Ecotoxicological assessment and electrochemical remediation of doxorubicin

Unlocking the potential of bacterioplankton-mediated microcystin degradation and removal: A bibliometric analysis of sustainable water treatment strategies

Microcystins (MCs) constitute a significant threat to human and environmental health, urging the development of effective removal methods for these toxins. In this review, we explore the potential of MC-degrading bacteria as a solution for the removal of MCs from water. The review insights into the mechanisms of action employed by these bacteria, elucidating their ability to degrade and thus remove MCs. After, the review points out the influence of the structural conformation of MCs on their removal, particularly their stability at different water depths within different water bodies. Then, we review the crucial role played by the production of MCs in ensuring the survival and safeguarding of the enzymatic activities of Microcystis cells. This justifies the need for developing effective and sustainable methods for removing MCs from aquatic ecosystems, given their critical ecological function and potential toxicity to humans and animals. Thereafter, challenges and limitations associated with using MC-degrading bacteria in water treatment are discussed, emphasizing the need for further research to optimize the selection of bacterial strains used for MCs biodegradation. The interaction of MCs-degrading bacteria with sediment particles is also crucial for their toxin removal potential and its efficiency. By presenting critical information, this review is a valuable resource for researchers, policymakers, and stakeholders involved in developing sustainable and practical approaches to remove MCs. Our review highlights the potential of various applications of MC-degrading bacteria, including multi-soil-layering (MSL) technologies. It emphasizes the need for ongoing research to optimize the utilization of MC-degrading bacteria in water treatment, ultimately ensuring the safety and quality of water sources. Moreover, this review highlights the value of bibliometric analyses in revealing research gaps and trends, providing detailed insights for further investigations. Specifically, we discuss the importance of employing advanced genomics, especially combining various OMICS approaches to identify and optimize the potential of MCs-degrading bacteria.

Distribution and Risk Assessment of Organophosphate Esters in Agricultural Soils and Plants in the Coastal Areas of South China

Organophosphate esters (OPEs) are frequently used as flame retardants and plasticizers in various commercial products. While initially considered as substitutes for brominated flame retardants, they have faced restrictions in some countries due to their toxic effects on organisms. We collected 37 soil and crop samples in 20 cities along the coast of South China, and OPEs were detected in all of them. Meanwhile, we studied the contamination and potential human health risks of OPEs. In soil samples, the combined concentrations of eight OPEs varied between 74.7 and 410 ng/g, averaging at 255 ng/g. Meanwhile, in plant samples, the collective concentrations of eight OPEs ranged from 202 to 751 ng/g, with an average concentration of 381 ng/g. TDCIPP, TCPP, TCEP, and ToCP were the main OPE compounds in both plant and soil samples. Within the study area, the contaminants showed different spatial distributions. Notably, higher OPEs were found in coastal agricultural soils in Guangdong Province and crops in the Guangxi Zhuang Autonomous Region. The results of an ecological risk assessment show that the farmland soil along the southern coast of China is at high or medium ecological risk. The average non-carcinogenic risk and the carcinogenic risk of OPEs in soil through ingestion and dermal exposure routes are within acceptable levels. Meanwhile, this study found that the dietary intake of OPEs through food is relatively low, but twice as high as other studies, requiring serious attention. The research findings suggest that the human risk assessment indicates potential adverse effects on human health due to OPEs in the soil-plant system along the coast of South China. This study provides a crucial foundation for managing safety risks in agricultural operations involving OPEs.

Electrochemical oxidation diminished toxicity of zearalenone significantly, while reduction increased

Zearalenone (ZEN), one of the most common mycotoxins in cereals, poses a severe health risk to humans. In this study, electrochemical oxidation and reduction degraded ZEN in solution completely within 8 min and 20 min. The structure of ZEN products was elucidated by mass spectrometry (MS), and their toxicity was evaluated by ECOSAR software and cytotoxicity assay. From simulation, electrochemical oxidation products had lower acute and chronic toxicity, and the product at 9.0 V is not harmful (LC50/EC50 greater than 100 mg/L, ChV greater than 10 mg/L). CCK-8 assay further confirmed their less cytotoxicity. To our surprise, LC50, EC50, and ChVs of all electrochemical reduction products were lower than 1 mg/L, and cell viabilities were less than ZEN, meaning the higher toxicity of electrochemical reduction products. On this Basis, electrochemical oxidation was applied in ZEN contaminated wheat with a degradation rate of 92.32 ± 2.37%, indicating its potential to degrade ZEN practically.

Photocatalysis of carbamazepine via activating bisulfite by ultraviolet: Performance, transformation mechanism, and residual toxicity assessment of intermediates products

Carbamazepine (CBZ) as an extensively distributed emerging pollutant has menaced ecological security. The degradation performance of CBZ by UV driven bisulfite process was investigated in this work. The kinetics results indicated that CBZ was high-efficiently degraded by UV/bisulfite following a pseudo first-order kinetic model (K_obs = 0.0925 min^-1). SO₄^•- and •OH were verified as the reactive oxidants by EPR test and the radicals scavenging experiment using MeOH and TBA. SO₄^•- played a dominant role for CBZ degradation. The Density functional theory (DFT) and LC-qTOF-MS/MS clarified that hydroxylation, ketonation, ring opening reaction, and ring contraction were main transformation patterns of CBZ. As to influence factors, CBZ degradation was significantly hindered in presence of CO₃^2-, HPO₄^2- and NOM. Toxicological analysis derived from metabonomics suggested that the remarkable alteration of metabolic profile was triggered by exposure to intermediates mixture. CBZ intermediates interfered in several key metabolic pathways, including pentose phosphate, amino acids, lysine degradation, glycerophospholipid, glutathione, nucleotides and carbohydrate, which was alleviated after UV/bisulfite treatment. This work provided a meaningful support to potential risk of CBZ intermediates products, which shed light on the future application in eliminating drugs using UV /bisulfite.

Advanced Electrodegradation of Doxorubicin in Water Using a 3-D Ti/SnO2 Anode

This study investigated the application of an advanced electrooxidation process with three-dimensional tin oxide deposited onto a titanium plate anode, named 3-D Ti/SnO2, for the degradation and mineralization of one of the most important emerging contaminants with cytostatic properties, doxorubicin (DOX). The anode was synthesized using a commercial Ti plate, with corrosion control in acidic medium, used as a substrate for SnO2 deposition by the spin-coating method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses revealed that porous SnO2 was obtained, and the rutile phase of TiO2 was identified as an intermediary substrate onto the Ti plate. The results of CV analysis allowed us to determine the optimal operating conditions for the electrooxidation process conducted under a constant potential regime, controlled by the electron transfer or the diffusion mechanisms, involving hydroxyl radicals. The determination of UV–VIS spectra, total organic carbon (TOC), and chemical oxygen demand (COD) allowed us to identify the degradation mechanism and pathway of DOX onto the 3-D Ti/SnO2 anode. The effective degradation and mineralization of DOX contained in water by the electrooxidation process with this new 3-D dimensionally stable anode (DSA) was demonstrated in this study.

Synthesis of Copolymers Polyethyleneimine-co-Polyphenylalanine as Gene and Drug Codelivery Carrier

In this study, a series of hyperbranched copolymers polyethyleneimine-co-polyphenylalanine (PEI-co-PPhe) are synthesized by ring-opening polymerization with phenylalanine-N-carboxyanhydride as monomer and PEI-25k as initiator, using as a gene and drug codelivery carrier. Among them, PEI-co-PPhe (1:170) is selected out from transfection efficiency and cytotoxicity tests. Then, doxorubicin-cis-aconitic anhydride (CAD) and BCl2-shRNA (as a therapeutic gene) are coloaded into the PEI-co-PPhe carrier to form PEI-co-PPhe/Bcl2-shRNA/CAD complexes as a codeliver system. When the mass ratio of PEI-co-PPhe:Bcl2-shRNA:CAD is 5:1:1, the codeliver system has the most obvious synergistic therapeutic effect against B16F10 cells. Confirmed by confocal laser scanning microscope and flow cytometry, compared with drug and gene alone, the codeliver complexes can be endocytosed into B16F10 cells efficiently. As a result, the appropriate length of PPhe grafted on PEI will improve the gene transfer efficiency and decrease cytotoxicity, as well as effective codelivery of gene and drug into cancer cells to be a promising codelivery carrier for cancer therapy.

Trends, new insights and perspectives in the treatment of hospital effluents

Recently, investigations of hospital effluent management and treatment have not only interested research groups with acquired experience in the field, but have also attracted the interest of new groups over the world. The most recent literature provides new insights into the occurrence of pharmaceuticals and other contaminants of emerging concern, pathogens, viruses, and antibiotic-resistant bacteria and genes in hospital effluent in various new developing and developed countries. It also provides information on the effective removal of key compounds (mainly antibiotics, analgesics, beta-blockers and chemotherapy drugs) by means of enhanced biological treatments and advanced oxidation processes. The current debate among the scientific community is mainly about the proper treatment to reduce the spread of antibiotic-resistant bacteria and genes and about the feasibility (from a technical and economic point of view) of treatment trains tested at lab and pilot scales.

Degradation mechanism, intermediates and toxicology assessment of tris-(2-chloroisopropyl) phosphate using ultraviolet activated hydrogen peroxide

Organophosphate flame retardants (OPFRs), one kind of emerging flame retardants, have received prevalent attention owing to their ubiquity in aquatic matrices and their characteristics of being refractory to biodegradation. In current research, the degradation mechanism of tris-(2-chloroisopropyl) phosphate (TCPP), one of OPFRs, and its toxicological evaluation using UV-driven hydroxyl radical oxidation were investigated. A pseudo-first order reaction was fitted with an apparent rate constant (K_obs) of 0.1328 min^-1 on transformation of TCPP in the case of CH₂O₂ 0.1 mM, pH 6.6-7.1 and 4.7 mW cm^-2 UV irradiation. High resolution mass spectroscopy analyses identified nine degradation products (eg., C₆H₁₃Cl₂O₄P (m/z 251.0002), C₉H₁₇Cl₂O₅P (m/z 307.0266), C₉H₁₇Cl₂O₆P (m/z 323.0217), C₉H₁₈Cl₃O₅P (m/z 343.0033)) during transformation of TCPP. The removal efficiency dropped by inhibitory effect of natural organic matters and anions, implying that the complete mineralization of TCPP may be difficult in actual water treatment process. The toxicity assessment has shown an decrease in reactive oxygen species (ROS) and apoptosis, membrane potential (MP) elevation of Escherichia coli, and biological molecular function revision (eg., metabolism and DNA biosynthesis), indicating that toxicity of degradation products were conspicuously decreased in comparison with intact TCPP. To sum up, effective detoxification of TCPP can be realized by a UV driving radical-based oxidation, which will provide an alternative safe treatment method to control TCPP in water matrix.

Removal of doxorubicin by magnetic copper phosphate nanoflowers for individual urine source separation

Doxorubicin (DOX) originated from users' urine has been an emerging environmental pollutant due to its significant genotoxicity to mankind. Thus, urine source separation is a potential strategy to isolate DOX at a higher concentration and reduce the burden of downstream wastewater treatment. To develop highly efficient, easy separation and retrievable materials for individual patient to conveniently remove DOX from own urine, magnetic Cu₃(PO₄)₂ nanoflowers were prepared through anchoring amino-functionalized magnetic nanoparticles on the Cu₃(PO₄)₂ nanoflowers. Characterizations revealed the magnetic nanoflowers were spherical in shape with a mean size of 15 μm, and porous and hierarchical in structure. Magnetic nanoparticles located the surface of petals. Multibatch experiments were performed to assess the removal performance of DOX from aqueous solution. The magnetic nanoflowers exhibited excellent removal efficiency of DOX under weakly alkaline condition at ambient temperature. Linear and non-linear analyses were carried out to compare the best fitting kinetics and isotherms. Sorption kinetic data best fitted the pseudo-second order model. The Freundlich isotherm explained equilibrium sorption data with R² = 0.993 higher than that for the Langmuir isotherm. When the pH of synthetic urine was adjusted to weakly alkaline (pH 8.0-9.0), over 95% of DOX (20 mg L^-1) was removed by a little of magnetic nanoflowers (50 mg L^-1) within 5 min. Meanwhile, the magnetic nanoflowers could be easily separated and recovered from the synthetic urine by a magnet. So, for individual urine source separation strategy, the magnetic nanoflower seems to be an efficient, convenient and inexpensive approach to remove DOX from human urine.

Doxorubicin-loaded nanoscale metal–organic framework for tumor-targeting combined chemotherapy and chemodynamic therapy

DMH NPs were prepared and could effectively induce MCF-7 cell death through the combination of chemotherapy and chemodynamic therapy.