Microplastics can be present in the environment as manufactured microplastics (known as primary microplastics) or resulting from the continuous weathering of plastic litter, which yields ...progressively smaller plastic fragments (known as secondary microplastics). Herein, we discuss the numerous issues associated with the analysis of microplastics, and to a less extent of nanoplastics, in environmental samples (water, sediments, and biological tissues), from their sampling and sample handling to their identification and quantification. The analytical quality control and quality assurance associated with the validation of analytical methods and use of reference materials for the quantification of microplastics are also discussed, as well as the current challenges within this field of research and possible routes to overcome such limitations.
Display omitted
•Microplastics have been identified as environmental pollutants.•The sampling, sample handling, identification and quantification of microplastics were discussed.•The validation of analytical methods and use of reference materials for the microplastics quantification were highlighted.•The current challenges in these issues are identified.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The environmental monitoring has been one of the priorities at the European and global scale due to the close relationship between the environmental pollution and the human health/socioeconomic ...development. In this field, the biosensors have been widely employed as cost-effective, fast, in situ, and real-time analytical techniques. The need of portable, rapid, and smart biosensing devices explains the recent development of biosensors with new transduction materials, obtained from nanotechnology, and for multiplexed pollutant detection, involving multidisciplinary experts. This review article provides an update on recent progress in biosensors for the monitoring of air, water, and soil pollutants in real conditions such as pesticides, potentially toxic elements, and small organic molecules including toxins and endocrine disrupting chemicals.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Magnetic nanoparticles enhance sensitivity and stability of sensors and biosensors.•Magnetic nanoparticles used as labels or integrated into transducer materials.•Electrochemical and optical sensors ...and biosensors based on magnetic nanoparticles.•Piezoelectric sensors and biosensors based on magnetic nanoparticles.•Magnetic field sensors and biosensors based on magnetic nanoparticles.
Magnetic nanoparticles (MNPs) have attracted a growing interest in the development and fabrication of sensors and biosensors for several applications. MNPs can be integrated into the transducer materials and/or be dispersed in the sample followed by their attraction by an external magnetic field onto the active detection surface of the (bio)sensor. This review describes and discusses the recent applications of MNPs in sensors and biosensors, taking into consideration their analytical figures of merit. This work also addresses the future trends and perspectives of sensors and biosensors based on MNPs.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Plastic yearly production has surpassed the 300milliontons mark and recycling has all but failed in constituting a viable solution for the disposal of plastic waste. As these materials continue to ...accumulate in the environment, namely, in rivers and oceans, in the form of macro-, meso-, micro- and nanoplastics, it becomes of the utmost urgency to find new ways to curtail this environmental threat. Multiple efforts have been made to identify and isolate microorganisms capable of utilizing synthetic polymers and recent results point towards the viability of a solution for this problem based on the biodegradation of plastics resorting to selected microbial strains.
Herein, the response of the fungus Zalerion maritimum to different times of exposition to polyethylene (PE) pellets, in a minimum growth medium, was evaluated, based on the quantified mass differences in both the fungus and the microplastic pellets used. Additionally, molecular changes were assessed through attenuated total reflectance Fourier transform Infrared Spectroscopy (FTIR-ATR) and Nuclear Magnetic Resonance (NMR).
Results showed that, under the tested conditions, Z. maritimum is capable of utilizing PE, resulting in the decrease, in both mass and size, of the pellets. These results indicate that this naturally occurring fungus may actively contribute to the biodegradation of microplastics, requiring minimum nutrients.
Display omitted
•Plastic pollution is of growing concern as it accumulates in the environment.•Multiple microorganisms have been described as potential bioremediation solutions.•The potential of Zalerion maritimum in the biodegradation of polyethylene was tested.•Z. maritimum used polyethylene as evidenced by FTIR, NMR and SEM results.•The results highlight the prospective use of Z. maritimum as a bioremediation tool.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•We present the state of the art of sensors and biosensors recently used for clinical analysis.•Their analytical performance was compared, and their advantages and limitations were listed.•Methods of ...improving the analytical performance of sensors and biosensors are reported.
Sensors and biosensors have been increasingly used for clinical analysis due to their miniaturization and portability, allowing the construction of diagnostic devices for point-of-care testing. This paper presents an up-to-date overview and comparison of the analytical performance of sensors and biosensors recently used in clinical analysis. This includes cancer and cardiac biomarkers, hormones, biomolecules, neurotransmitters, bacteria, virus and cancer cells, along with related significant advances since 2011. Some methods of enhancing the analytical performance of sensors and biosensors through their figures of merit are also discussed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The olive oil mill wastewater (OMW) is a problematic and polluting effluent which may degrade the soil and water quality, with critical negative impacts on ecosystems functions and services provided. ...The main purpose of this review paper is presenting the state of the art of OMW treatments focusing on their efficiency to reduce OMW toxicity, and emphasizing the role of ecotoxicological tests on the evaluation of such efficiency before the up-scale of treatment methodologies being considered. In the majority of research works, the reduction of OMW toxicity is related to the degradation of phenolic compounds (considered as the main responsible for the toxic effects of OMW on seed germination, on bacteria, and on different species of soil and aquatic invertebrates) or the decrease of chemical oxygen demand content, which is not scientifically sound. Batteries of ecotoxicological tests are not applied before and after OMW treatments as they should be, thus leading to knowledge gaps in terms of accurate and real assessment of OMW toxicity. Although the toxicity of OMW is usually high, the evaluation of effects on sub-lethal endpoints, on individual and multispecies test systems, are currently lacking, and the real impacts yielded by its dilution, in freshwater trophic chains of receiving systems can not be assessed. As far as the terrestrial compartment is considered, ecotoxicological data available include tests only with plants and the evaluation of soil microbial parameters, reflecting concerns with the impacts on crops when using OMW for irrigation purposes. The evaluation of its ecotoxicity to other edaphic species were not performed giving rise to a completely lack of knowledge about the consequences of such practice on other soil functions. OMW production is a great environmental problem in Mediterranean countries; hence, engineers, chemists and ecotoxicologists should face this problem together to find an ecologically friend solution.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
7.
Graphene based sensors and biosensors Justino, Celine I.L.; Gomes, Ana R.; Freitas, Ana C. ...
TrAC, Trends in analytical chemistry (Regular ed.),
June 2017, 2017-06-00, Volume:
91
Journal Article
Peer reviewed
Graphene has contributed to the fabrication of sensitive sensors and biosensors due to its physical and electrochemical properties. This review discusses the role of graphene and graphene related ...materials for the improvement of the analytical performance of sensors and biosensors. This paper also provides an overview of recent graphene based sensors and biosensors (2012–2016), comparing their analytical performance for application in clinical, environmental, and food sciences research, and comments on future and interesting research trends in this field.
•We overview the recent sensors and biosensors based on graphene and graphene related materials.•Their analytical performance was compared according to the clinical, environmental, and food applications.•We discuss the role of graphene and graphene related materials for the improvement of their analytical performance.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Seaweeds are an excellent source of bioactive compounds, and therefore the use of sustainable and food compatible extraction methods such as enzyme-assisted (EAE) and ultrasound-assisted extraction ...were applied on Sargassum muticum, Osmundea pinnatifida, and Codium tomentosum. Extracts were evaluated for proximate characterization and biological properties. Higher extraction yields were observed for C. tomentosum EAE (48–62%; p < 0.05 for Cellulase and Viscozyme), followed by O. pinnatifida (49–55%; p < 0.05 except Alcalase) and S. muticum (26–31%; p < 0.05). S. muticum extracts presented the highest nitrogen (25 ± 2 mg/glyoph extract) and total phenolics (261 ± 37 μgcatechol equiv/glyoph extract) contents, whereas higher sugars (78 ± 14 mgglucose equiv/glyoph extract) including sulfated polysaccharide (44 ± 8 mgNa2SO4 acid/glyoph extract) contents characterized O. pinnatifida extracts. A higher effect on hydroxyl-radical scavenging activity (35–50%) was observed for all extracts, whereas S. muticum Alcalase and C. tomentosum Cellulase extracts exhibited higher prebiotic activity than fructooligosaccharides. O. pinnatifida and C. tomentosum EAE showed inhibitory potential against α-glucosidase (38–49%).
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM, UPUK
9.
Supercritical fluid extraction of bioactive compounds da Silva, Rui P.F.F.; Rocha-Santos, Teresa A.P.; Duarte, Armando C.
TrAC, Trends in analytical chemistry (Regular ed.),
February 2016, 2016-02-00, 2016-02-01, Volume:
76, Issue:
C
Journal Article
Peer reviewed
Open access
•SFE as a green alternative to conventional extraction of bioactive compounds.•Techniques and methodologies for SFE improvement.•Experimental design for optimization of SFE operational ...conditions.•Structural characterization of bioactive compounds obtained by SFE.
An ideal extraction method should be swift, yield quantitative recovery without degradation, and the extracts should be easily separated from the solvent. The development and application of alternative green technology to replace conventional extraction methods with improved extraction efficiency and low environmental impact for the determination of natural bioactive compounds is therefore, highly important. Supercritical fluid technology offers features that overcome many limitations of conventional extraction methods.
This review presents an analytical overview regarding the application of supercritical fluids in the extraction of bioactive compounds and their operative extraction conditions, along with the investigation of further improvements on the extraction efficiency and the applied techniques for the structural characterization and identification of such bioactive compounds.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Chemical composition of six red, brown and green seaweeds from Portuguese Coast is given.•Inter and intra class seaweed variations were observed in nutritional quality.•Seaweeds contained low fat ...but a specific FA profile rich in EPA and phytanic acid.•Some of the seaweed species may be seen as good sources of Ca, K, Mg and Fe.•FTIR-ATR and FT-Raman enabled polysaccharides characterization in each seaweed class.
Six representative edible seaweeds from the Central West Portuguese Coast, including the less studied Osmundea pinnatifida, were harvested from Buarcos bay, Portugal and their chemical characterization determined. Protein content, total sugar and fat contents ranged between 14.4% and 23.8%, 32.4% and 49.3% and 0.6–3.6%. Highest total phenolic content was observed in Codium tomentosum followed by Sargassum muticum and O. pinnatifida. Fatty acid (FA) composition covered the branched chain C13ai to C22:5 n3 with variable content in n6 and n3 FA; low n6:n3 ratios were observed in O. pinnatifida, Grateloupia turuturu and C. tomentosum. Some seaweed species may be seen as good sources of Ca, K, Mg and Fe, corroborating their good nutritional value. According to FTIR-ATR spectra, G. turuturu was associated with carrageenan seaweed producers whereas Gracilaria gracilis and O. pinnatifida were mostly agar producers. In the brown algae, S. muticum and Saccorhiza polyschides, alginates and fucoidans were the main polysaccharides found.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PDF
