Adsorption Of Chemicals Research Articles

Efficient adsorption and selective separation of high value-added chemicals from simulated expired energy drinks by metal-organic frameworks

Expired energy drinks contain a certain amount of high-value chemicals, such as caffeine, that possess biological activity. The recovery and recycling of these valuable chemicals plays a crucial role in promoting the achievement of carbon emission reduction goals. In this work, 11 kinds of water-stable MOFs with different pore channel structure were synthesized and used for the first time to adsorb caffeine, nicotinic acid, or taurine from water. It has been found that the size effect of the topological structure of MOF adsorbents is the fundamental factor governing their adsorption performance. The optimized adsorbent UiO-67 exhibits excellent adsorption performance for caffeine and nicotinic acid, with respective adsorption capacities of 830 mg/g and 583 mg/g. The investigated MOF has a very low adsorption capacity for taurine (48 mg/g); therefore, selective separation of caffeine/taurine and nicotinic acid/taurine was achieved. The adsorption process can be accurately described by both the Langmuir model and pseudo-second-order model. Adsorption mechanism reveals that the main driving forces of the adsorption process are π-π interaction between UiO-67 and CN in caffeine, as well as hydrogen bonding interactions between the N atom of caffeine’s two CO groups and μ-OH of UiO-67.

Current status, challenges and prospects of antifouling materials for oncology applications.

Targeted therapy has become crucial to modern translational science, offering a remedy to conventional drug delivery challenges. Conventional drug delivery systems encountered challenges related to solubility, prolonged release, and inadequate drug penetration at the target region, such as a tumor. Several formulations, such as liposomes, polymers, and dendrimers, have been successful in advancing to clinical trials with the goal of improving the drug's pharmacokinetics and biodistribution. Various stealth coatings, including hydrophilic polymers such as PEG, chitosan, and polyacrylamides, can form a protective layer over nanoparticles, preventing aggregation, opsonization, and immune system detection. As a result, they are classified under the Generally Recognized as Safe (GRAS) category. Serum, a biological sample, has a complex composition. Non-specific adsorption of chemicals onto an electrode can lead to fouling, impacting the sensitivity and accuracy of focused diagnostics and therapies. Various anti-fouling materials and procedures have been developed to minimize the impact of fouling on specific diagnoses and therapies, leading to significant advancements in recent decades. This study provides a detailed analysis of current methodologies using surface modifications that leverage the antifouling properties of polymers, peptides, proteins, and cell membranes for advanced targeted diagnostics and therapy in cancer treatment. In conclusion, we examine the significant obstacles encountered by present technologies and the possible avenues for future study and development.

Fabrication of Functional Gypsum Boards Using Waste Eggshells to Prevent Sick Building Syndrome

Eggshells can adsorb chemicals, but no studies regarding the adsorption of gaseous chemicals using eggshells or eggshell membranes have been reported. The purpose of this study was to apply chemical adsorption using eggshells to the maintenance of human health. Building materials containing eggshells may reduce the concentrations of toxic substances, such as formaldehyde, via the adsorption functions of eggshells. In the bending study, the strength of board-shaped gypsum-containing eggshells was not compromised when the content of eggshells within the gypsum was ≤10%. Compared to those of gypsum boards containing seashells, which comprise calcium carbonate, similar to eggshells, gypsum containing eggshells displayed a higher strength. In the adsorption study, board-shaped gypsum containing eggshells placed inside a sealed box rapidly decreased the formaldehyde concentration. A gypsum board with an eggshell content of ≥5% could limit the formaldehyde concentration to ≤0.08 ppm. Furthermore, the results were compared with those of adsorption studies using plasterboard mixed with other natural materials. Eggshells displayed excellent functionalities as novel formaldehyde adsorbents.

Synthesis of biochar-ZnAl-layered double hydroxide composite for effective heavy metal adsorption: Exploring mechanisms and structural transformations

Rapid industrialization has increased the extent of heavy metal contamination in water sources, demanding effective wastewater treatment methods. To mitigate this issue, adsorption techniques play a crucial role in wastewater treatment. Layered double hydroxides (LDHs) are commonly employed in such processes; however, they exhibit limitations in effectively adsorbing contaminants. Here, biochar (BC) was incorporated into LDHs using a simple hydrothermal method and subsequently used for Cd2+ and Pb2+ adsorption. Additionally, the physicochemical characteristics of BC and ZnAl-LDH-BC were assessed utilizing various instruments. The obtained ZnAl-LDH-BC400 and ZnAl-LDH-BC600 had surface areas of 52.55 and 102.56 m²/g, respectively, several times greater than those of the original BC. Adsorption performance was investigated using different kinetic and isothermal models. The Langmuir–Freundlich and pseudo-second-order kinetic models demonstrated the adsorption of single-layer chemicals. Furthermore, the highest observed adsorption capacities for Cd2+ and Pb2+ were 99.8 mg g−1 and 128.4 mg g−1, respectively, when using ZnAl-LDH–BC600. In contrast, BC600 demonstrated adsorption capacities of 42.1 mg g−1 for Cd2+ and 51.7 mg g−1 for Pb2+. Cd2+ and Pb2+ adsorption by ZnAl-LDH-BC was primarily governed by surface precipitation and cation exchange processes. These findings highlight the mechanisms underlying the removal of heavy metals using ZnAl-LDH-BC and provide valuable theoretical and applied insights into the management of agricultural waste and control of water pollution.

Nanoplastics increase in vitro oestrogenic activity of neurotherapeutic drugs.

Environmental pollution with plastic nanoparticles (PNPs) has rendered hazard assessment of unintentional human exposure to neurotherapeutic drugs through contaminated water and food ever more complicated. Due to their small size, PNPs can easily enter different cell types and cross different biological barriers, while their high surface-to-volume ratio enables higher adsorption of chemicals. This is how PNPs take the role of a Trojan horse as they enhance bioaccumulation of many different pollutants. One of the health concerns related to water pollution with neurotherapeutic drugs is endocrine disruption, already evidenced for the anticonvulsant drug carbamazepine (Cbz) and antidepressant fluoxetine (Flx). Our study aimed to evaluate endocrine disrupting effects of Cbz and Flx in mixtures with polystyrene nanoparticles (PSNPs) using the in vitro luciferase assay to measure oestrogen receptor activity in T47D-KBluc cells treated with Cbz-PSNPs or Flx-PSNPs mixtures and compare it with the activities observed in cells treated with individual mixture components (Cbz, Flx, or PSNPs). Dose ranges used in the study were 0.1-10 mg/L, 1-100 µmol/L, and 0.1-10 µmol/L for PSNPs, Cbz, and Flx, respectively. Our findings show that none of the individual components activate oestrogen receptors, while the mixtures induce oestrogen receptor activity starting with 0.1 mg/L for PSNPs, 10 µmol/L for Cbz, and 0.5 µmol/L for Flx. This is the first study to evidence that PSNPs increase oestrogen receptor activity induced by neurotherapeutic drugs at their environmentally relevant concentrations and calls for urgent inclusion of complex mixtures in health hazard assessments to inform regulatory response.

Preparation of Lanthanum-Modified Tea Waste Biochar and Its Adsorption Performance on Fluoride in Water.

In this study, tea waste was used as a raw material, and TBC (tea waste biochar) was prepared by pyrolysis at 700 °C. La(NO3)3·6H2O was used as the modifier to optimize one-way modification; the orthogonal experiment was undertaken to determine the optimal preparation conditions; and La-TBC (lanthanum-modified biochar) was obtained. The key factors for the adsorption of fluoride by La-TBC were investigated by means of batch adsorption experiments, and kinetics and isothermal adsorption experiments were carried out on the adsorption of fluoride in geothermal hot spring water. The adsorption mechanism of fluoride by La-TBC was analyzed via characterization methods such as SEM-EDS (Scanning Electron Microscope and Energy Dispersive Spectrometer), BET (Brunauer-Emmett-Teller), FTIR (Fourier transform infrared), XRD (X-ray diffraction), and so on. The results show that La-TBC had the best adsorption effect on fluoride at pH 7. The process of adsorption of fluoride follows the pseudo-second-order kinetics and Langmuir isothermal model, and the maximum theoretical adsorption quantity was 47.47 mg/g at 80 °C, while the removal rate of fluoride from the actual geothermal hot spring water reached more than 95%. The adsorption process was dominated by the monolayer adsorption of chemicals, and the mechanisms mainly include pore filling, ion exchange, and electrostatic interaction.

A mechanochemically synthesized Schiff-base engineered 2D mixed-linker MOF for CO2 capture and cationic dye removal.

Developing synthetic strategies for smart materials for the adsorption and separation of toxic chemicals is of great importance. Metal-organic frameworks (MOFs) have been proven to be outstanding adsorbent materials that possess excellent pollutant removal performances in wastewater treatment, including dye recycling. In this work, a neutral Cd(II) based 2D framework with a dual ligand strategy involving -OH functionalized 5-hydroxyisophthalic acid (5-OH-H2IPA) and the amide decorated Schiff base ligand (E)-N'-(pyridin-4-ylmethylene)isonicotinohydrazide (L) has been synthesized by different synthetic routes and characterized by various analytical methods. Thus, crystals of {[Cd(5-OH-IPA)(L)]·CH3OH}n synthesized via diffusion (ADES-7D) and the phase pure bulk product synthesized by conventional reflux (ADES-7C) and the mechanochemical grinding method (ADES-7M) have been established using PXRD data of the respective product showing identical simulated SXRD data to those of ADES-7D. The mechanochemically synthesized ADES-7M possesses a better surface area and CO2 adsorption capability compared to ADES-7C, which is also supported by electron microscopy and particle size measurements. Furthermore, ADES-7 can be used as an efficient adsorbent material for the reversible, selective adsorption (42-99%) and separation of the cationic dyes malachite green (MG), methyl violet (MV), methylene blue (MB), and rhodamine B (RhB) from the mixture of cationic/anionic dyes (methyl orange (MO) and bromocresol green (BCG)) in the aqueous phase. Specifically, ADES-7M possesses better dye capture capability compared to ADES-7C, even in the case of the bigger dye RhB with adsorption differences of 2.38 to 1.01 mg g-1, respectively. The dye adsorption kinetics follows pseudo-second-order kinetics, and the dye adsorption isotherm fits well with the Langmuir/Freundlich adsorption isotherm models. The probable mechanism of adsorption involving the supramolecular interaction between the host MOF and the guest dye has also been proposed.

Predicting adsorption of organic compounds onto graphene and black phosphorus by molecular dynamics and machine learning.

With an increase in production and application of various engineering nanomaterials (ENMs), they will inevitably be released into the environment. Adsorption of various organic chemicals onto ENMs will impact on their environmental behavior and toxicology. It is unrealistic to experimentally determine adsorption equilibrium constants (K) for the vast number of organics and ENMs due to high cost in expenditure and time. Herein, appropriate molecular dynamics (MD) methods were evaluated and selected by comparing experimental K values of seven organics adsorbed onto graphene with the MD-calculated ones. Machine learning (ML) models on K of organics adsorption onto graphene and black phosphorus nanomaterials were constructed based on a benchmark data set from the MD simulations. Lasso models based on Mordred descriptors outperformed ML models built by support vector machine, random forest, k-nearest neighbor, and gradient boosting decision tree, in terms of cross-validation coefficients (Q2 > 0.90). The Lasso models also outperformed conventional poly-parameter linear free energy relationship models for predicting logK. Compared with previous models, the Lasso models considered more compounds with different functional groups and thus have broader applicability domains. This study provides a promising way to fill the data gap in logK for chemicals adsorbed onto the ENMs.

Microplastics Scoping Review of Environmental and Human Exposure Data

Scientific studies of microplastics have expanded since 2015, propelling the topic to the forefront of scientific inquiry. Microplastics are ubiquitous in the environment and pose a potential risk to human health. The purpose of this review is to organize microplastics literature into areas of scientific research, summarize the state of the literature and identify the current data gaps in knowledge to promote a better understanding of human exposure to microplastics and their potential health effects. We searched for published literature from eight databases. Our search focused on three categories: (1) microplastics in the environment, (2) adsorption and absorption of chemicals to microplastics, and (3) human exposure to microplastics in the environment. We screened all abstracts to select articles that focused on microplastics. We then screened the remaining articles using criteria outlined in a questionnaire to identify and assign articles to the three scoping review categories. After screening abstracts, we selected 1186 articles (19%) to thoroughly assess their appropriateness for inclusion in the final review. Of the 1186 articles, 903 (76.1%) belonged to the environmental category, 268 (22.6%) to the adsorption and absorption category, and 16 (1.3%) to the human exposure category. Water was the most frequently studied environmental medium (440 articles). Our assessment resulted in 572 articles selected for the final review. Of the 572 publications, 268 (48.2%) included a geographic component and 110 (19.2%) were the product of literature reviews. We also show that relatively few publications have investigated human health effects associated with exposures to microplastics.

Plant-growth promotion by biochar-organic amendments mixtures explained by selective chemicals adsorption of inhibitory compounds

Biochar is known to promote plant growth and is marketed worldwide as a soil amendment. However, benefits of pure biochar on crop yields are, in some cases, limited, while its mixture with non-pyrogenic organic amendments (NPOAs) has a more consistent stimulatory effect. Here, we studied the biochar effect together with three NPOAs (fishmeal, Medicago, and maize straw) used alone and in all possible combinations on the growth of lettuce (Lactuca sativa), soybean (Glycine max), maize (Zea mays), and rice (Oryza sativa). The bulk fraction of organic materials was characterized by 13 C-CPMAS NMR spectroscopy and the liquid fraction by liquid chromatography-mass spectrometry (LC-MS). Biochar and NPOAs showed different effects, ranging from inhibition to strong stimulation of crops. For NPOAs, the major inhibitory effects were found in undecomposed materials, especially fishmeal with a low C/N ratio and a high nitrogen. The effect of the mixture depended on the chemical quality of the NPOAs and the target species, with fishmeal having a common synergistic effect on soybean and lentils. 13C-CPMAS NMR showed major changes in the bulk fraction of biochar-NPOA mixtures enriched in carbonyl C, alkyl C, and O-alkyl C types. Moreover, LC-MS showed a large effect of biochar in the liquid fraction by selective adsorption of many putative chemical compounds, especially when mixed with fishmeal and Medicago straw. This approach clarifies for the first time that biochar extensively adsorbs a number of organic compounds from the NPOA feedstock, which not only causes significant detoxification but also triggers remarkable biostimulation of plant growth.

Assessment of corrosion inhibition performance of origanum compactum extract for mild steel in 1 M HCl: Weight loss, electrochemical, SEM/EDX, XPS, DFT and molecular dynamic simulation

In this study, plant ethanolic extract OCEE (Origanum Compactum Ethanolic Extract), a promising natural product with a cheap cost, was used as a green and sustainable mild steel corrosion inhibitor in a 1 M HCl solution. Chemical, electrochemical, surface analysis, and quantum chemical calculations were used to examine the inhibitory efficacy of OCEE on mild steel(MS) corrosion. Overall, the findings show that OCEE has excellent corrosion inhibitory characteristics, with a 90 % inhibitory efficacy at a dosage of 400 mg/L. The plots of Potentiodynamic Polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) demonstrate that the OCEE is a mixed type corrosion inhibitor and that the corrosion process is regulated by charge transfer, respectively. The Langmuir adsorption isotherm adequately characterized the adsorption of OCEE. OCEE has considerably higher activation thermodynamic characteristics than the blank. SEM/EDX surface examination shows that the OCEE may connect to the metal surface by producing a barrier layer, and XPS research confirms bonds between functional groups and the MS substrate. The electronic characteristics of the main OCEE compound were studied using the DFT technique (density functional theory), and the sites sensitive to electron sharing were discovered using the Fukui indices. Furthermore, MD (molecular dynamics) modelling was utilized to predict the spontaneous adsorption of this significant chemical on a mild steel surface.

Polymeric Microfluidic Devices Fabricated Using Epoxy Resin for Chemically Demanding and Day-Long Experiments.

Polydimethylsiloxane (PDMS) is a widely used material in laboratories for fabricating microfluidic devices with a rapid and reproducible prototypingability, owing to its inherent properties (e.g., flexibility, air permeability, and transparency). However, the PDMS channel is easily deformed under pressures applied to generate flows because of its elasticity, which can affect the robustness of experiments. In addition, air permeability of PDMS causes the pervaporation of water, and its porous structure absorbs oil and even small hydrophobic molecules, rendering it inappropriate for chemically demanding or day-long experiments. In this study, we develop a rapid and reproducible fabrication method for polymer-based rigid microfluidic devices, using epoxy resin that can overcome the limitations of PDMS channels, which are structurally and chemically robust. We first optimize a high-resolution fabrication protocol to achieve convenient and repeatable prototyping of polymeric devices via epoxy casting using PDMS soft molds. In addition, we compare the velocity changes in PDMS microchannels by tracking fluorescent particles in various flows (~133 μL/min) to demonstrate the structural robustness of the polymeric device. Furthermore, by comparing the adsorption of fluorescent hydrophobic chemicals and the pervaporation through channel walls, we demonstrate the excellent chemical resistance of the polymeric device and its suitability for day-long experiments. The rigid polymeric device can facilitate lab-on-chip research and enable various applications, such as high-performance liquid chromatography, anaerobic bacterial culture, and polymerase chain reaction, which require chemically or physically demanding experiments.

The Effect of Tedlar Bags on the Composition of Exhaled Human Breath Samples.

The PVF Tedlar is widely used for gas collection in clinical diagnostics and environmental research. However, sample collection is frequently associated with the degradation, adsorption, or transformation of sensitive chemicals. Here, we explore to what extent the Tedlar bag collection effects the composition of expired breath samples. Collected breath samples were analyzed using the EESI-MS technique after the storage time of 30 min, 1 h, 2 h, 3 h, 4 h, 5 h, and 6 h, respectively. Our results demonstrated the gradual MS signal decay after 3 h storage. The decay rate of 3 h is about 45% and 6 h is about 88%. Therefore, the Tedlar bag is suggested as a reliable breath holder on the time scale of <3 h.

Fate and impact of nano/microplastic in the geoenvironment — ecotoxicological perspective

Plastic pollution in the terrestrial environment is emerging as another significant human-made threat to ecosystem function and health. Plastic contamination can range from the macro- to the nanoscale, and environmental impacts are evident at each level. Although significant knowledge gaps remain regarding the interactions between the natural environment and nano- and microplastics (NMPs), there is an increasing body of evidence concerning detrimental effects on a wide range of taxa. The surface properties of NMPs lead to the adsorption of heavy metals, endocrine-disrupting chemicals, antibiotics and other persistent organic pollutants, which, therefore, can result in their co-migration in the terrestrial environment. Although airborne and dietary transmission routes of NMPs have been observed, their effects on human health are still not fully understood, which is of concern to the scientific community. This state-of-the-art review paper firstly examines available evidence for, and knowledge of, various sources of NMP contamination to the terrestrial environment. Attention then focuses on (a) the biological processes from the source to soils and plants, (b) potential impacts of NMPs on soil and subsurface ecosystems, (c) trophic interactions and function and (d) implications for environmental and human health. This paper concludes by identifying knowledge gaps and presents recommendations on prioritised research needs.

Evaluating the adsorption performance of functional building material with HCHO remover

Dubai Municipality is making significant efforts to reduce the concentration of chemical substances in major buildings via Green Building Regulations &amp;amp; Specifications. However, it has limitations to the problem because it simply regulates the indoor air concentration of some harmful substances from building materials. The functional building materials capable of adsorbing and decomposing indoor pollutants such as Formaldehyde (HCHO) and Volatile Organic Compounds (VOCs) are gradually spreading. This paper aims to evaluate the performance of functional building materials and analyze the effect of improving the indoor air environment. As a methodology, the investigation was done to research trends and standards for functional building standards. 20 L small chamber experiment was performed for wallpaper with 0%, 5%, 7%, 10%, and 15% of the ethylene urea (C5H10N2O3), HCHO remover. The result showed standard wallpaper’s adsorption rate on the seventh day was 6.21%. The formaldehyde remover adsorption rate for 7 days was 50.43% when formaldehyde remover was added at a 5 wt% (weight percentage); 60.21% when it was added at 7 wt%; 63.45% when it was added at 10 wt%; and 73.58% when it was added at 15 wt%. The adsorption rate on the seventh day with 7 wt%, 10 wt%, and 15 wt% HCHO remover showed a 60% or more (IS O 16000-24 standard). However, wallpaper with 15 wt%, displayed the highest value, was 5.736 μg/m2, which did not satisfy the IS O 16000-24 standard (6.000 μg/m2). It was statistically proven when the amount of the HCHO remover is increased; the adsorption performance is improved in proportion to the amount added. This study will serve as primary data to prepare UAE standards for the functional building materials with adsorption and decomposition performance of harmful chemicals, moisture absorption and moisture-proof performance, and antibacterial/anti-fungal performance.

Tailoring the structure of layered double oxide for enhancing adsorption of anionic chemicals on collagen fibers in chrome-free leather processing

Tailoring the structure of layered double oxide for enhancing adsorption of anionic chemicals on collagen fibers in chrome-free leather processing

Dual functionality of ultralow levels of a model kinetic hydrate inhibitor on hydrate particle morphology and interparticle force

Gas hydrate plug formation is a major concern in oil and gas exploitation efforts, wherein line blockages can pose major safety, economic, and environmental risks. Kinetic hydrate inhibitors (KHIs) are a promising class of hydrate management chemicals, which are potentially cleaner, cheaper, and greener than traditional thermodynamic hydrate inhibitors (THIs). Therefore, understanding the effects that KHIs have on hydrate particles is vital to their application. In this study, polyvinylpyrrolidone (PVP), a model KHI, was investigated at ultralow concentrations to determine its effect on the properties of hydrates and elucidate when nucleation and growth inhibition begins. It was found that PVP can adsorb at the hydrate particle surface to reduce interparticle force by 40–54 %. Low concentration PVP continues to affect interparticle forces at prolonged contact times, reducing forces at 30-minutes to 1-hour of contact by 20–40 % and reducing sintering rate. PVP also reduces film growth rates by 30–50 % depending on the concentration of PVP in the water phase. The onset of major nucleation and growth effects was observed to occur at 0.01 wt% PVP in the water phase, two orders of magnitude below concentrations typically employed in hydrate management. It was discovered that low dosage PVP can cause major morphological changes to the hydrate particles in both the short and long term, which can influence interparticle forces and particle agglomeration, and may serve as a morphological screening tool for KHIs. A proposed mechanism for the observed morphology changes explains how the heterogenous adsorption of chemicals at the particle surface can lead directly to the newly observed particle morphology. The results presented in this paper show that ultralow concentrations of KHIs (0.0005 wt%) can have combined effects on the interfacial activity and crystal growth and morphology of hydrates, showing KHIs to be a dual function inhibitor of both interparticle interactions and hydrate growth. These results can inform KHI applications from industrial flow assurance to carbon dioxide transport for unimpeded carbon capture and sequestration.

Adsorption behaviors of triclosan by non-biodegradable and biodegradable microplastics: Kinetics and mechanism

Microplastics (MPs) pollution has been becoming serious and widespread in the global environment. Although MPs have been identified as vectors for contaminants, adsorption and desorption behaviors of chemicals with non-biodegradable and biodegradable MPs during the aging process is limited. In this work, the adsorption behaviors of triclosan (TCS) by non-biodegradable polyethylene (PE) and polypropylene (PP), and biodegradable polylactic acid (PLA) were investigated. The differences in morphology, chemical structures, crystallization, and hydrophilicity were investigated after the ultraviolet aging process and compared with the virgin MPs. The results show that the water contact angles of the aged MPs were slightly reduced compared with the virgin MPs. The aged MPs exhibited a stronger adsorption capacity for TCS because of the physical and chemical changes in MPs. The virgin biodegradable PLA had a larger adsorption capacity than the non-biodegradable PE and PP. The adsorption capacity presented the opposite trend after aging. The main adsorption mechanism of MPs relied on hydrophobicity interaction, hydrogen bonding, and electrostatic interaction. The work provides new insights into TCS as hazardous environmental contaminants, which will enhance the vector potential of non-biodegradable and biodegradable MPs.

The Inhibition of Microcystin Adsorption by Microplastics in the Presence of Algal Organic Matters.

Microplastics (MPs) could act as vectors of synthetic chemicals; however, their influence on the adsorption of chemicals of natural origin (for example, MC-LR and intracellular organic matter (IOM), which could be concomitantly released by toxic Microcystis in water) is less understood. Here, we explored the adsorption of MC-LR by polyethylene (PE), polystyrene (PS), and polymethyl methacrylate (PMMA). The results showed that the MPs could adsorb both MC-LR and IOM, with the adsorption capability uniformly following the order of PS, PE, and PMMA. However, in the presence of IOM, the adsorption of MC-LR by PE, PS, and PMMA was reduced by 22.3%, 22.7% and 5.4%, respectively. This is because the benzene structure and the specific surface area of PS facilitate the adsorption of MC-LR and IOM, while the formation of Π-Π bonds favor its interaction with IOM. Consequently, the competition for binding sites between MC-LR and IOM hindered MC-LR adsorption. The C=O in PMMA benefits its conjunction with hydroxyl and carboxyl in the IOM through hydrogen bonding; thus, the adsorption of MC-LR is also inhibited. These findings highlight that the adsorption of chemicals of natural origin by MPs is likely overestimated in the presence of metabolites from the same biota.

Wrap-and-plant technology to manage sustainably potato cyst nematodes in East Africa

Renewable eco-friendly options for crop protection are fundamental in achieving sustainable agriculture. Here, we demonstrate the use of a biodegradable lignocellulosic banana-paper matrix as a seed wrap for the protection of potato plants against potato cyst nematode (PCN), Globodera rostochiensis. Potato cyst nematodes are devastating quarantine pests of potato globally. In East Africa, G. rostochiensis has recently emerged as a serious threat to potato production. Wrapping seed potatoes within the lignocellulose banana-paper matrix substantially reduced G. rostochiensis field inoculum and increased potato yields by up to fivefold in Kenya, relative to farmer practice, whether or not impregnated with ultra-low doses of the nematicide abamectin (ABM). Markedly, ABM-treated banana paper at ~1,000 times lower than conventional recommendations reduced PCN inoculum. Assays and analyses revealed that the lignocellulose matrix disrupts parasite–host chemical signalling by adsorbing critical PCN hatching and infective juvenile host location chemicals present in potato root exudate. Recovery experiments confirmed adsorption of these host location chemicals. Our study demonstrates the use of waste organic material to sustainably manage PCN, and potentially other crop root pests, while increasing potato yields.