A supercritical fluid chromatography‐tandem mass spectrometry (SFC‐MS/MS) technique was developed for the rapid and simultaneous detection of nine pesticides (carbendazim, isoprocarb, paclobutrazol, ...isoprothiolane, flusilazole, quinalphos, piperonylbutoxide, propargite, and bioresmethrin) in rice, wheat, and maize. The cereal samples were extracted with a solution of 0.5% acetic acid in acetonitrile and purified using quick, easy, cheap, effective, rugged, and safe method. The samples were characterized using multi‐reaction monitoring and quantified with the external standard method. Excellent linearities (R2 > 0.9991) and limits of quantification (0.4–40.0 μg/kg) were established for all nine pesticides. Satisfactory pesticide recovery rates (62.2%–107.4%) were obtained at three standard concentrations (50, 100, and 200 μg/kg), with relative standard deviations in the range of 2.1%–14.3%. The results confirmed that the proposed method was suitable for the routine detection of these pesticides in grain samples. Compared with high‐performance liquid chromatography‐MS/MS, the overall test run time and the amount of solvent required were reduced by 66% and 90%, respectively, when SFC‐MS/MS was applied. Therefore, the use of SFC‐MS/MS permits a shorter run time and affords greater analytical efficiency, such that it is both economical and environmentally sustainable.
A nontarget screening method was developed based on D‐optimal designs for ultra‐high performance supercritical fluid chromatography with positive and negative electrospray ionization mode mass ...spectrometry. A mixture of organic contaminants such as pesticides, steroids, surfactants, phenolic and fatty acids, and polycyclic aromatic hydrocarbon derivatives, was used for the optimization. An aprotic mixture of dichloromethane and acetone 3:1 performed overall best as the injection solvent. The highest peak capacities (n) were accomplished at the shallowest gradient (1%B/min), ammonium formate (n = 378 in negative ionization mode), or ammonium acetate (n = 327 in positive ionization mode) in methanol as the modifier. Capillary voltage, make‐up solvent flow rate, water, and additive concentration were the most significant factors for improving peak intensity: higher peak intensities were obtained at lower additive concentrations (5mM ammonium formate), and with 5% water in positive ionization mode. Conversely, water had detrimental effects in negative ionization mode. The optimized method was used to quantify organic contaminants in 17 freshwater sediment samples from Copenhagen, Denmark. Out of 50 monitored contaminants, 35 were detected in at least one sample. Further, the method has a potential for target and nontarget screening analysis of organic contaminants in solid matrices.
Extraction is the first step for isolation and purification of interesting bioactive compounds, by mixing of the plant material with an adequate solvent. Those bioactive compounds are, usually, ...secondary metabolites, such as phenolic acids and flavonoids which are present in closed insoluble structures, making its extraction a challenge. There are many different traditional extraction methods, such as Soxhlet, heat reflux, and maceration. Nevertheless, due to several disadvantages, they are being replaced by new methods, using emergent technologies, such as high hydrostatic pressure, ultrasounds, pulsed electric fields, and supercritical fluids. The use of novel technologies allows enhancing mass transfer rates, increasing cell permeability as well as increasing secondary metabolite diffusion, leading to higher extraction yields, fewer impurities on the final extract, extractions at room temperature with thermo-sensitive structures preservation, use of different non-organic solvents, low energy consumption, short operation time, and have no significant or lower effect on the structure of bioactive compounds. This paper aims to review the effect of the main emergent extraction technologies (high hydrostatic pressure, pulsed electric fields, ultrasounds, and supercritical fluid assisted) on the individual profile of bioactive compounds from plant material.
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•Conventional extractions methods present several disadvantages.•Non-thermal technologies are in development to enhance the extraction process.•These new methods are more efficient for bioactive compounds extraction.•Non-thermal extraction technologies allow to preserve heat-labile compounds.
•UHPSFC belongs in compendium of methods for drug analysis.•UHPSFC produced superior resolution of positional isomers and diastereomers.•UHPSFC is highly orthogonal to both UHPLC and GC.
The recent ...development of modern methods for ultra high performance supercritical fluid chromatography (UHPSFC) has great potential for impacting the analysis of seized drugs. In the separation of synthetic cannabinoids the technique has the potential to produce superior resolution of positional isomers and diastereomers.
To demonstrate this potential we have examined the capability of UHPSFC for the analysis of two different groups of synthetic cannabinoids. The first group was a mixture of 22 controlled synthetic cannabinoids, and the second group included JWH018 and nine of its non-controlled positional isomers The clear superiority of UHPSFC over other separation techniques was demonstrated, in that it was capable of near baseline separation of all 10 positional isomers using a chiral column. In total we examined four achiral columns, including Acquity UPC2 Torus 2-PIC, Acquity UPC2 Torus Diol, Acquity UPC2 Torus DEA and Acquity UPC2 Torus 1-AA (1.7μm 3.0×100mm), and three chiral columns, including Acquity UPC2 Trefoil AMY1, Acquity UPC2 Trefoil CEL1 and Acquity UPC2 Trefoil CEL2 (2.5μm 3.0×150mm), using mobile phase compositions that combined carbon dioxide with methanol, acetonitrile, ethanol or isopropanol modifier gradients. Detection was performed using simultaneous PDA UV detection and quadrupole mass spectrometry. The orthogonality of UHPSFC, GC and UHPLC for the analysis of these compounds was demonstrated using principal component analysis. Overall we feel that this new technique should prove useful in the analysis and detection of seized drug samples, and will be a useful addition to the compendium of methods for drug analysis.
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•Current state of polymer foaming with supercritical carbon dioxide.•Foaming of rubbers, copolymers, blends, thermosetting polymers.•Challenges in assessment of thermal transitions ...and rheological properties of polymers in CO2.•Challenges in modeling of foaming, scale up and processing.
In this paper, we examine the state of the art of the physical foaming of polymers with supercritical fluids with a primary focus on carbon dioxide. We provide a critical analysis of the current research pathways and the main scientific open questions. We discuss the knowledge gaps along with technological challenges for further advances. Perspectives on the foaming of amorphous and semi-crystalline polymers, polymer blends, copolymers, and thermosetting polymers are presented. Challenges pertaining to the improved understanding of the nucleation phenomena and the limitations on the modeling and processing methodologies are discussed.
Until less than 10 years ago, chiral separations were carried out with columns packed with 5 or 3 μ m fully porous particles (FPPs). Times to resolve enantiomeric mixtures were easily larger than 30 ...min, or so. Pushed especially by stringent requirements from medicinal and pharmaceutical industries, during the last years the field of chiral separations by liquid chromatography has undergone what can be defined a "true revolution". With the purpose of developing ever faster and efficient method of separations, indeed, very efficient particle formats, such as superficially porous particles (SPPs) or.
Phenolic compounds present in common beans (
L.) have been reported to possess antimicrobial, anti-inflammatory and ultraviolet radiation (UVR) protective properties. UVR from sunlight, which ...consists of UV-B and UV-A radiations, induces reactive oxygen species (ROS) and free radical formation, consequently activating proteinases and enzymes such as elastase and tyrosinase, leading to premature skin aging. The objective of this work was to extract, characterize and evaluate the antioxidant and antiaging potential of polyphenols from a black bean endemic variety. The polyphenolic extract was obtained from black beans by supercritical fluid extraction (SFE) using CO
with a mixture of water-ethanol as a cosolvent and conventional leaching with a mixture of water-ethanol as solvent. The polyphenolic extracts were purified and characterized, and antioxidant potential, tyrosinase and elastase inhibitory potentials were measured. The extract obtained using the SFE method using CO
and H
O-Ethanol (50:50
/
) as a cosolvent showed the highest total phenolic compounds yield, with 66.60 ± 7.41 mg GAE/g coat (
> 0.05) and 7.30 ± 0.64 mg C3GE/g coat (
< 0.05) of anthocyanins compared to conventional leaching. Nineteen tentative phenolic compounds were identified in leaching crude extract using ESI-QTOF. Quercetin-3-D-galactoside was identified in crude and purified extracts. The purified SFC extract showed IC
0.05 ± 0.002 and IC
0.21 ± 0.008 mg/mL for DPPH and ABTS, respectively. The lowest IC
value of tyrosinase inhibition was 0.143 ± 0.02 mg/mL and 0.005 ± 0.003 mg/mL of elastase inhibition for leaching purified extract. Phenolic compounds presented theoretical free energy values ranging from -5.3 to -7.8 kcal/mol for tyrosinase and -2.5 to -6.8 kcal/mol for elastase in molecular docking (in silico) studies. The results suggest that the purified extracts obtained by SFE or conventional leaching extraction could act as antioxidant and antiaging ingredients for cosmeceutical applications.
•Eugenol-loaded LLDPE films were obtained by supercritical CO2 impregnation at 45°C.•Higher impregnation yields were obtained at slow depressurization (0.5–1MPa/min).•Films showed antioxidant ...activity via DPPH inhibition.•High pressure impregnation reduced polymer crystallinity and ductility but not its tensile strength.
In this work, linear low density polyethylene (LLDPE) films were impregnated with eugenol using supercritical CO2 impregnation, as a strategy for obtaining a loaded material to be potentially applied in active food packaging. Eugenol, the main component of clove oil, is well known as a natural antioxidant and antimicrobial agent. Impregnation runs were performed in a lab-scale high pressure stirred cell at 45°C during 4h, and the effect of pressure (10, 12 and 15MPa) and depressurization rate (0.5, 1 and 5MPa/min) on impregnation yield was evaluated. Yields of 1–6% (w/w) were achieved, with higher values at low depressurization rate. Film samples were characterized by infra-red spectroscopy (FTIR) and differential scanning calorimetry (DSC). FTIR analysis suggested that the distribution of eugenol in the films is not totally homogeneous. DSC revealed a decrease in the crystallinity degree in the impregnated samples as well as in films subjected to pressurization with CO2 but not loaded with eugenol. Changes in mechanical properties were also investigated in a texturometer. A decrease of LLDPE Young modulus and ductility was observed after high pressure impregnation, although tensile strength was not significantly affected. Finally, the antioxidant activity of the eugenol-loaded films was assessed via the DPPH inhibition test.
The recent COVID-19 pandemic has underscored the need for innovative decontamination techniques capable of treating sensitive materials potentially contaminated. Combining supercritical carbon ...dioxide (scCO2) with sterilant agents has shown promise in this regard. This study aimed at testing scCO2 as a virus inactivation method for biomedical materials contaminated with the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2). The virus was inoculated on a stainless-steel carrier and treated at 45 °C and 8 MPa. No inactivation was detected when only scCO2 was used, even after long treatment times (60 min). The addition of 50 ppm of H2O2 to the process allowed the inactivation of more than 5 Log PFU (Plaque Forming Unit) of the virus by only pressurising and depressurising the vessel, while a 20-min process is needed by only using H2O2. Overall, the study demonstrates a synergistic effect when H2O2 is added to the scCO2 process for the inactivation of SARS-CoV-2.
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•An experimental setup for supercritical CO2 without pump was validated.•SARS-CoV-2 sterilisation was achieved with a small amount of H2O2.•Synergism between supercritical CO2 and H2O2 was verified.
Propolis is a natural product with many demonstrated biological activities and propolis extract has been used in the food, pharmaceutical and cosmetics industries. Different works have showed the ...variations in the chemical composition, and consequently, on the biological activity of the propolis that are associated with its type and geographic origin. Due to this study evaluated propolis extracts obtained through supercritical extraction and ethanolic extraction (conventional) in three samples of different types of propolis (red, green and brown), collected from different regions in Brazil (state of Bahia). Analyses were performed to determine the humidity, water activity, the content of total ash, proteins, lipids and fiber in raw propolis samples. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH), catechin, ferulic acid and luteolin and antimicrobial activity against two bacteria (Staphylococcus aureus and Escherichia coli) were determined for all extracts. For the green and red ethanolic extracts the anti-leishmanicidal potential was also evaluated. The physicochemical profiles showed agreement in relation to the literature. The results identified significant differences among the extracts (p>0.05), which are in conformity with their extraction method, as well as with type and botanical origin of the samples. The extraction with supercritical fluid was not efficient to obtain extracts with the highest contents of antioxidants compounds, when compared with the ethanolic extracts. The best results were shown for the extracts obtained through the conventional extraction method (ethanolic) indicating a higher selectivity for the extraction of antioxidants compounds. The red variety showed the largest biological potential, which included the content of antioxidants compounds. The results found in this study confirm the influence of the type of the raw material on the composition and characteristics of the extracts. The parameters analysis were important to characterize and evaluate the quality of the different Brazilian propolis extracts based on the increased use of propolis by the natural products industry.
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