Competitive heavy metal adsorption on pinecone shells: Mathematical modelling of fixed-bed column and surface interaction insights.

Pinecone shells are assessed as a cost-effective biosorbent for the removal of metal ions Pb(II), Cu(II), Cd(II), Ni(II), and Cr(VI) in a fixed-bed column. Influent concentration, bed height, and flowrate are studied to improve efficiency. The breakthrough data is well fitted by the Sips adsorption model, suggesting a surface complexation mechanism, with maximum adsorption capacities of 11.1 mg/g for Cu(II) and 66 mg/g for Pb(II). In multimetal solutions, the uptake sequence at breakthrough and saturation is Pb(II) > Cu(II) > Cd(II). Characterization via FTIR and XRD reveals carboxyl and hydroxyl functional groups interacting with metal ions. Ca(II) does not compete with Pb(II), Cu(II), and Cd(II) adsorption, highlighting the ability of pinecone to adsorb heavy metals via surface complexation. Its application in the treatment of industrial effluents containing Cu(II), Ni(II), and Cr(VI) is explored. The study investigates bed media regeneration via eluting adsorbed metal ions with hydrochloric acid solutions. The potential of pinecone shells as an efficient biosorbent for removing toxic metal ions from industrial wastewater is emphasized. These findings enhance our understanding of the adsorption mechanism and underscore the fixed-bed column system's applicability in real-world scenarios, addressing environmental concerns related to heavy metal contamination of industrial effluents.

Degradation of Azo Dye Solutions by a Nanocrystalline Fe-Based Alloy and the Adsorption of Their By-Products by Cork.

In this study, the efficiency of mechanically alloyed Fe80Si10B10 in degrading basic red 46 azo dye is investigated. Moreover, the influences of different parameters, such as pH and time, on the elimination of the aromatic derivatives obtained as by-products of the fracture of the azo group are also analyzed. After beginning the reduction to the normal conditions of pH (4.6) and temperature, the experimental findings showed a discoloration of 97.87% after 20 min. The structure and morphology of the nanocrystalline Fe80Si10B10 powder were characterized by SEM and XRD before and after use in the degradation process. The XRD patterns of the Fe-Si-B powder after redox reaction suggest that the valent zero Fe of the alloy is the reducing agent. Powdered cork was then used as a biosorbent for the removal of the by-products generated, resulting in increasing removal percentages from pH 7 (26%) to pH 9 (62%) and a contact time of 120 min. The FTIR spectrum of the cork after adsorption shows a shift of the bands, confirming the interaction with the aromatic amines. The present findings show that metallic powders and natural cork perform well together in removing azo dye solutions and their degradation products.

Artificial Neural Networks Coupled with MALDI-TOF MS Serum Fingerprinting To Classify and Diagnose Pathological Pain Subtypes in Preclinical Models.

Pathological pain subtypes can be classified as either neuropathic pain, caused by a somatosensory nervous system lesion or disease, or nociplastic pain, which develops without evidence of somatosensory system damage. Since there is no gold standard for the diagnosis of pathological pain subtypes, the proper classification of individual patients is currently an unmet challenge for clinicians. While the determination of specific biomarkers for each condition by current biochemical techniques is a complex task, the use of multimolecular techniques, such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), combined with artificial intelligence allows specific fingerprints for pathological pain-subtypes to be obtained, which may be useful for diagnosis. We analyzed whether the information provided by the mass spectra of serum samples of four experimental models of neuropathic and nociplastic pain combined with their functional pain outcomes could enable pathological pain subtype classification by artificial neural networks. As a result, a simple and innovative clinical decision support method has been developed that combines MALDI-TOF MS serum spectra and pain evaluation with its subsequent data analysis by artificial neural networks and allows the identification and classification of pathological pain subtypes in experimental models with a high level of specificity.

Detection of SARS-CoV-2 Infection in Human Nasopharyngeal Samples by Combining MALDI-TOF MS and Artificial Intelligence.

The high infectivity of SARS-CoV-2 makes it essential to develop a rapid and accurate diagnostic test so that carriers can be isolated at an early stage. Viral RNA in nasopharyngeal samples by RT-PCR is currently considered the reference method although it is not recognized as a strong gold standard due to certain drawbacks. Here we develop a methodology combining the analysis of from human nasopharyngeal (NP) samples by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with the use of machine learning (ML). A total of 236 NP samples collected in two different viral transport media were analyzed with minimal sample preparation and the subsequent mass spectra data was used to build different ML models with two different techniques. The best model showed high performance in terms of accuracy, sensitivity and specificity, in all cases reaching values higher than 90%. Our results suggest that the analysis of NP samples by MALDI-TOF MS and ML is a simple, safe, fast and economic diagnostic test for COVID-19.

Zooplankton-based reactors for tertiary wastewater treatment: A pilot-scale case study.

Nature-based wastewater treatments are an economic and sustainable alternative to intensive technologies in rural areas, although their efficiency needs to be improved. This study explores technological co-operation between zooplankton (e.g., Daphnia magna) and bacterial and algal biofilms in a 1.5 m3 zooplankton-based reactor for the on-site treatment of secondary urban wastewater. The efficiency of the reactor was evaluated over a 14-month period without any maintenance. The results suggest a low seasonality effect on nutrient polishing (organic matter and nitrogen) and the removal of solids (TSS and turbidity). The best performance, involving a decrease in organic carbon, nitrogen, E. coli loads, and solid content was achieved in winter when operating the reactor at 750 L d-1. Under these conditions, the quality of the effluent water was suitable for its reuse for six different purposes in conformance with Spanish legislation. These results demonstrate that the zooplankton-based reactor presented here can be used as an eco-sustainable tertiary treatment to provide water suitable for reuse. On-site research revealed that the robustness of the reactor against temperature and oxygen fluctuations needs to be improved to ensure good performance throughout the year.

Synergistic effects of water temperature, microplastics and ammonium as second and third order stressors on Daphnia magna.

Daphnids, including the water flea Daphnia magna, can be exploited for wastewater treatment purposes, given that they are filter feeder organisms that are able to remove suspended particles from water. The presence of pollutants, such as microplastics and chemicals, might be considered stressors and modify the behaviour and survival of D. magna individuals. The impact of the cumulative pollutants that regulate the fate of living organisms has yet to be fully determined. Here we present the effect of double and triple combinations of stressors on the behaviour of D. magna. The impact of water temperature, ammonium and polystyrene microplastics on the filtration capacity and survival of D. magna is studied. Water temperatures of 15 °C, 20 °C and 25 °C, microplastic-to-food ratios of 25% and 75%, and ammonium concentrations of 10 and 30 mg N-NH4+ L-1 are tested after making dual and triple combinations of the parameters. A synergistic effect between water temperature and ammonium is normally observed but not in the case of the lower values of ammonium concentration and temperature. The combination of three stressors (water temperature, microplastics and ammonium) is also found to be synergistic, producing the greatest impact on D. magna filtration capacity and reducing their survival. In comparison with the effect of the two stressor conditions, the combination of the three stressors caused a reduction of between 13.1% and 91.7% in the t50% time (the time required for a 50% reduction in the D. magna filtration capacity) and a reduction of between 4.8% and 54.5% in TD50 (the time for 50% mortality).

Assessment of zooplankton-based eco-sustainable wastewater treatment at laboratory scale.

The combination of the filtration capacity of zooplankton (e.g. Daphnia) with the nutrient removal capacity of bacterial/algal biofilm in a zooplankton-containing reactor could provide a natural-based alternative for wastewater treatment. A laboratory-scale zooplankton-based reactor was tested at different HRTs resulting in a significant reduction in nutrient concentrations in wastewater when the system was operated at HRTs longer than 1.1 days (preferably of between 2 and 4 days). However, the presence of high concentrations of organic matter (>250 mg COD L-1) in the wastewater inhibited zooplankton activity, limiting its use to tertiary treatment. Therefore, in combination with other natural treatments that can perform primary and secondary treatments, zooplankton may provide a solution for wastewater clarification and nutrient polishing. The effect of a common metal such as copper on the filtration capacity of Daphnia was also evaluated. Daphnia, as well as the whole zooplankton-based reactor, adapted to copper concentrations of up to 70 µg Cu L-1 but an overload of 380 µg Cu L-1 for two-weeks severely affected the biological system.

A Polydimethylsiloxane Rod Extraction-Based Method for the Determination of Pharmaceuticals and Triclosan by Liquid Chromatography in Water Samples.

A new analytical method for the determination of naproxen, ketoprofen, diclofenac, carbamazepine, and triclosan (TCS) in water samples by liquid chromatography is developed and validated. The method is based on the extraction of the analytes by a polydimethylsiloxane (PDMS) rod. The different parameters affecting extraction, such as the addition of salt, pH, initial volume, extraction and elution times and elution solvent, as well as the application of sonication, are studied. The results showed that the detection limits are all in the 0.1-0.3 µg L-1 range except for carbamazepine (6 µg L-1) with relative standard deviations in the range of 0.4%-9.7%. The method developed, which was validated by analysing spiked surface water samples at 10, 25 and 75 µg L-1 gave recoveries of between 84.8% and 111.2%. In the case of carbamazepine, a recovery of 99.1% was obtained at 75 µg L-1. The main advantage of the developed method is that allows high performance liquid chromatography-diode array detection, which is widely available in non-specialised laboratories, to be applied for pharmaceuticals and TCS determination in surface waters after performing a preconcentration/clean-up step with PDMS rods as it has been shown by analysing real water samples.

Optimal light conditions for Daphnia filtration.

Daphnia populations are present in lakes and ponds. They are known to experience diurnal vertical migrations according to their feeding needs. During the day they migrate downwards to avoid predation in light-receiving layers and at night they migrate upwards, searching for food in the shallow productive layers. The light photoperiod and light intensity vary depending on the latitude and, therefore, the precise location of lakes and ponds will be an additional and crucial parameter in determining the development of Daphnia. Here we will focus on a population of Daphnia magna (a genus of the Cladocera order). The effect of both light intensity and photoperiod on Daphnia filtration was studied in laboratory experiments. An increase in the light intensity resulted in two D. magna responses depending on the exposure time of individuals to light. Short time exposures to a decrease in the light intensity of less than one day produced an increase in the D. magna filtration. However, exposures of longer than one day resulted in a decrease in the D. magna filtration along with a decrease in the light intensity. Photoperiod exposures of 8, 12 and 16 h produced greater D. magna filtrations than photoperiods of 0, 4 and 24 h. In this study, regulation of the light intensity and the period of exposure were used in laboratory experiments to establish D. magna development thresholds by latitudinal variation in the photoperiod.

Rapid discrimination of multiple myeloma patients by artificial neural networks coupled with mass spectrometry of peripheral blood plasma.

Multiple myeloma (MM) is a highly heterogeneous disease of malignant plasma cells. Diagnosis and monitoring of MM patients is based on bone marrow biopsies and detection of abnormal immunoglobulin in serum and/or urine. However, biopsies have a single-site bias; thus, new diagnostic tests and early detection strategies are needed. Matrix-Assisted Laser Desorption/Ionization Time-of Flight Mass Spectrometry (MALDI-TOF MS) is a powerful method that found its applications in clinical diagnostics. Artificial intelligence approaches, such as Artificial Neural Networks (ANNs), can handle non-linear data and provide prediction and classification of variables in multidimensional datasets. In this study, we used MALDI-TOF MS to acquire low mass profiles of peripheral blood plasma obtained from MM patients and healthy donors. Informative patterns in mass spectra served as inputs for ANN that specifically predicted MM samples with high sensitivity (100%), specificity (95%) and accuracy (98%). Thus, mass spectrometry coupled with ANN can provide a minimally invasive approach for MM diagnostics.

Design of a Hollow Fiber Supported Liquid Membrane System for Zn Speciation in Natural Waters.

A supported liquid membrane-hollow fiber system (HFSLM) has been developed to determine zinc speciation in aquatic environments. The liquid membrane consisted of an organic solution of bis-(2-ethylhexyl)phosphoric acid (D2EHPA) impregnated in the microporous of a polypropylene hollow fiber. The membrane contacted both the donor solution, that contained the metal and the stripping solution, placed in the lumen of the hollow fiber, where the metal was preconcentrated. Different parameters affecting the Zn2+ transport efficiency have been evaluated such as the composition of both the donor and stripping solutions as well as the membrane phase. Extraction and transport efficiencies of free Zn(II) higher than 90% were obtained with a liquid membrane consisting of a 0.1 M D2EHPA solution in dodecane and a 0.1 M HNO3 solution as the stripping phase. The developed HFSLM was used to study the effect of different ligands (EDTA and citric acid) in the donor phase of Zn(II) transport and to investigate the selectivity of the membrane towards Zn when other metals were also present. Finally, the HFSLM system was successfully applied to estimate the free Zn(II) concentrations in three water samples from a mining area. Moreover, the HFSLM system facilitates the analytical determination of trace Zn(II) levels allowing the achievement of enrichment factors of around 700 in the stripping phase.

Granulated cork as biosorbent for the removal of phenol derivatives and emerging contaminants.

This study evaluated the ability of cork to adsorb a broad range of phenolic, pharmaceutical and cosmetic compounds: phenol, 2-chlorophenol, 2-nitrophenol, 2,4-dichlorophenol, pentachlorophenol carbamazepine, naproxen, ketoprofen, diclofenac, triclosan, and methyl paraben. The effect of variables such as the compound concentrations and the amount of cork were studied resulting in a highly pH dependence in the case of phenolic compounds. Maximum removal percentages and uptake values of 75% (1.61 mg/g) for 2,4-dichlorophenol, 55% (1.25 mg/g) for 2-nitrophenol, 45% (1.47 mg/g) for 2-chlorophenol, 20% (0.63 mg/g) for phenol, and 100% for pentachlorophenol, were obtained for a 30 mg L-1 solution at pH 6, showing that the adsorption process increased with greater electronegativity of the phenolic substituting group. Removal percentages and uptakes of 82% (3.56 mg/g) for naproxen, 57% (2.31 mg/g) for ketoprofen, 50% (1.84 mg/g) for carbamazepine, 50% (1.78 mg/g) for methyl paraben, 100% for sodium diclofenac, and 100% for triclosan, were obtained using 5 mg of cork and a 1 mg L-1 solution of each compound. The adsorption process was almost complete after 30 min for all the micropollutants. Experimental equilibrium data were analysed by Freundlich and Langmuir adsorption models. Cork has proved to be an effective sorbent for the removal of phenols and emerging contaminants from contaminated waters and is a readily available material that can be acquired at minimal or no cost in cork-producing areas.

Applicability of a Supported Liquid Membrane in the Enrichment and Determination of Cadmium from Complex Aqueous Samples.

A supported liquid membrane is developed for the separation of Cd from either high in salinity or acidity aqueous media. The membrane consisted of a durapore (polyvinylidene difluoride) polymeric support impregnated with a 0.5 M Aliquat 336 solution in decaline. The effect of carrier concentration, organic solvent and feed and receiving solutions on the metal permeability is studied. This system allows the effective transport of trace levels of Cd through the formation of CdCl42−, which is the predominant species responsible for the extraction process, in both NaCl and HCl solutions. The supported liquid membrane system in a hollow fibre configuration allows the enrichment and separation of trace levels of Cd from spiked seawater samples, facilitating the analytical determination of this toxic metal.

The Identification and Quantification of Suberin Monomers of Root and Tuber Periderm from Potato (Solanum tuberosum) as Fatty Acyl tert-Butyldimethylsilyl Derivatives.

INTRODUCTION: Protective plant lipophilic barriers such as suberin and cutin, with their associated waxes, are complex fatty acyl derived polyesters. Their precise chemical composition is valuable to understand the specific role of each compound to the physiological function of the barrier. OBJECTIVES: To develop a method for the compositional analysis of suberin and associated waxes by gas chromatography (GC) coupled to ion trap-mass spectrometry (IT-MS) using N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) as sylilating reagent, and apply it to compare the suberin of the root and tuber periderm of potato (Solanum tuberosum). METHODOLOGY: Waxes and suberin monomers from root and periderm were extracted subsequently using organic solvents and by methanolysis, and subjected to MTBSTFA derivatisation. GC analyses of periderm extracts were used to optimise the chromatographic method and the compound identification. Quantitative data was obtained using external calibration curves. The method was fully validated and applied for suberin composition analyses of roots and periderm. RESULTS: Wax and suberin compounds were successfully separated and compound identification was based on the specific (M-57) and non-specific ions in mass spectra. The use of calibration curves built with different external standards provided quantitative accurate data and showed that suberin from root contains shorter chained fatty acyl derivatives and a relative predominance of α,ω-alkanedioic acids compared to that of the periderm. CONCLUSION: We present a method for the analysis of suberin and their associated waxes based on MTBSTFA derivatisation. Moreover, the characteristic root suberin composition may be the adaptive response to its specific regulation of permeability to water and gases. Copyright © 2016 John Wiley & Sons, Ltd.

A sensitive multi-residue method for the determination of 35 micropollutants including pharmaceuticals, iodinated contrast media and pesticides in water.

A sensitive, multi-residue method using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to determine a representative group of 35 analytes, including corrosion inhibitors, pesticides and pharmaceuticals such as analgesic and anti-inflammatory drugs, five iodinated contrast media, ß-blockers and some of their metabolites and transformation products in water samples. Few other methods are capable of determining such a broad range of contrast media together with other analytes. We studied the parameters affecting the extraction of the target analytes, including sorbent selection and extraction conditions, their chromatographic separation (mobile phase composition and column) and detection conditions using two ionisation sources: electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI). In order to correct matrix effects, a total of 20 surrogate/internal standards were used. ESI was found to have better sensitivity than APCI. Recoveries ranging from 79 to 134 % for tap water and 66 to 144 % for surface water were obtained. Intra-day precision, calculated as relative standard deviation, was below 34 % for tap water and below 21 % for surface water, groundwater and effluent wastewater. Method quantification limits (MQL) were in the low ng L(-1) range, except for the contrast agents iomeprol, amidotrizoic acid and iohexol (22, 25.5 and 17.9 ng L(-1), respectively). Finally, the method was applied to the analysis of 56 real water samples as part of the validation procedure. All of the compounds were detected in at least some of the water samples analysed. Graphical Abstract Multi-residue method for the determination of micropollutants including pharmaceuticals, iodinated contrast media and pesticides in waters by LC-MS/MS.

Two polydimethylsiloxane rod extraction methods for the sensitive determination of phenolic compounds in water samples.

Simple, precise, and low-cost methods for the simultaneous determination of phenolic endocrine disrupting compounds such as bisphenol A, trichlorophenol, pentachlorophenol, 4-nonylphenol, and 4-octylphenol in water samples were developed. The Direct, in situ derivatization methods are based on polydimethylsiloxane rod extraction followed by liquid desorption and chromatographic analysis by liquid chromatography and diode array detection. Several parameters affecting the extraction and desorption of the phenolic compounds and their acetylated derivates were studied, as well as the chromatographic and detection conditions. For the direct method, determination coefficients (r(2) ) > 0.990 and LODs in the 0.6-2 µg/L range were obtained for all compounds except bisphenol A (9.5 µg/L). With the derivatization-based method, based on in situ acetylation, lower limits of detection (0.3-0.9 µg/L) were obtained for all the compounds with r(2) > 0.988 and RSDs in the 2-9% range. The developed methods were applied to the analysis of spiked water samples obtaining recoveries of between 60.2 and 131.7% for the direct method, and of between 76.6 and 108.2% for the derivatization-based method. The results demonstrate the feasibility of using these two methods for determining bisphenol A, trichlorophenol, pentachlorophenol, 4-nonylphenol, and 4-octylphenol in water.

The ability of biologically based wastewater treatment systems to remove emerging organic contaminants--a review.

Biologically based wastewater treatment systems are considered a sustainable, cost-effective alternative to conventional wastewater treatment systems. These systems have been used and studied for the treatment of urban sewage from small communities, and recently, it has been reported that they can also effectively remove emerging organic contaminants (EOCs). EOCs are a new group of unregulated contaminants which include pharmaceutical and personal care products, some pesticides, veterinary products, and industrial compounds among others that are thought to have long-term adverse effects on human health and ecosystems. This review is focused on reporting the ability of biologically based wastewater treatment systems to remove EOCs and the main elimination mechanisms and degradation processes (i.e., biodegradation, photodegradation, phytoremediation, and sorption) taking place in constructed wetlands, ponds, and Daphnia and fungal reactors.

Determination of antibiotics (tetracyclines and sulfonamides) in biosolids by pressurized liquid extraction and liquid chromatography-tandem mass spectrometry.

A robust and sensitive analytical method is developed to quantitatively determine tetracyclines and sulfonamides, two major antibiotic classes, in sewage sludge. The antibiotic agents, oxytetracycline, tetracycline, dioxycycline, chlorotetracycline, sulfathiazole, sulfapyridine, sulfamethazine and sulfamethoxazole, were extracted using pressurized liquid extraction (PLE) with citric acid at pH 3 and methanol (1:1 v/v). Clean-up of the extracts was performed by solid phase extraction (SPE) with hydrophilic-lipophilic balance cartridges. Identification and quantification of the compounds is by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring (MRM) mode. High recoveries ranging from 90.4 to 99.9% for sulfonamides and 96.2 to 100.9% for the tetracyclines are obtained. Method detection limits (MDLs) range from 0.6 to 4.2 ng/g for sulfonamides and 3.2 to 13 ng/g for tetracyclines. After validation, the method is applied to the analysis of sludges collected from different WWTPs in Spain.

Application of polydimethylsiloxane rod extraction to the determination of sixteen halogenated flame retardants in water samples.

An extraction and preconcentration procedure for the determination in water samples of several halogenated flame retardants (FRs), nine brominated diphenyls ethers (BDEs) and seven non-BDE FRs, was developed and validated. The optimised procedure is based on polydimethylsiloxane (PDMS) rods as sorptive extraction material, followed by liquid desorption and gas chromatography coupled to negative chemical ionisation-mass spectrometry (GC-NCI-MS) determination, rendering an efficient and inexpensive method. The final optimised protocol consists of overnight extraction of 100mL of sample solutions containing 40% MeOH and 4% NaCl, followed by a 15-min sonication-assisted desorption with 300 µL of ethyl acetate, solvent evaporation and GC-NCI-MS analysis. Under these conditions, extraction efficiencies in the 9 to 70% range were obtained, leading to enrichment factors between 108 and 840, detection limits in the range from 0.4 to 10 ng L(-1)and RSD values in the 2-23% range. After method validation, different real water samples, including river, ria, sea, landfill leachate, influent and effluent wastewater from an urban sewage treatment plant (STP) and effluent wastewater from a textile industry, were analysed. BDE-47, BDE-99, BDE-100 and BDE-197 were detected in wastewater and landfill leachate samples at concentration levels up to 2887 ng L(-1). Among the non-BDE FRs, bis (2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (DEHTBP) was detected in surface water samples (sea, river and ria) between 1.3 and 2.2 ng L(-1) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) in the landfill leachate (64 ng L(-1)).

Evaluation of a coagulation/flocculation-lamellar clarifier and filtration-UV-chlorination reactor for removing emerging contaminants at full-scale wastewater treatment plants in Spain.

The presence and elimination of 25 emerging contaminants in two full-scale Spanish wastewater treatment plants was studied. The tertiary treatment systems consisted of coagulation, flocculation lamellar settlement and filtration (pulsed-bed sand filters) units, and disinfection was carried out by medium pressure UV light lamps and chlorination. Diclofenac and carbamazepine were found to be the emerging contaminants with the highest concentrations in secondary effluents. Photodegradable emerging contaminants (e.g. ketoprofen, triclosan and diclofenac) were removed by filtration-UV light radiation-chlorination whereas most hydrophobic compounds (e.g. galaxolide and tonalide) were eliminated by coagulation-flocculation followed by lamellar clarification, a unit in which a seasonal trend was observed. Overall mass removal efficiency was about 60%. 1-(8-Chlorocarbazolyl) acetic acid, an intermediate product of the photodegradation of diclofenac, was detected after filtration-UV-chlorination, but not after coagulation-flocculation and lamellar clarification. This study demonstrated potential for general applicability of two established tertiary treatment systems to eliminate emerging contaminants.