software MeSH
- textilie * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- indigotindisulfonát sodný MeSH
- potravinářská barviva MeSH
BACKGROUND: Physiological aggregation of a recombinant enzyme into enzymatically active inclusion bodies could be an excellent strategy to obtain immobilized enzymes for industrial biotransformation processes. However, it is not convenient to recycle "gelatinous masses" of protein inclusion bodies from one reaction cycle to another, as high centrifugation forces are needed in large volumes. The magnetization of inclusion bodies is a smart solution for large-scale applications, enabling an easier separation process using a magnetic field. RESULTS: Magnetically modified inclusion bodies of UDP-glucose pyrophosphorylase were recycled 50 times, in comparison, inclusion bodies of the same enzyme were inactivated during ten reaction cycles if they were recycled by centrifugation. Inclusion bodies of sialic acid aldolase also showed good performance and operational stability after the magnetization procedure. CONCLUSIONS: It is demonstrated here that inclusion bodies can be easily magnetically modified by magnetic iron oxide particles prepared by microwave-assisted synthesis from ferrous sulphate. The magnetic particles stabilize the repetitive use of the inclusion bodies .
The annual food and agricultural waste production reaches enormous numbers. Therefore, an increasing need to valorize produced wastes arises. Waste materials originating from the food and agricultural industry can be considered as functional materials with interesting properties and broad application potential. Moreover, using an appropriate magnetic modification, smart materials exhibiting a rapid response to an external magnetic field can be obtained. Such materials can be easily and selectively separated from desired environments. Magnetically responsive waste derivatives of biological origins have already been prepared and used as efficient biosorbents for the isolation and removal of both biologically active compounds and organic and inorganic pollutants and radionuclides, as biocompatible carriers for the immobilization of diverse types of (bio)molecules, cells, nano- and microparticles, or (bio)catalysts. Potential bactericidal, algicidal, or anti-biofilm properties of magnetic waste composites have also been tested. Furthermore, low cost and availability of waste biomaterials in larger amounts predetermine their utilization in large-scale processes.
- Klíčová slova
- agricultural and food waste, magnetic (bio)catalyst, magnetic biosorbent, magnetic carrier, magnetic modification,
- MeSH
- adsorpce MeSH
- analýza potravin * MeSH
- magnetismus metody MeSH
- odpadní produkty analýza MeSH
- recyklace metody MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- přehledy MeSH
- Názvy látek
- odpadní produkty MeSH
Cytokinins (CKs) are pivotal plant hormones that have crucial roles in plant growth and development. However, their isolation and quantification are usually challenging because of their extremely low levels in plant tissues (pmol g-1 fresh weight). We have developed a simple microscale magnetic immunoaffinity-based method for selective one-step isolation of CKs from very small amounts of plant tissue (less than 0.1 mg fresh weight). The capacity of the immunosorbent and the effect of the complex plant matrix on the yield of the rapid one-step purification were tested using a wide range of CK concentrations. The total recovery range of the new microscale isolation procedure was found to be 30-80% depending on individual CKs. Immunoaffinity extraction using group-specific monoclonal CK antibodies immobilized onto magnetic microparticles was combined with a highly sensitive ultrafast mass spectrometry-based method with a detection limit close to one attomole. This combined approach allowed metabolic profiling of a wide range of naturally occurring CKs (bases, ribosides and N9 -glucosides) in 1.0-mm sections of the Arabidopsis thaliana root meristematic zone. The magnetic immunoaffinity separation method was shown to be a simple and extremely fast procedure requiring minimal amounts of plant tissue.
- Klíčová slova
- Arabidopsis thaliana, cytokinins, immunoaffinity separation, magnetic microparticles, metabolite profiling, technical advance,
- MeSH
- Arabidopsis chemie MeSH
- cytokininy chemie izolace a purifikace MeSH
- kořeny rostlin chemie MeSH
- magnetické nanočástice * MeSH
- regulátory růstu rostlin chemie izolace a purifikace MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cytokininy MeSH
- magnetické nanočástice * MeSH
- regulátory růstu rostlin MeSH
Bacterial cellulose (BC) produced by Komagataeibacter sucrofermentans was magnetically modified using perchloric acid stabilized magnetic fluid. Magnetic bacterial cellulose (MBC) was used as a carrier for the immobilization of affinity ligands, enzymes and cells. MBC with immobilized reactive copper phthalocyanine dye was an efficient adsorbent for crystal violet removal; the maximum adsorption capacity was 388mg/g. Kinetic and thermodynamic parameters were also determined. Model biocatalysts, namely bovine pancreas trypsin and Saccharomyces cerevisiae cells were immobilized on MBC using several strategies including adsorption with subsequent cross-linking with glutaraldehyde and covalent binding on previously activated MBC using sodium periodate or 1,4-butanediol diglycidyl ether. Immobilized yeast cells retained approximately 90% of their initial activity after 6 repeated cycles of sucrose solution hydrolysis. Trypsin covalently bound after MBC periodate activation was very stable during operational stability testing; it could be repeatedly used for ten cycles of low molecular weight substrate hydrolysis without loss of its initial activity.
- Klíčová slova
- Bacterial cellulose, Copper phthalocyanine, Crystal violet, Komagataeibacter sucrofermentans, Trypsin, Yeast cells,
- MeSH
- Acetobacteraceae chemie MeSH
- bakteriální polysacharidy chemie MeSH
- celulosa chemie MeSH
- enzymy imobilizované chemie MeSH
- genciánová violeť chemie MeSH
- imobilizované buňky cytologie MeSH
- indoly chemie MeSH
- magnetismus MeSH
- nosiče léků chemie MeSH
- organokovové sloučeniny chemie MeSH
- Saccharomyces cerevisiae cytologie MeSH
- skot MeSH
- trypsin chemie MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- bakteriální polysacharidy MeSH
- celulosa MeSH
- copper phthalocyanine MeSH Prohlížeč
- enzymy imobilizované MeSH
- genciánová violeť MeSH
- indoly MeSH
- nosiče léků MeSH
- organokovové sloučeniny MeSH
- trypsin MeSH
