Previous studies clearly indicated that membrane enzymes - ATPases i.e. Na, K-ATPase and Mg-ATPase, responded to presence of various organic and inorganic pollutants. In this work effect of mercury and cadmium on these enzymes activities was investigated in synaptic plasma membranes partially immobilized on microliter plate. Comparing those activities with the control enzyme activities obtained with native and partially immobilized mambranes it was concluded that: a. both metals exerted a concentration-dependent inhibition of investigated enzymes, b. for partially immobilized membranes estimated half maximum inhibition (IC50) values for Na, K-ATPase were IC50 (Hg) = 0.9 micromol/cubic cm, IC50 (cd) = 35 micromol/cubic cm and for Mg - ATPase IC50 (Hg) = 3.5 micromol/cubic cm, IC50 (Cd) = 36 micromol/cubic cm; for native membranes IC50 for Na,K-ATPase were IC50 (Hg) =3.3 micromol/cubic cm, IC50 (Cd) = 2 micromol/cubic cm and for Mg ATPase IC50 (Hg) = 2.3 micromol/cubic cm, IC50 (Cd) = 0.2 mmol/cubic cm. Obtained results indicate avaibility of microtitar plates for partially immobilization of membranes with aim to form a new biosensor for heavy metals detection.

Possibilities of application of transmembrane enzymes as a biological component of a biosensor for water quality control and detection of toxical substances were performed. Synaptic plasma membranes (SPMs) were adsorbed on nitrocellulose filters. The adsorption of SPMs was followed by determination of the transmembrane enzyme Na,K-ATPase. The optimal conditions for SPM adsorption on nitrocellulose filters were determined: 25 microgram per nitrocellulose filter disc during 1 hour of incubation, on - 20 deg C. The ATPase activity of adsorbed SPM showed, that almost 30% of enzymic activity was detected on nitrocellulose filters in mentioned conditions. This results showed that adsorption of SPM on solid support enhancing enzymatic stability and enable its industrial and analytical application.

Spectrophotometric method for determination of inorganic phosphate liberated in hydrolysis of ATP catalyzed by ATPase was modified in order to obtain faster procedure, which could also be used in none laboratory conditions. The modification has some advantages compared to the most used Pennial method: a) the reagents are stable for several months; b) the 45 min procedure of phosphomolibdate extraction by isobutanole-benzene is ommited, and the method is not dangerous for the analyst; c) color develops after 20 min. The method was tested on the determination of inorganic phosphate in the presence of cadmium nitrate as inhibitor of ATPase activity. The results were compared to the results obtained by Pennial method. The results obtained have shown some good agreements.

In our earlier work, we have shown that enzymes from rat brain synaptosomal membranes, Na(+)/K(+)-ATPase and Mg(2+)-ATPase, are promising biological components of a biosensor for lead detection. In this work, we represent our results of investigation with the same enzymes as biological components for the biosensor in presence of Hg(2+) ions in water. It was established that IC50 for Na(+)/K(+)-ATPase and Mg(2+)-ATPase is 6.9 and 5.5 x 10E-6 M, and the percentages of inhibition are 96% and 77% respectively. We concluded that these enzymes could be the base for developing biosensors for the presence of Hg(2+) ion in water. Since these enzymes maintain a stable activity for a longer period of time, they could be appropriate as components of biosensors for monitoring water quality.

Activities of rat brain synaptic plasma membrane (SPM)Na(+)/K(+)-ATPase and Mg(2+)-ATPase were investigated by in vitro individual and simultaneous exposure to ions of the first transition series metals (Cu(2+), Zn(2+), Fe(2+)). All investigated metals produced a larger maximum inhibition of Na(+)/K(+)-ATPase than Mg(2+)-ATPase activity. Metal concentrations causing 50% inhibition of Na(+)/K(+)-ATPase activities were: Cu(2+) 7.1 microM Zn(2+) 19 microM Fe(2+) 25 microM. Simulataneous exposure to metal combinations: Cu(2+)/Zn(2+), Cu(2+)/Fe(2+) and Zn(2+)/Fe(2+) inhibited both the Na(+)/K(+)-ATPase and Mg(2+)-ATPase activity synergistically, i.e., more than the sum of the metal induced inhibitions assayed separately. It is also established that the plot of logarithm IC50 values of Na(+)/K(+)-ATPase activity vs. the ionic radius of (Cu(2+), Zn(2+), Fe(2+)) is a straight line that enables to predict the value IC50 for other metals of the first transition series. The results obtained show that Na(+)/K(+)-ATPase is promising as a biological component of biosensor.

Hydrothermal carbonization is considered a powerful technology to convert sewage sludge (SS) into a valuable carbonaceous solid known as hydrochar (HC). Up to now criteria for landfill application of SS and HC are based only on physicochemical properties and levels of pollutant residues. Nevertheless, to ensure their safe environmental applications it is mandatory to develop biosensors which can provide relevant information on their toxic potential for natural ecosystems. Therefore, this study aimed to assess the suitability of a contact assay using zebrafish embryo/larvae combined with sub-lethal end-points to evaluate the hazard associated with SS and related HC exposure. A suite of biomarkers was also applied on larvae, related to detoxification and oxidative stress as the activity of Ethoxyresorufin-O-deethylase, glutathione-S-transferase, and catalase, the content of reactive oxygen species and the behavioral assay using the DanioVision™ chamber. Legacy priority pollutants were also measured either in SS and HC tested samples and in contact waters. The exposure to SS caused higher lethality compared to HC. No significant changes in the activity of oxidative stress markers was observed upon exposure to both matrices. The behavioral test showed a hypoactivity condition in larvae exposed to both SS and HC with the effects of SS stronger than HC. Chemical analysis revealed the presence of trace elements and halogenated compounds in either SS, HC. Heavy metals were also released in contact waters, while volatile hydrocarbons (C6–C10) and halogenated compounds resulted below LOD (<0.05 μ L⁻¹). Our study highlights the suitability of zebrafish embryotoxicity test, coupled with behavioral traits, as screening tool for assessing potential risks, associated with the landfill application of both SS and HC, for aquatic wildlife.

As a widely used pure elemental carbon in colloidal particles, carbon black was listed as a group 2B carcinogen by IARC in 2010. The most available mechanism information about carbon black and carcinogenesis are from in vivo or in vitro studies. However, few studies concerned the nanoparticle's real-ambient exposure causing systemic change and further affecting the target organ. Herein, we used an ex vivo biosensor assay to investigate the transcriptome change of primary bronchial epithelial cells after treatment with the plasma from workers with long-term occupational carbon black exposure history. Based on ex vivo biosensor assay and transcriptome sequencing, we found the effect of internal systemic environment on epithelial cells after carbon black exposure was an inflammatory response, which mainly activates cell cycle-related pathways. After exposure to carbon black, the internal systemic environment could activate cancer-related pathways like epithelial-mesenchymal transition, hypoxia, TNF-α signaling via NF-κB. The hub genes in the carbon black group (CDC20 and PLK1) and their correlation with the systemic environment were uncovered by constructing the protein-protein interaction network. Inflammatory cytokines, especially CRP, were strongly correlated with the expression of CDC20 and PLK1. Besides, we also find a strong correlation between CDC20 and cytokinesis-block micronucleus endpoints in peripheral blood (rho = 0.591, P < 0.001). Our results show that long-term carbon black exposure might activate cell cycle-related pathways through circulating inflammation and increase the risk of cancer, while the oxidative stress caused by diesel exhaust particles are mainly related to PAHs exposure. After exposure to carbon black, the systemic environment could activate cancer-related pathways like diesel exhaust particles, increasing the risk of lung cancer. These attempts might provide a further understanding of the indirect effect of chronic occupational inhaled carbon black exposure on pulmonary carcinogenesis.

The increased occurrence of Mercury (Hg II) contaminant has caused environmental and health concerns worldwide. Removal of Hg(II) from water is of significant interest, in particular if these can be coupled in a manner of detection. Here, a novel activated carbon (AC) adsorbent and a fast detection device to form a closed-cycle strategy was developed. The synthesis of conjugates of streptavidin-biotinylated DNA probes modified gold nanoparticle was used with lateral flow biosensors for Hg(II) detection. A quantification was completed via a self-developed smartphone app and its limit of detection was 2.53 nM. Moreover, AC was activated with a new activating agent of diammonium hydrogen phosphate. The adsorbent was characterized and determined to have an amorphous microporous structure with a high surface area (1076.5 m² g⁻¹) and demonstrated excellent removal efficiency (99.99%) and adsorption capacity (∼100 mg g⁻¹) for Hg(II). The kinetics of the pseudo-second-order model and the mechanisms of electrostatic adsorption, ion exchange, and complex reactions are provided. The proposed closed-cycle strategy can be useful for early, fast, and mobile detection of Hg (II) pollution, followed by its effective removal during water treatment.

β-Blockers (BB) are one of the most commonly prescribed pharmaceuticals used for treating cardiovascular and acute anxiety-related disorders. This class of drugs inhibit β-adrenoceptor signalling and given their growing, widespread use, BB are routinely detected in surface waters at nM concentrations. This is concerning as trace levels of BB impart developmental and reproductive dysfunction in non-target aquatic organisms, with potential for ecological risks. To date, environmental pharmaceutical risks to non-target animals are not part of the monitoring framework due to the lack of bioassays for assessing their biological effects. Behavioral endpoints have the advantage of a systems-level integration of multiple sensory signals and motor responses for toxicity screening; however, they are not currently used for risk assessment of environmental contaminants. The zebrafish (Danio rerio) embryo photomotor response (zfPMR) has been used in high-throughput behavioral screenings for neuroactive drug effects at high, therapeutic concentrations. Our objective here was to examine if we could utilize the zfPMR for screening environmental levels of BB. Embryos were placed into 96-well plates, exposed to chemicals and/or municipal wastewater effluent (MWWE), and their zfPMRs were measured with video-analysis. To specifically target BB, embryos were co-treated with isoproterenol, a β-adrenergic agonist that stimulates the zfPMR, and the inhibition of isoproterenol-induced response was used as a biomarker of BB exposure. Our results reveal that the inhibition of isoproterenol-stimulated zfPMRs can be used as a biosensor capable of detecting BB in the parts-per-billion to parts-per-trillion in water samples, including diluted MWWE. The method developed detects BB in spite of the presence of other neuroactive compounds in water samples. This systems level approach of rapid screening for BB effects provides the most promising evidence to date that behavioral neuromodulation can be potentially applied for environmental effects monitoring of pharmaceuticals.

The ubiquity of pollutants, such as agrochemicals and heavy metals, constitute a serious risk to human health. To evaluate the induction of DNA damage and programmed cell death (PCD), root cells of Allium cepa and Vicia faba were treated with two organophosphate insecticides (OI), fenthion and malathion, and with two heavy metal (HM) salts, nickel nitrate and potassium dichromate. An alkaline variant of the comet assay was performed to identify DNA breaks; the results showed comets in a dose-dependent manner, while higher concentrations induced clouds following exposure to OIs and HMs. Similarly, treatments with higher concentrations of OIs and HMs were analyzed by immunocytochemistry, and several structural characteristics of PCD were observed, including chromatin condensation, cytoplasmic vacuolization, nuclear shrinkage, condensation of the protoplast away from the cell wall, and nuclei fragmentation with apoptotic-like corpse formation. Abiotic stress also caused other features associated with PCD, such as an increase of active caspase-3-like protein, changes in the location of cytochrome C (Cyt C) toward the cytoplasm, and decreases in extracellular signal-regulated protein kinase (ERK) expression. Genotoxicity results setting out an oxidative via of DNA damage and evidence the role of the high affinity of HM and OI by DNA molecule as underlying cause of genotoxic effect. The PCD features observed in root cells of A. cepa and V. faba suggest that PCD takes place through a process that involves ERK inactivation, culminating in Cyt C release and caspase-3-like activation. The sensitivity of both plant models to abiotic stress was clearly demonstrated, validating their role as good biosensors of DNA breakage and PCD induced by environmental stressors.