Discarded substrates from soilless hydroponic horticulture as potential amendments for metal-contaminated soils.

Soil contamination with metals is a major threat for the environment and public health since most metals are toxic to humans and to non-human biota, even at low concentrations. Thus, new sustainable remediation approaches are currently needed to immobilize metals in soils to decrease their mobility and bioavailability. In this work, we explore the application of discarded substrates from hydroponic cultivation, namely coconut shell and a mixture of coconut shell and pine bark, for immobilization of metals (Cd, Cr, Ni, Cu, Pb, Hg, Sb and As) in a naturally contaminated soil from a mining region in Portugal.

Enhancing tomato plants' tolerance to combined heat and salt stress - The role of arbuscular mycorrhizae and biochar.

The Mediterranean basin is highly susceptible to climate change, with soil salinization and the increase in average temperatures being two of the main factors affecting crop productivity in this region. Following our previous studies on describing the detrimental effects of heat and salt stress co-exposure on tomato plants, this study aimed to understand if substrate supplementation with a combination of arbuscular mycorrhizal fungi (AMF) and biochar could mitigate the negative consequences of these stresses. Upon 21 days of exposure, stressed tomato plants grown under supplemented substrates showed increased tolerance to heat (42 °C for 4 h/day), salt (100 mM NaCl), and their combination, presenting increased biomass and flowering rate.

Multivariate analysis applied to X-ray fluorescence to assess soil contamination pathways: case studies of mass magnetic susceptibility in soils near abandoned coal and W/Sn mines.

Determining the origin and pathways of contaminants in the natural environment is key to informing any mitigation process. The mass magnetic susceptibility of soils allows a rapid method to measure the concentration of magnetic minerals, derived from anthropogenic activities such as mining or industrial processes, i.e.

Unravelling the combined impacts of drought and Cu in barley plants - double trouble?

The occurrence of drought in soils, particularly in those contaminated by metals, poses a current threat to crops, as these factors can interact and induce unique stress responses. Therefore, this study mainly focused on understanding the crosstalk between drought and copper (Cu) stress in the physiology of the barley (Hordeum vulgare L.) plant.

Recent Advances in Light-Driven Semiconductor-Based Micro/Nanomotors: Optimization Strategies and Emerging Applications.

Micro/nanomotors represent a burgeoning field of research featuring small devices capable of autonomous movement in liquid environments through catalytic reactions and/or external stimuli. This review delves into recent advancements in light-driven semiconductor-based micro/nanomotors (LDSM), focusing on optimized syntheses, enhanced motion mechanisms, and emerging applications in the environmental and biomedical domains. The survey commences with a theoretical introduction to micromotors and their propulsion mechanisms, followed by an exploration of commonly studied LDSM, emphasizing their advantages.

Imprinted Hydrogel Nanoparticles for Protein Biosensing: A Review.

Over the past decade, molecular imprinting (MI) technology has made tremendous progress, and the advancements in nanotechnology have been the major driving force behind the improvement of MI technology. The preparation of nanoscale imprinted materials, i.e.

Molecularly Imprinted Methyl-Modified Hollow TiO Microspheres.

The possibility of generating organically modified hollow TiO microspheres via a simple sol-gel synthesis was demonstrated for the first time in this work. A mixture of titania precursors, including an organically modified precursor, was used to obtain methyl-modified hollow TiO microspheres selective for bilirubin by the molecular imprinting technique (Methyl-HTM-MIM). Methyl-HTM-MIM were prepared by a sol-gel method using titanium (IV) isopropoxide (TTIP), and methyltitanium triisopropoxide (MTTIP) as precursors.

Subcellular compartmentalization of aluminum reduced its hazardous impact on rye photosynthesis.

Aluminum (Al) toxicity limits crops growth and production in acidic soils. Compared to roots, less is known about the toxic effects of Al in leaves. Al subcellular compartmentalization is also largely unknown.

Impact of Combined Heat and Salt Stresses on Tomato Plants-Insights into Nutrient Uptake and Redox Homeostasis.

Currently, salinity and heat are two critical threats to crop production and food security which are being aggravated by the global climatic instability. In this scenario, it is imperative to understand plant responses to simultaneous exposure to different stressors and the cross-talk between underlying functional mechanisms. Thus, in this study, the physiological and biochemical responses of tomato plants ( L.

Specific glutathione-S-transferases ensure an efficient detoxification of diclofenac in Solanum lycopersicum L. plants.

Diclofenac (DCF) is a very common pharmaceutical that, due to its high use and low removal rate, is considered a prominent contaminant in surface and groundwater worldwide. In this study, Solanum lycopersicum L. cv.

Foliar application of 24-epibrassinolide improves Solanum nigrum L. tolerance to high levels of Zn without affecting its remediation potential.

Although Solanum nigrum L. is a phytoremediator for different metals, its growth and physiology are still compromised by toxic levels of zinc (Zn). Thus, the development of eco-friendly strategies to enhance its tolerance, maintaining remediation potential is of special interest.

Exploration of the reactive modelling of sol-gel polycondensation in the presence of templates.

The polycondensation of silicic acid, methylsilicic acid, or their mixture was studied by reactive force field simulation. These were found to be feasible systems for the simulation of two-step acid hydrolysis-alkaline condensation of their alkoxysilane counterparts, usually taken experimentally as sol-gel precursors. The approach avoided the alkoxysilane hydrolysis step and allowed high degrees of polycondensation at relatively low temperature (700-1000 K), from the computational efficiency perspective.

Differential effects of acetophenone on shoots' and roots' metabolism of Solanum nigrum L. plants and implications in its phytoremediation.

The wide ranges of uses for acetophenone make it more available and expected to accumulate in the biosphere, where consequently it can threat ecosystems. To remediate this problem, the use of Solanum nigrum L. plants for the clean-up of acetophenone-contaminated sites was explored.

Metalaxyl Effects on Antioxidant Defenses in Leaves and Roots of L.

Overuse of pesticides has resulted in environmental problems, threating public health through accumulation in food chains. Phytoremediation is a powerful technique to clean up contaminated environments. However, it is necessary to unravel the metabolic mechanisms underlying phytoremediation in order to increase the efficiency of this process.

SiO nanomaterial as a tool to improve Hordeum vulgare L. tolerance to nano-NiO stress.

This work was designed to assess the potential role of silicon dioxide nanomaterial (nano-SiO) in enhancing barley's tolerance to nickel oxide nanomaterial (nano-NiO). For this purpose, plants were grown for 14days under nano-NiO (120mgkg) single and co-exposure with nano-SiO (3mgkg). The exposure of barley to nano-NiO caused a significant decrease in growth-related parameters and induced a negative response on the photosynthetic apparatus.

Cationic imprinting of Pb(II) within composite networks based on bovine or fish chondroitin sulfate.

Imprinting chondroitin sulfate (CS)/silica composites with Pb(II) and Cu(II) cations was explored with CS of bovine and different fish species origin. The process was based on the assumption that particular arrangements of the linear CS chains in aqueous solution, induced so as to accommodate cross complexation with the cations, would be embodied into a tridimensional matrix created through an organoalkoxysilane sol-gel scheme. The presence of Cu(II) in the synthesis of the composites did not result in the production of significantly stronger Cu(II)-oriented binding arrangements, and therefore, the imprinting was not successful.

Acylated-naproxen as the surface-active template in the preparation of micro- and nanospherical imprinted xerogels by emulsion techniques.

A strategy based on water-in-oil emulsion for the dispersion of a sol-gel mixture into small droplets was employed with the view of the production of naproxen-imprinted micro- and nanospheres. The procedure, aiming at a surface imprinting process, comprised the synthesis of a naproxen-derived surfactant. The imprinting process occurred at the interface of the emulsions or microemulsions, by the migration of the NAP-surfactant head into the sol-gel drops to leave surficial imprints due mainly to ion-pair interaction with a cationic group contained within the growing sol-gel network.

Naproxen-imprinted xerogels in the micro- and nanospherical formsby emulsion technique.

Naproxen-imprinted xerogels in the microspherical and nanospherical forms were prepared by W/O emulsion and microemulsion, respectively. The work evolved from a sol–gel mixture previously reported for bulk synthesis. It was relatively simple to convert the original sol–gel mixture to one amenable to emulsion technique.

Aminoglutethimide-imprinted xerogels in bulk and spherical formats, based on a multifunctional organo-alkoxysilane precursor.

The multifunctional alkoxysilane precursor, 2,6-bis(propyl-trimethoxysilylurelene)pyridine (DPS) was designed and synthesized, envisaging a multiple hydrogen-bond interaction in the molecular imprinting of the drug aminoglutethimide (AGT). Imprinted xerogels were obtained in bulk and spherical formats. The spherical format was achieved by pore-filling onto spherical mesoporous silica, as a straightforward technique to generate the spherical format.

Measurement artifacts identified in the UV-vis spectroscopic study of adduct formation within the context of molecular imprinting of naproxen.

The ultraviolet-visible spectroscopy has been assessed as a technique for the evaluation of the strength of template-precursor adduct in the development of molecular imprints of the non-steroidal anti-inflammatory drug naproxen (NAP). The commonly employed approach relies on the collection of UV spectra of drug+precursor mixtures at different proportions, the spectra being recorded against blanks containing the same concentration of the precursor. The observation of either blue or red band-shifts and abatement of a major band are routinely attributed to template-precursor adduct formation.

Molecularly imprinted sol-gel materials for medical applications.

The present review deals with the sol-gel imprinting of both drug and non-drug templates of medical relevance, namely neurotransmitters, biomarkers, hormones, proteins and cells. Nearly a hundred recent works, either developmental or applied in a medical-related context, were critically analyzed. It may be concluded that, although research is still at an early stage, the potential of these sol-gel materials was well demonstrated in a few applications of critical interest for medicinal/biomedical science.

Molecular dynamics simulations of complex mixtures aimed at the preparation of naproxen-imprinted xerogels.

The main objective of this study was to simulate for the first time a complex sol-gel system aimed at preparing the (S)-naproxen-imprinted xerogel with an explicit representation of all the ionic species at pH 9. For this purpose, a series of molecular dynamics (MD) simulations of different mixtures, including species never studied before using the OPLS-AA force field, were prepared. A new parametrization for these species was developed and found to be acceptable.

Recognitive nano-thin-film composite beads for the enantiomeric resolution of the metastatic breast cancer drug aminoglutethimide.

Straightforward crushing and sieving bulk polymeric R-aminoglutethimide-imprinted materials were prepared by classical free radical polymerization, whereas nano thin walled grafted imprinted materials were prepared using RAFT mediated control polymerization technique. A stoichiometric non-covalent approach based on a triply hydrogen bonding functional monomer-template 1:1 complex (K=599mol(-1)L(-1)) led to chiral selectors far outperforming previously used selectors for resolving this racemate. The recognitive materials produced here (enantioselectivity factors, α∼10) also have no match within the previously reported enantioselective imprinted polymers (α 1.

Chromatographycally efficient microspherical composites of molecularly imprinted xerogels deposited inside mesoporous silica.

A different approach to the preparation of microspheric particles of molecularly imprinted xerogels (MIX) is presented here. The technique consisted of filling up the pores of spherical, mesoporous, bare silica particles with a pregelification mixture by applying pressure. Upon gelification and drying, thin layers of MIX were deposited on the mesopores.

Vapor-phase testing of the memory-effects in benzene- and toluene-imprinted polymers conditioned at elevated temperature.

The preparation of polymers imprinted with common aromatic solvents such as benzene and toluene is an under-exploited subject of research. The present study was aimed at the understanding of whether true solvent memory effects can be achieved by molecular imprinting, as well as if they are stable at elevated temperature. A set of copolymers, comprising low and high cross-linking levels, was prepared from four different combinations of functional monomer and cross-linker, namely methacrylic acid (MAA)/ethylene glycol dimethacrylate (EGDMA), methyl methacrylate (MMA)/EGDMA, MAA/divinyl benzene (DVB) and MMA/DVB.