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A sol-gel thiocyanatopropyl-functionalized silica sorbent was synthesized and employed for an automated on-line microcolumn preconcentration platform as a front-end to inductively coupled plasma atomic emission spectroscopy (ICP-AES) for the simultaneous determination of Cd(II), Pb(II), Cu(II), Cr(III), Co(II), Ni(II), Zn(II), Mn(II), Hg(II), and V(II). The developed system is based on an easy-to-repack microcolumn construction integrated into a flow injection manifold coupled directly to ICP-AES’s nebulizer. After on-line extraction/preconcentration of the target analyte onto the surface of the sorbent, successive elution with 1.0 mol L−1 HNO3 was performed. All main chemical and hydrodynamic factors affecting the effectiveness of the system were thoroughly investigated and optimized. Under optimized experimental conditions, for 60 s preconcentration time, the enhancement factor achieved for the target analytes was between 31 to 53. The limits of detection varied in the range of 0.05 to 0.24 μg L−1, while the limits of quantification ranged from 0.17 to 0.79 μg L−1. The precision of the method was expressed in terms of relative standard deviation (RSD%) and was less than 7.9%. Furthermore, good method accuracy was observed by analyzing three certified reference materials. The proposed method was also successfully employed for the analysis of environmental water samples.
Natalia Manousi; Abuzar Kabir; Kenneth Furton; George Zachariadis; Aristidis Anthemidis. Multi-Element Analysis Based on an Automated On-Line Microcolumn Separation/Preconcentration System Using a Novel Sol-Gel Thiocyanatopropyl-Functionalized Silica Sorbent Prior to ICP-AES for Environmental Water Samples. Molecules 2021, 26, 4461 .
AMA StyleNatalia Manousi, Abuzar Kabir, Kenneth Furton, George Zachariadis, Aristidis Anthemidis. Multi-Element Analysis Based on an Automated On-Line Microcolumn Separation/Preconcentration System Using a Novel Sol-Gel Thiocyanatopropyl-Functionalized Silica Sorbent Prior to ICP-AES for Environmental Water Samples. Molecules. 2021; 26 (15):4461.
Chicago/Turabian StyleNatalia Manousi; Abuzar Kabir; Kenneth Furton; George Zachariadis; Aristidis Anthemidis. 2021. "Multi-Element Analysis Based on an Automated On-Line Microcolumn Separation/Preconcentration System Using a Novel Sol-Gel Thiocyanatopropyl-Functionalized Silica Sorbent Prior to ICP-AES for Environmental Water Samples." Molecules 26, no. 15: 4461.
In this study a simple and sensitive on-line sorbent extraction platform coupled with flame atomic absorption spectrometry for trace metals determination was developed. The system utilized for the first time a novel sol-gel thiocyanatopropyl functionalized silica as adsorbent for metal’s separation and preconcentration. The main factors affecting the performance of the on-line system were investigated and optimized. The effect of potential interfering species that occur naturally in environmental and biological samples, as well as some toxic elements, was evaluated. Under optimum conditions the enhancement factors ranged between 73 and 152 for the target analytes. The LODs of the proposed methods were 0.15 μg L−1 for Cd(II), 0.5 μg L−1 for Co(II), 0.5 μg L−1 for Cu(II) and 1.9 μg L−1 for Pb(II) for 120 s preconcentration time. The relative standard deviation values for all elements were less than 3.8%, indicating good method precision. Moreover, the sol-gel thiocyanatopropyl functionalized silica-packed microcolumns exhibited limited flow resistance and excellent packing reproducibility. Finally, the proposed method was utilized for the analysis of environmental and biological samples.
Natalia Manousi; Abuzar Kabir; Kenneth Furton; George Zachariadis; Aristidis Anthemidis. Automated Solid Phase Extraction of Cd(II), Co(II), Cu(II) and Pb(II) Coupled with Flame Atomic Absorption Spectrometry Utilizing a New Sol-Gel Functionalized Silica Sorbent. Separations 2021, 8, 100 .
AMA StyleNatalia Manousi, Abuzar Kabir, Kenneth Furton, George Zachariadis, Aristidis Anthemidis. Automated Solid Phase Extraction of Cd(II), Co(II), Cu(II) and Pb(II) Coupled with Flame Atomic Absorption Spectrometry Utilizing a New Sol-Gel Functionalized Silica Sorbent. Separations. 2021; 8 (7):100.
Chicago/Turabian StyleNatalia Manousi; Abuzar Kabir; Kenneth Furton; George Zachariadis; Aristidis Anthemidis. 2021. "Automated Solid Phase Extraction of Cd(II), Co(II), Cu(II) and Pb(II) Coupled with Flame Atomic Absorption Spectrometry Utilizing a New Sol-Gel Functionalized Silica Sorbent." Separations 8, no. 7: 100.
In recent years, there has been an increase in public perception of the detrimental side-effects of fluoride to human health due to its effects on teeth and bones. Today, there is a plethora of techniques available for the removal of fluoride from drinking water. Among them, adsorption is a very prospective method because of its handy operation, cost efficiency, and high selectivity. Along with efforts to assist fluoride removal from drinking waters, extensive attention has been also paid to the accurate measurement of fluoride in water. Currently, the analytical methods that are used for fluoride determination can be classified into chromatographic methods (e.g., ionic chromatography), electrochemical methods (e.g., voltammetry, potentiometry, and polarography), spectroscopic methods (e.g., molecular absorption spectrometry), microfluidic analysis (e.g., flow injection analysis and sequential injection analysis), titration, and sensors. In this review article, we discuss the available techniques and the ongoing effort for achieving enhanced fluoride removal by applying novel adsorbents such as carbon-based materials (i.e., activated carbon, graphene oxide, and carbon nanotubes) and nanostructured materials, combining metals and their oxides or hydroxides as well as natural materials. Emphasis has been given to the use of lanthanum (La) in the modification of materials, both activated carbon and hybrid materials (i.e., La/Mg/Si-AC, La/MA, LaFeO3 NPs), and in the use of MgO nanostructures, which are found to exhibit an adsorption capacity of up to 29,131 mg g−1. The existing analytical methodologies and the current trends in analytical chemistry for fluoride determination in drinking water are also discussed.
Athanasia Tolkou; Natalia Manousi; George Zachariadis; Ioannis Katsoyiannis; Eleni Deliyanni. Recently Developed Adsorbing Materials for Fluoride Removal from Water and Fluoride Analytical Determination Techniques: A Review. Sustainability 2021, 13, 7061 .
AMA StyleAthanasia Tolkou, Natalia Manousi, George Zachariadis, Ioannis Katsoyiannis, Eleni Deliyanni. Recently Developed Adsorbing Materials for Fluoride Removal from Water and Fluoride Analytical Determination Techniques: A Review. Sustainability. 2021; 13 (13):7061.
Chicago/Turabian StyleAthanasia Tolkou; Natalia Manousi; George Zachariadis; Ioannis Katsoyiannis; Eleni Deliyanni. 2021. "Recently Developed Adsorbing Materials for Fluoride Removal from Water and Fluoride Analytical Determination Techniques: A Review." Sustainability 13, no. 13: 7061.
A novel magnetic solid phase material based on a micro–meso porous activated carbon/Fe3O4 nanocomposite was used to extract caffeine from surface water samples. The method is efficient and rapid, and has minimum solvent consumption.
Natalia Manousi; Eleni A. Deliyanni; Erwin Rosenberg; George A. Zachariadis. Magnetic solid-phase extraction of caffeine from surface water samples with a micro–meso porous activated carbon/Fe3O4 nanocomposite prior to its determination by GC-MS. RSC Advances 2021, 11, 19492 -19499.
AMA StyleNatalia Manousi, Eleni A. Deliyanni, Erwin Rosenberg, George A. Zachariadis. Magnetic solid-phase extraction of caffeine from surface water samples with a micro–meso porous activated carbon/Fe3O4 nanocomposite prior to its determination by GC-MS. RSC Advances. 2021; 11 (32):19492-19499.
Chicago/Turabian StyleNatalia Manousi; Eleni A. Deliyanni; Erwin Rosenberg; George A. Zachariadis. 2021. "Magnetic solid-phase extraction of caffeine from surface water samples with a micro–meso porous activated carbon/Fe3O4 nanocomposite prior to its determination by GC-MS." RSC Advances 11, no. 32: 19492-19499.
Bioanalysis is the scientific field of the quantitative determination of xenobiotics (e.g., drugs and their metabolites) and biotics (e.g., macromolecules) in biological matrices. The most common samples in bioanalysis include blood (i.e., serum, plasma and whole blood) and urine. However, the analysis of alternative biosamples, such as hair and nails are gaining more and more attention. The main limitations for the determination of small organic compounds in biological samples is their low concentration in these matrices, in combination with the sample complexity. Therefore, a sample preparation/analyte preconcentration step is typically required. Currently, the development of novel microextraction and miniaturized extraction techniques, as well as novel adsorbents for the analysis of biosamples, in compliance with the requirements of Green Analytical Chemistry, is in the forefront of research in analytical chemistry. Graphene oxide (GO) is undoubtedly a powerful adsorbent for sample preparation that has been successfully coupled with a plethora of green extraction techniques. GO is composed of carbon atoms in a sp2 single-atom layer of a hybrid connection, and it exhibits high surface area, as well as good mechanical and thermal stability. In this review, we aim to discuss the applications of GO and functionalized GO derivatives in microextraction and miniaturized extraction techniques for the determination of small organic molecules in biological samples.
Natalia Manousi; Orfeas-Evangelos Plastiras; Eleni Deliyanni; George Zachariadis. Green Bioanalytical Applications of Graphene Oxide for the Extraction of Small Organic Molecules. Molecules 2021, 26, 2790 .
AMA StyleNatalia Manousi, Orfeas-Evangelos Plastiras, Eleni Deliyanni, George Zachariadis. Green Bioanalytical Applications of Graphene Oxide for the Extraction of Small Organic Molecules. Molecules. 2021; 26 (9):2790.
Chicago/Turabian StyleNatalia Manousi; Orfeas-Evangelos Plastiras; Eleni Deliyanni; George Zachariadis. 2021. "Green Bioanalytical Applications of Graphene Oxide for the Extraction of Small Organic Molecules." Molecules 26, no. 9: 2790.
The quantitative determination of xenobiotic compounds, as well as biotics in biological matrices, is generally described with the term bioanalysis. Due to the complexity of biofluids, in combination with the low concentration of the small molecules, their determination in biological matrices is a challenging procedure. Apart from the conventional solid-phase extraction, liquid-liquid extraction, protein precipitation, and direct injection approaches, nowadays, a plethora of microextraction and miniaturized extraction techniques have been reported. Furthermore, the development and evaluation of novel extraction adsorbents for sample preparation has become a popular research field. Metal-organic frameworks (MOFs) are novel materials composed of metal ions or clusters in coordination with organic linkers. Unequivocally, MOFs are gaining more and more attention in analytical chemistry due to their superior properties, including high surface area and tunability of pore size and functionality. This review discusses the utilization of MOFs in the sample preparation of biological samples for the green extraction of small organic molecules. Their common preparation and characterization strategies are discussed, while emphasis is given to their applications for green sample preparation.
Natalia Manousi; Orfeas-Evangelos Plastiras; Natasa Kalogiouri; Constantinos Zacharis; George Zachariadis. Metal-Organic Frameworks in Bioanalysis: Extraction of Small Organic Molecules. Separations 2021, 8, 60 .
AMA StyleNatalia Manousi, Orfeas-Evangelos Plastiras, Natasa Kalogiouri, Constantinos Zacharis, George Zachariadis. Metal-Organic Frameworks in Bioanalysis: Extraction of Small Organic Molecules. Separations. 2021; 8 (5):60.
Chicago/Turabian StyleNatalia Manousi; Orfeas-Evangelos Plastiras; Natasa Kalogiouri; Constantinos Zacharis; George Zachariadis. 2021. "Metal-Organic Frameworks in Bioanalysis: Extraction of Small Organic Molecules." Separations 8, no. 5: 60.
Fabric phase sorptive extraction (FPSE) is a recently introduced sample preparation technique that has attracted substantial interest of the scientific community dealing with bioanalysis. This technique is based on a permeable and flexible substrate made of fabric, coated with a sol-gel organic-inorganic sorbent. Among the benefits of FPSE are its tunable selectivity, adjustable porosity, minimized sample preparation workflow, substantially reduced organic solvent consumption, rapid extraction kinetics and superior extraction efficiency, many of which are well-known criteria for Green Analytical Chemistry. As such, FPSE has established itself as a leading green sample preparation technology of 21st century. In this review, we discuss the principal steps for the development of an FPSE method, the main method optimization strategies, as well as the applications of FPSE in bioanalysis for the extraction of a wide range of analytes (e.g., estrogens, benzodiazepines, androgens and progestogens, penicillins, anti-inflammatory drugs, parabens etc.).
Natalia Manousi; Abuzar Kabir; George A Zachariadis. Green bioanalytical sample preparation: fabric phase sorptive extraction. Bioanalysis 2021, 13, 693 -710.
AMA StyleNatalia Manousi, Abuzar Kabir, George A Zachariadis. Green bioanalytical sample preparation: fabric phase sorptive extraction. Bioanalysis. 2021; 13 (9):693-710.
Chicago/Turabian StyleNatalia Manousi; Abuzar Kabir; George A Zachariadis. 2021. "Green bioanalytical sample preparation: fabric phase sorptive extraction." Bioanalysis 13, no. 9: 693-710.
The trace element content of thirty-two nuts including almonds, walnuts, hazelnuts and pistachios available in a Greek market was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Wet acid digestion using nitric acid (65%) took place in Teflon autoclaves. The limits of detection (LODs) and limits of quantification (LOQs) ranged between 0.01 (Mg)–2.52 (Cu) μg g−1 and 0.02 (Mg)–8.40 (Cu) μg g−1, respectively. Good method linearity (r2 > 0.9990) was observed for each element at the selected emission lines. The metals were quantified and one-way analysis of variance (ANOVA) was used to examine whether or not there were any statistically significant differences among the metal concentrations inside the different nut species.
Natasa Kalogiouri; Natalia Manousi; George Zachariadis. Determination of the Toxic and Nutrient Element Content of Almonds, Walnuts, Hazelnuts and Pistachios by ICP-AES. Separations 2021, 8, 28 .
AMA StyleNatasa Kalogiouri, Natalia Manousi, George Zachariadis. Determination of the Toxic and Nutrient Element Content of Almonds, Walnuts, Hazelnuts and Pistachios by ICP-AES. Separations. 2021; 8 (3):28.
Chicago/Turabian StyleNatasa Kalogiouri; Natalia Manousi; George Zachariadis. 2021. "Determination of the Toxic and Nutrient Element Content of Almonds, Walnuts, Hazelnuts and Pistachios by ICP-AES." Separations 8, no. 3: 28.
Pistachios are a nutritionally beneficial food source widely consumed all over the world. Pistachios exhibit high content of antioxidants, vitamins and other beneficial micronutrients, including nutrient elements and rare earth elements (REEs). Considering that the concentration of REEs depends on the climate and soil characteristics that vary among different geographical regions, REEs could constitute markers responsible for the geographical discrimination of this nut type. In this study, Greek pistachios with a protected designation of origin (PDO) label from Aegina Island and Fthiotida and Turkish pistachios from Adana were analyzed with inductively coupled plasma mass spectrometry (ICP-MS) to assess their REE profile. La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb were determined and quantified. The quantification results were further analyzed using the main effect plot, permutational analysis of variance (PERMANOVA), nonmetric multidimensional scaling (nMDS), principal component analysis (PCA) and hierarchical clustering (HCA) to investigate the similarities between the pistachios. A decision tree (DT) was developed for the classification of pistachios according to their geographical origin proving to be a promising and reliable tool for verifying the authenticity of food products on the basis of their REE profile.
Natasa Kalogiouri; Natalia Manousi; Dimitris Klaoudatos; Thomas Spanos; Vilson Topi; George Zachariadis. Rare Earths as Authenticity Markers for the Discrimination of Greek and Turkish Pistachios Using Elemental Metabolomics and Chemometrics. Foods 2021, 10, 349 .
AMA StyleNatasa Kalogiouri, Natalia Manousi, Dimitris Klaoudatos, Thomas Spanos, Vilson Topi, George Zachariadis. Rare Earths as Authenticity Markers for the Discrimination of Greek and Turkish Pistachios Using Elemental Metabolomics and Chemometrics. Foods. 2021; 10 (2):349.
Chicago/Turabian StyleNatasa Kalogiouri; Natalia Manousi; Dimitris Klaoudatos; Thomas Spanos; Vilson Topi; George Zachariadis. 2021. "Rare Earths as Authenticity Markers for the Discrimination of Greek and Turkish Pistachios Using Elemental Metabolomics and Chemometrics." Foods 10, no. 2: 349.
Plant-based drinks are non-dairy milk alternative beverages that are nowadays widely consumed across the world. Among them, nut-based milk alternative beverages such as almond drink, walnut drink, and peanut drink are gaining more and more popularity. This study presents the development and validation of an inductively coupled plasma–optical emission spectrometry (ICP-OES) method for the determination of nutrient and toxic metals elements in nut-based drinks. The determined metals were Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, In, Mg, Mn, Ni, Pb, and Zn. The mineralization process of drink samples was optimized in order to achieve complete dissolution. Under optimized conditions, mineralization of 2 g of the nut-based drinks was achieved by the addition of 3 mL of nitric acid and heating at 120°C for 60 min into Teflon autoclaves. The proposed method was validated in terms of linearity, accuracy, precision, limits of detection (LODs), and limits of quantification (LOQs). The relative standard deviations (RSD%) for all elements were 0.4–10.8%, and the relative recovery values (RR%) were 90.0–109.7%, demonstrating that the method offered good precision and accuracy. The LODs for the determined elements were found to be 0.03–1.08 mg kg−1, while the LOQs were found to be 0.10–3.23 mg kg−1. The developed method was successfully employed for the analysis of different commercial nut-based drinks (e.g., almond-based drinks, walnut-based drinks, peanut-based drinks etc.) obtained from the local market.
N. Manousi; G. A. Zachariadis. A Simple and Rapid Analytical Method for the Determination of Nutrient and Toxic Elements in Nut-Based Milk Alternative Beverages by ICP-OES. Food Analytical Methods 2021, 14, 1315 -1321.
AMA StyleN. Manousi, G. A. Zachariadis. A Simple and Rapid Analytical Method for the Determination of Nutrient and Toxic Elements in Nut-Based Milk Alternative Beverages by ICP-OES. Food Analytical Methods. 2021; 14 (7):1315-1321.
Chicago/Turabian StyleN. Manousi; G. A. Zachariadis. 2021. "A Simple and Rapid Analytical Method for the Determination of Nutrient and Toxic Elements in Nut-Based Milk Alternative Beverages by ICP-OES." Food Analytical Methods 14, no. 7: 1315-1321.
A novel sample preparation method based on the use of the Arrow solid-phase microextraction device was used to extract and preconcentrate volatile organic compounds (VOCs) from milk samples prior to their determination by gas chromatography–mass spectrometry (GC-MS). The experimental parameters of the solid-phase microextraction (SPME) Arrow method were evaluated in terms of fiber type, sample volume, extraction temperature, extraction time, stirring rate and salt addition. Under the optimum extraction conditions, the SPME Arrow was compared with conventional SPME fibers to evaluate the effectiveness of the SPME Arrow method. Evaluation of the conventional SPME procedure was also performed under optimized conditions, for appropriate method comparison. Due to the larger sorption phase volume of SPME Arrow, a higher sensitivity and reproducibility were observed for the determined chromatographic peaks in comparison with conventional SPME fibers. The use of Carbon wide range (WR) SPME Arrow/polydimethylsiloxane (CAR/PDMS) SPME Arrow fibers leads to a compound-dependent improvement of a factor of 4–5x over the classical SPME setup. Moreover, the relative standard deviation (RSD) of the total volatiles for a conventional SPME procedure was 12.5%, while for SPME Arrow it was 6.2%. Finally, the novel method was successfully employed for the analysis of commercially available milk samples. The findings of this study indicate that SPME Arrow can be effectively used for the determination of volatile organic compounds in complex food matrixes.
Natalia Manousi; Erwin Rosenberg; George A. Zachariadis. Solid-Phase Microextraction Arrow for the Sampling of Volatile Organic Compounds in Milk Samples. Separations 2020, 7, 75 .
AMA StyleNatalia Manousi, Erwin Rosenberg, George A. Zachariadis. Solid-Phase Microextraction Arrow for the Sampling of Volatile Organic Compounds in Milk Samples. Separations. 2020; 7 (4):75.
Chicago/Turabian StyleNatalia Manousi; Erwin Rosenberg; George A. Zachariadis. 2020. "Solid-Phase Microextraction Arrow for the Sampling of Volatile Organic Compounds in Milk Samples." Separations 7, no. 4: 75.
This study presents the determination of toxic and nutrient elements in vinegar samples using inductively coupled plasma – atomic emission spectrometry (ICP-AES). The determined elements were Pb, Ni, Cr, Cu, Mg, Zn, Fe, Al, Ba, Ca, Co, and Cd. The aim of this study was to develop a simple and rapid method for the elemental analysis of vinegar samples without sample dilution that can result in sensitivity loss and without acidic digestion that could significantly increase the time and complexity of the overall process. Therefore, direct analysis of vinegars was employed and parameters including the radiofrequency power and the sample uptake were evaluated, in order to have stable plasma conditions. Under the optimum conditions, vinegar samples with a maximum concentration of 6% v/v were analyzed using a radiofrequency power of 1350 W and a sample uptake of 1.5 L min−1. The proposed method was validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision. The LODs were between 0.1 and 22.1 μg L−1, while the LOQs were between 0.3 and 73.0 μg L−1 for the examined trace elements. The developed method was successfully employed for the analysis of 10 different commercially available vinegar samples that included white grape vinegar, red wine vinegar, apple cider vinegar, and balsamic vinegar.
Ioanna P. Paktsevanidou; N. Manousi; G. A. Zachariadis. Development and Validation of an Inductively Coupled Plasma – Atomic Emission Spectrometry (ICP-AES) Method for Trace Element Determination in Vinegar. Analytical Letters 2020, 54, 2227 -2238.
AMA StyleIoanna P. Paktsevanidou, N. Manousi, G. A. Zachariadis. Development and Validation of an Inductively Coupled Plasma – Atomic Emission Spectrometry (ICP-AES) Method for Trace Element Determination in Vinegar. Analytical Letters. 2020; 54 (13):2227-2238.
Chicago/Turabian StyleIoanna P. Paktsevanidou; N. Manousi; G. A. Zachariadis. 2020. "Development and Validation of an Inductively Coupled Plasma – Atomic Emission Spectrometry (ICP-AES) Method for Trace Element Determination in Vinegar." Analytical Letters 54, no. 13: 2227-2238.
A novel graphene-oxide-derived material was synthesized after modification of graphene oxide with sodium hydroxide and used for the dispersive solid-phase extraction (d-SPE) of different elements (Pb, Cd, Ba, Zn, Cu and Ni) prior to their determination by inductively coupled plasma atomic emission spectrometry (ICP-AES). The prepared nanomaterial was characterized by X-ray diffraction (XRD), nitrogen adsorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. Full factorial design and Derringer’s type desirability function were used for the optimization of the d-SPE procedure. Pareto charts illustrated the effects of each of the examined factors and their interactions on the determination of the elements. Under the optimum conditions, detection limits (LODs) for the elements ranged between 0.01 and 0.21 μg g−1, intra-day repeatability (n = 5) was lower than 1.9% and inter-day repeatability (n = 5 × 3) was lower than 4.7%. Relative recovery values ranged between 88.1 and 117.8%. The method was validated and successfully applied for the determination of trace elements in poultry, pork and beef samples from the local market. The proposed method is simple, rapid, sensitive and the novel sorbent can be used at least ten times.
Natalia Manousi; Eleni Deliyanni; George Zachariadis. Multi-Element Determination of Toxic and Nutrient Elements by ICP-AES after Dispersive Solid-Phase Extraction with Modified Graphene Oxide. Applied Sciences 2020, 10, 8722 .
AMA StyleNatalia Manousi, Eleni Deliyanni, George Zachariadis. Multi-Element Determination of Toxic and Nutrient Elements by ICP-AES after Dispersive Solid-Phase Extraction with Modified Graphene Oxide. Applied Sciences. 2020; 10 (23):8722.
Chicago/Turabian StyleNatalia Manousi; Eleni Deliyanni; George Zachariadis. 2020. "Multi-Element Determination of Toxic and Nutrient Elements by ICP-AES after Dispersive Solid-Phase Extraction with Modified Graphene Oxide." Applied Sciences 10, no. 23: 8722.
In this study, a method for the determination of trace elements in snacks using inductively coupled plasma–atomic emission spectrometry (ICP-AES) is presented. The examined elements were Pb, Ni, Cr, Cu, Mg, Zn, Fe, Al, Ba, Ca, Co, Mn and Cd. Under the optimized conditions, digestion of 300 mg of the snack samples was performed by the addition of 5 mL of nitric acid in a Teflon autoclave and by heating the obtained mixture at 120 °C for 75 min. In order to evaluate the efficiency of the proposed protocol, method linearity, accuracy precision, limits of detection (LODs) and limits of quantification (LOQs) were evaluated. The relative standard deviations (RSD%) for all elements were lower than 13.5%, demonstrating that the method offered good precision. The relative recoveries values (R%) ranged between 80–120%, demonstrating that the method offered good accuracy. The LODs for all the trace elements ranged between 0.18 and 3.75 μg g−1, while the LOQs ranged between 0.60 and 12.50 μg g−1. Finally, the proposed protocol was implemented for the analysis of a wide variety of savory snack samples including commercial snacks from corn, potato chips, popcorns, puffed rice cake and crackers.
Natalia Manousi; George A. Zachariadis. Development and Application of an ICP-AES Method for the Determination of Nutrient and Toxic Elements in Savory Snack Products after Autoclave Dissolution. Separations 2020, 7, 66 .
AMA StyleNatalia Manousi, George A. Zachariadis. Development and Application of an ICP-AES Method for the Determination of Nutrient and Toxic Elements in Savory Snack Products after Autoclave Dissolution. Separations. 2020; 7 (4):66.
Chicago/Turabian StyleNatalia Manousi; George A. Zachariadis. 2020. "Development and Application of an ICP-AES Method for the Determination of Nutrient and Toxic Elements in Savory Snack Products after Autoclave Dissolution." Separations 7, no. 4: 66.
Graphene oxide is a compound with a form similar to graphene, composed of carbon atoms in a sp2 single-atom layer of a hybrid connection. Due to its significant surface area and its good mechanical and thermal stability, graphene oxide has a plethora of applications in various scientific fields including heterogenous catalysis, gas storage, environmental remediation, etc. In analytical chemistry, graphene oxide has been successfully employed for the extraction and preconcentration of organic compounds, metal ions, and proteins. Since graphene oxide sheets are negatively charged in aqueous solutions, the material and its derivatives are ideal sorbents to bind with metal ions. To date, various graphene oxide nanocomposites have been successfully synthesized and evaluated for the extraction and preconcentration of metal ions from biological, environmental, agricultural, and food samples. In this review article, we aim to discuss the application of graphene oxide and functionalized graphene oxide nanocomposites for the extraction of metal ions prior to their determination via an instrumental analytical technique. Applications of ionic liquids and deep eutectic solvents for the modification of graphene oxide and its functionalized derivatives are also discussed.
Natalia Manousi; Erwin Rosenberg; Eleni A. Deliyanni; George A. Zachariadis. Sample Preparation Using Graphene-Oxide-Derived Nanomaterials for the Extraction of Metals. Molecules 2020, 25, 2411 .
AMA StyleNatalia Manousi, Erwin Rosenberg, Eleni A. Deliyanni, George A. Zachariadis. Sample Preparation Using Graphene-Oxide-Derived Nanomaterials for the Extraction of Metals. Molecules. 2020; 25 (10):2411.
Chicago/Turabian StyleNatalia Manousi; Erwin Rosenberg; Eleni A. Deliyanni; George A. Zachariadis. 2020. "Sample Preparation Using Graphene-Oxide-Derived Nanomaterials for the Extraction of Metals." Molecules 25, no. 10: 2411.
Polycyclic aromatic hydrocarbons (PAHs) comprise a group of chemical compounds consisting of two or more fused benzene rings. PAHs exhibit hydrophobicity and low water solubility, while some of their members are toxic substances resistant to degradation. Due to their low levels in environmental matrices, a preconcentration step is usually required for their determination. Nowadays, there is a wide variety of sample preparation techniques, including micro-extraction techniques (e.g., solid-phase microextraction and liquid phase microextraction) and miniaturized extraction techniques (e.g., dispersive solid-phase extraction, magnetic solid-phase extraction, stir bar sorptive extraction, fabric phase sorptive extraction etc.). Compared to the conventional sample preparation techniques, these novel techniques show some benefits, including reduced organic solvent consumption, while they are time and cost efficient. A plethora of adsorbents, such as metal-organic frameworks, carbon-based materials and molecularly imprinted polymers, have been successfully coupled with a wide variety of extraction techniques. This review focuses on the recent advances in the extraction techniques of PAHs from environmental matrices, utilizing novel sample preparation approaches and adsorbents.
Natalia Manousi; George A. Zachariadis. Recent Advances in the Extraction of Polycyclic Aromatic Hydrocarbons from Environmental Samples. Molecules 2020, 25, 2182 .
AMA StyleNatalia Manousi, George A. Zachariadis. Recent Advances in the Extraction of Polycyclic Aromatic Hydrocarbons from Environmental Samples. Molecules. 2020; 25 (9):2182.
Chicago/Turabian StyleNatalia Manousi; George A. Zachariadis. 2020. "Recent Advances in the Extraction of Polycyclic Aromatic Hydrocarbons from Environmental Samples." Molecules 25, no. 9: 2182.
The nature of the surface is critical in determining the biological activity of silica powders. A novel correlation between toxicity and surface properties of bioactive glass ceramics (BGCs) synthesized via the sol–gel method was attempted in this study. The behavior of BGCs after their attachment to the surface of red blood cells (RBCs) was evaluated and their toxic effects were determined based on hemolysis, membrane injury via anti-phosphotyrosine immunoblot of Band 3, lipid peroxidation, potential to generate reactive oxygen species, and antioxidant enzyme production. In particular, three BGCs were synthesized and treated at three sintering temperatures (T1 = 835 °C, T2 = 1000 °C and T3 = 1100 °C) to investigate possible relation between surface charge or structure and hemolytic potential. Their toxicity based on hemolysis was dose dependent, while BGC-T2 had the best hemocompatibility in compare with the other BGCs.No BGCs in dosages lower than 0.125 mg/mL could damage erythrocytes. On the other hand, all BGCs promoted the production of reactive oxygen species in certain concentrations, with the BGC-T2 producing the lowest ROS and increasing the glutathione levels in RBCs protecting their damage. The results suggest that various factors such as size, a probable different proportion of surface silanols, a balanced mechanism between calcium and magnesium cellular uptake or the different crystalline nature may have contributed to this finding; however, future research is needed to clarify the underlying mechanisms.
Ioannis Tsamesidis; Konstantina Kazeli; Evgenia Lymperaki; Georgia K. Pouroutzidou; Ilias M. Oikonomou; Philomela Komninou; George Zachariadis; Karine Reybier; Antonella Pantaleo; Eleana Kontonasaki. Effect of Sintering Temperature of Bioactive Glass Nanoceramics on the Hemolytic Activity and Oxidative Stress Biomarkers in Erythrocytes. Cellular and Molecular Bioengineering 2020, 13, 201 -218.
AMA StyleIoannis Tsamesidis, Konstantina Kazeli, Evgenia Lymperaki, Georgia K. Pouroutzidou, Ilias M. Oikonomou, Philomela Komninou, George Zachariadis, Karine Reybier, Antonella Pantaleo, Eleana Kontonasaki. Effect of Sintering Temperature of Bioactive Glass Nanoceramics on the Hemolytic Activity and Oxidative Stress Biomarkers in Erythrocytes. Cellular and Molecular Bioengineering. 2020; 13 (3):201-218.
Chicago/Turabian StyleIoannis Tsamesidis; Konstantina Kazeli; Evgenia Lymperaki; Georgia K. Pouroutzidou; Ilias M. Oikonomou; Philomela Komninou; George Zachariadis; Karine Reybier; Antonella Pantaleo; Eleana Kontonasaki. 2020. "Effect of Sintering Temperature of Bioactive Glass Nanoceramics on the Hemolytic Activity and Oxidative Stress Biomarkers in Erythrocytes." Cellular and Molecular Bioengineering 13, no. 3: 201-218.
Graphene oxide (GO) is a chemical compound with a form similar to graphene that consists of one-atom-thick two-dimensional layers of sp2-bonded carbon. Graphene oxide exhibits high hydrophilicity and dispersibility. Thus, it is difficult to be separated from aqueous solutions. Therefore, functionalization with magnetic nanoparticles is performed in order to prepare a magnetic GO nanocomposite that combines the sufficient adsorption capacity of graphene oxide and the convenience of magnetic separation. Moreover, the magnetic material can be further functionalized with different groups to prevent aggregation and extends its potential application. Until today, a plethora of magnetic GO hybrid materials have been synthesized and successfully employed for the magnetic solid-phase extraction of organic compounds from environmental, agricultural, biological, and food samples. The developed GO nanocomposites exhibit satisfactory stability in aqueous solutions, as well as sufficient surface area. Thus, they are considered as an alternative to conventional sorbents by enriching the analytical toolbox for the analysis of trace organic compounds.
Natalia Manousi; Erwin Rosenberg; Eleni Deliyanni; George A. Zachariadis; Victoria Samanidou. Magnetic Solid-Phase Extraction of Organic Compounds Based on Graphene Oxide Nanocomposites. Molecules 2020, 25, 1148 .
AMA StyleNatalia Manousi, Erwin Rosenberg, Eleni Deliyanni, George A. Zachariadis, Victoria Samanidou. Magnetic Solid-Phase Extraction of Organic Compounds Based on Graphene Oxide Nanocomposites. Molecules. 2020; 25 (5):1148.
Chicago/Turabian StyleNatalia Manousi; Erwin Rosenberg; Eleni Deliyanni; George A. Zachariadis; Victoria Samanidou. 2020. "Magnetic Solid-Phase Extraction of Organic Compounds Based on Graphene Oxide Nanocomposites." Molecules 25, no. 5: 1148.
The present study represents the determination of Ti and Cr in dry animal feeds using wet acid digestion and inductively coupled plasma–atomic emission spectrometry (ICP-AES), in order to use these metals as digestibility markers. A radiofrequency power of 1350 W and a nebulizer argon flow of 0.8 L/min was selected. The limits of detection were between 11.4 and 16.1 μg/g for titanium and between 10.7 and 38.2 μg/g for chromium. The recovery values for the aqueous solutions were 89.5–103.9% (titanium) and 85.3–104.2% (chromium), with relative standard deviations (RSD%) under 2.1% and standard errors under 2.32%, demonstrating that the method offered good accuracy and repeatability. Six different samples of commercially available feedstuffs (two cat foods, two dog foods, and two poultry foods) were analyzed and the levels of investigated metals were found to be in the ranges of 0.10 g/kg and
Eleni Tsanaktsidou; George Zachariadis. Titanium and Chromium Determination in Feedstuffs Using ICP-AES Technique. Separations 2019, 7, 1 .
AMA StyleEleni Tsanaktsidou, George Zachariadis. Titanium and Chromium Determination in Feedstuffs Using ICP-AES Technique. Separations. 2019; 7 (1):1.
Chicago/Turabian StyleEleni Tsanaktsidou; George Zachariadis. 2019. "Titanium and Chromium Determination in Feedstuffs Using ICP-AES Technique." Separations 7, no. 1: 1.
Metal–organic frameworks (MOFs) are crystalline porous materials composed of metal ions or clusters coordinated with organic linkers. Due to their extraordinary properties such as high porosity with homogeneous and tunable in size pores/cages, as well as high thermal and chemical stability, MOFs have gained attention in diverse analytical applications. MOFs have been coupled with a wide variety of extraction techniques including solid-phase extraction (SPE), dispersive solid-phase extraction (d-SPE), and magnetic solid-phase extraction (MSPE) for the extraction and preconcentration of metal ions from complex matrices. The low concentration levels of metal ions in real samples including food samples, environmental samples, and biological samples, as well as the increased number of potentially interfering ions, make the determination of trace levels of metal ions still challenging. A wide variety of MOF materials have been employed for the extraction of metals from sample matrices prior to their determination with spectrometric techniques.
Natalia Manousi; Dimitrios A. Giannakoudakis; Erwin Rosenberg; George A. Zachariadis. Extraction of Metal Ions with Metal–Organic Frameworks. Molecules 2019, 24, 4605 .
AMA StyleNatalia Manousi, Dimitrios A. Giannakoudakis, Erwin Rosenberg, George A. Zachariadis. Extraction of Metal Ions with Metal–Organic Frameworks. Molecules. 2019; 24 (24):4605.
Chicago/Turabian StyleNatalia Manousi; Dimitrios A. Giannakoudakis; Erwin Rosenberg; George A. Zachariadis. 2019. "Extraction of Metal Ions with Metal–Organic Frameworks." Molecules 24, no. 24: 4605.