Arsenic Compounds Research Articles

Comparison of the potential risk from arsenic exposure when eating fish grown in natural and artificial conditions, using the example of rainbow trout

Introduction. Due to the increasing share of fish and fish products in the human diet, hygienic problems are also increasing, especially with the growing of aquaculture sector. The task of determining the level of arsenic toxicity is becoming extremely important. Although the toxicity mechanisms of inorganic arsenic are generally well understood, the impact of speciation of its other (organic) compounds on the likelihood of carcinogenic and non-carcinogenic effects has been largely unexplored. Material and methods. The objects of study were samples of fillet and caviar of salmon fish – rainbow trout (wild and aquaculture). The quantitative determination of arsenic-containing substances was carried out using high-performance liquid chromatography-mass spectrometry with inductively coupled plasma. The samples were prepared using microwave methods. The risk level was calculated based on recommendations R 2.1.10.3968–23. Results. As the result of this work the information about concentration of arsenic (organic and inorganic compounds) in fillets and caviar of fish from the salmon family - rainbow trout was shown. It has been established that the content of inorganic and organic arsenic compounds practically does not differ, depending of the habitat of trout. The levels of carcinogenic and non-carcinogenic risk of inorganic arsenic were calculated. Limitations. Determination of arsenic concentration was carried out in rainbow trout, which had been grown in natural and artificial conditions. Conclusion. It has been established that inorganic arsenic makes the greatest contribution to the health risk. However, the magnitude of the risk does not exceed the acceptable sanitary and hygienic standards, while the conditions for growing fish have practically no effect on these values.

The mechanism of arsenic behaviour in the soil-plant system and its interaction with biogenic macroelements of plants under conditions of toxic stress

ABSTRACT The mobility of arsenic compounds in the soil-plant system and its interaction with biogenic macroelements K, P, Ca, Mg, Si, S, Na in plants under conditions of toxic stress have been studied. This is illustrated by the wheatgrass Elytrigia repens. It has been established that the root system is responsible for protecting the aerial part of wheatgrass from excess arsenic, and it is of great importance for phytostabilisation of arsenic pollution therefore indicating the increased tolerance of this plant. The intensity of As accumulation in plants depends on its speciation in the soil. Antagonism of the main essential elements (K, P) to the accumulation of As in wheatgrass shoots is observed. It can lead to disruption of metabolic processes in plant cells. It has been shown that changes in the K+/Na + values may lead to violation of osmotic processes in the aerial plant organs and contribute to their degradation not only under salt stress but also under the influence of higher concentrations of As in the plants. In areas intensively contaminated with arsenic, a decrease in the K/Na value in the above-ground organs of wheatgrass can be used as a criterion for the degree of phytotoxicity.

A Tumor Homing Peptide-Linked Arsenic Compound Inhibits Pancreatic Cancer Growth and Enhances the Inhibitory Effect of Gemcitabine

Arsenic trioxide (ATO) has been shown to inhibit pancreatic cancer (PC) cell growth in vitro and to promote the inhibitory effects of gemcitabine (Gem) on PC in vivo. However, the high toxicity of ATO associated with the required high doses and indiscriminate targeting has limited its clinical application. This study aimed to determine whether coupling arsenic to a tumor homing peptide would increase the inhibitory potency against PC cells. The effects of this peptide-linked arsenic compound (PhAs-LHP), the analogous non-targeting arsenic compound (phenylarsine oxide, PAO), and marketed ATO on PC growth were tested in vitro and in a mouse model. The data demonstrated that PhAs-LHP inhibited PC cell growth in vitro more potently, with IC50 values 10 times lower than ATO. Like ATO, PhAs-LHP induced cell death and cell cycle arrest. This cytotoxic effect of PhAs-LHP was mediated via a macropinocytosis-linked uptake pathway as amiloride (a macropinocytosis inhibitor) reduced the inhibitory effect of PhAs-LHP. More importantly, PhAs-LHP inhibited PC growth in mice and enhanced the inhibitory effect of Gem on PC growth at 2 times lower molar concentration than PAO. These results indicate that PhAs-LHP inhibited PC more potently than ATO/PAO and suggest a potential clinical use for the combination of Gem with the peptide-linked arsenic compound for the treatment of pancreatic cancer.

Biotransformations of arsenic in marine sediments across marginal slope to hadal zone

Arsenic compounds are accumulating in deep ocean, but their ecological impacts on deep-sea ecosystem remain elusive. We studied 32 sediment cores (101 layers for metagenomes, along with 41 global reference sediment metagenomes) collected from the South China Sea and the Mariana Trench (MT), characterized with high arsenic accumulation in MT. In these metagenomes we revealed a significantly positive correlation between relative abundance of arsenite methyltransferase gene (arsM) and sampling depth, which suggests that arsenic methylation is the most prevalent arsenic biotransformation process in the deep sea. Lower relative abundance of arsenic efflux gene, compared with arsM, indicates that microbes in deep-sea sediments were prone to methylate arsenite and retain it rather than efflux it. Phylogenetic analysis identified seven clades of ArsM proteins, including two new clades derived primarily from deep-sea microorganisms. Five metagenome-assembled genomes containing aioA for arsenite oxidation also harbor carbon fixation genes in the deep-sea sediment layers, suggesting previously unnoticed contribution of arsenite-oxidizing autotrophic bacteria to the carbon cycle. Therefore, deep-sea microorganisms adopt different detoxification and transformation strategies in response to arsenic compounds, which renews our understanding of arsenic in their ecological impacts and potential contribution in deep ocean.

New insights into zinc alleviating renal toxicity of arsenic-exposed carp (Cyprinus carpio) through YAP-TFR/ROS signaling pathway

Environmental pollution caused by arsenic or its compounds is called arsenic pollution. Arsenic pollution mainly comes from people mining and smelting arsenic compounds. In addition, arsenic compounds' widespread use and production of arsenic-containing pesticides, arsenic-rich water used to irrigate farms, or high arsenic levels in foods caused by coal burning are all sources of arsenic contamination. Arsenic contamination poses a significant threat to global public health. It is reported that exposure to arsenic can induce severe renal injury. However, the underlying mechanism needs to be clarified. In this study, the arsenic exposure model in vivo and in vitro was used to explore the mechanism of arsenic-induced renal injury, especially the role of ferroptosis and its regulatory mechanism, and then to evaluate its anti-pollution effect by supplementing zinc. The results showed that arsenic significantly induced ferroptosis, characterized by up-regulating the expression of YAP and TFR in kidney and CIK cells and then increasing the levels of Fe2+ and ROS, lipid peroxidation, and iron metabolism. Microscopic observation revealed the shrinkage of mitochondria and the increase in membrane density. In addition, molecular docking and inhibitor experiments further confirmed that arsenic is involved in the process of ferroptosis by activating YAP and TFR. These results clarify the harmful effects of arsenic on carp kidneys and its mechanism and highlight the critical interactions between the YAP-TFR pathway, ROS, and ferroptosis. Importantly, this study found that zinc can reduce ferroptosis caused by the arsenic-activated YAP-TFR pathway by inhibiting YAP activation and lipid peroxidation.

Hybrid-genome sequence analysis of Enterobacter cloacae FACU and morphological characterization: insights into a highly arsenic-resistant strain.

Many organisms have adapted to survive in environments with high levels of arsenic (As), a naturally occurring metalloid with various oxidation states and a common element in human activities. These organisms employ diverse mechanisms to resist the harmful effects of arsenic compounds. Ten arsenic-resistant bacteria were isolated from contaminated wastewater in this study. The most efficient bacterial isolate able to resist 15,000ppm Na2HAsO4·7H2O was identified using the 16S rRNA gene and whole genome analysis as Enterobacter cloacae FACU. The arsenic E. cloacae FACU biosorption capability was analyzed. To further unravel the genetic determinants of As stress resistance, the whole genome sequence of E. cloacae FACU was performed. The FACU complete genome sequence consists of one chromosome (5.7Mb) and two plasmids, pENCL 1 and pENCL 2 (755,058 and 1155666bp, respectively). 7152 CDSs were identified in the E. cloacae FACU genome. The genome consists of 130 genes for tRNA and 21 for rRNAs. The average G + C content was found to be 54%. Sequencing analysis annotated 58 genes related to resistance to many heavy metals, including 16 genes involved in arsenic efflux transporter and arsenic reduction (five arsRDABC genes) and 42 genes related to lead, zinc, mercury, nickel, silver, copper, cadmium and chromium in FACU. Scanning electron microscopy (SEM) confirmed the difference between the morphological responses of the As-treated FACU compared to the control strain. The study highlights the genes involved in the mechanism of As stress resistance, metabolic pathways, and potential activity of E. cloacae FACU at the genetic level.

Hierarchical graphene oxide/nano-pyramidal stainless-steel on nickel foam substrate: A flexible electrochemical sensor for arsenic compound detection

The organoarsenic compound roxarsone (ROX) is added to chicken feed to enhance nutritional value. Although organic arsenic is generally less harmful than inorganic arsenic, concerns have arisen about its potential to transform into inorganic forms when excreted in animal waste, raising environmental and human health concerns. The potential dangers of long-term ROX exposure require reliable methods for the detection of the target analyte. In the current study, fabricated nanoscale graphene oxide (GO)/stainless steel (SS) pyramidal structures on nickel foam (NF) is used as an electrode in the electrochemical detection of ROX. The proposed sensor was shown to outperform existing devices in terms of electrochemical activity, resulting in a wider linear range of detection for ROX (0.05–83.15 µM) and lower detection limit (LOD) (0.006 µM). Further, real sample analysis on water and meat samples confirmed the feasibility of the proposed GO/SS/NF sensor for the real-time detection of ROX in real-world applications. This research provides evidence to support the development of heterojunctions to improve ion transport channels and surface-active sites to promote ion mobility to enhance electrochemical responses.

Arsenic Adsorption in Subunits of Metal‐Organic Frameworks—A DFT Approach to Assist Water Treatment

AbstractThe removal of arsenic compounds from water is classified as an urgent concern by the World Health Organization, since many of these species are hazardous to human health. However, the conventional water treatments are not able to extract them, which makes the development of new methodologies of arsenic removal noteworthy. The application of metal‐organic frameworks (MOFs) as adsorbents to attend this purpose is very promising, because these materials can be intelligently built for the desired application. In this work, the performance of common subunits usually found in MOFs were individually evaluated for the adsorption of some arsenic species through computer simulations based on density functional theory (DFT). Thus, important information at molecular level was obtained, which can assist the design of an optimized adsorbent. Three factors were identified to strengthen the adsorption: ionic coordinate bond, hydrogen bonds, and cycle formation. Furthermore, the evaluated subunits showed to be proper for the removal of HAsO2, once the change in the Gibbs free energy was up to −30.8 kcal mol−1. The comparison with possible coexistent species showed that Cl−, , and can interfere with adsorptive process depending on the MOF composition and on the arsenic species to be removed from water.

P01-22 Anticancer effect of arsenic compounds on apoptosis in oral cavity cancer cells

P01-22 Anticancer effect of arsenic compounds on apoptosis in oral cavity cancer cells

In-situ activated arsenic-molybdenum dual-prodrug nanocomplexes for glutathione-depletion enhanced photothermal/chemotherapy against triple-negative breast cancer

Arsenic trioxide, a traditional chemotherapeutic agent, has limitations in clinical application due to its nonspecific delivery and severe systemic toxicity. To address this challenge, we have capitalized on the promising potential of molybdenum-based materials for tumor diagnosis and treatment. We developed a novel multifunctional arsenic-molybdenum dual-prodrug nanocomposite delivery system (AsMo-NCM) by integrating arsenic compounds with molybdenum compounds. This system leverages elevated glutathione (GSH) levels within tumors for specific activation. Within the tumor microenvironment, the system converts Mo(VI) to the more active Mo(V), enabling combined photothermal therapy and photoacoustic imaging for comprehensive diagnosis and treatment. Furthermore, low-toxicity arsenic(V) is converted into highly toxic trivalent arsenic within the high-GSH tumor microenvironment, thereby enhancing tumor cell apoptosis, reducing toxicity to normal tissues, and synergistically improving treatment outcomes. In addition, AsMo-NCM can be biodegraded and rapidly excreted, reducing concerns about their long-term presence and possible toxic effects. The combination of these approaches maximizes GSH depletion, thereby enhancing the synergistic photothermal/chemotherapy effect of AsMo-NCM for precise and effective tumor treatment, thus offering promising prospects for cancer therapy.

Structural stability and metallization of orpiment at high pressure

Binary arsenic sulfide compounds have garnered significant attention owing to their wide-ranging physical properties and promising potential in the domains of electronics and optoelectronics. As a naturally abundant and historically significant semiconductor mineral, orpiment (crystalline As2S3) has encountered limited utilization in the realm of optoelectronics due to its considerable bandgap width. For orpiment with its quasi-two-dimensional layered structure, pressure is one of the most effective methods to regulate its crystal structure and physical properties. In this work, the structural behavior, optical and electrical properties of orpiment under high pressure have been investigated systematically utilizing a combination of experimental methods and theoretical calculations. The monoclinic structure of orpiment is stable up to 48 GPa without structural phase transitions involving changes in the space group occurred. The noticeable changes of lattice parameters, axial ratios, and interatomic distances above 20 GPa are ascribed to a transformation from a two-dimensional layered structure to a quasi-three-dimensional crystal framework. Continuous lattice contraction upon compression is accompanied by gradual bandgap narrowing, which leads to metallization of orpiment. The pressure-induced metallization of orpiment occurs above 40 GPa. The structural behavior, optical and electrical properties of orpiment at high pressure exhibit reversible hysteresis upon pressure release. This study offers a high-pressure approach for modulating crystal structure and physical properties of orpiment to expand its potential applications in the fields of electronics and optoelectronics.

First-Principles Studies of the Electronic and Optical Properties of Two-Dimensional Arsenic-Phosphorus (2D As-P) Compounds.

In this work, we propose the construction of a two-dimensional system based on the stable phases previously reported for the 2D arsenic and phosphorus compounds, with hexagonal and orthorhombic symmetries. Therefore, we have modeled one hexagonal and three possible orthorhombic structures. To ensure the dynamical stability, we performed phonon spectra calculations for each system. We found that all phases are dynamically stable. To ensure the thermodynamic and mechanical stabilities, we have calculated cohesive energies and elastic constants. Our results show that the criteria for the stabilities are all fulfilled. For these stable structures, we computed the electronic and optical properties from first-principles studies based on density functional theory. The computation of electronic band gaps was performed by using the GW approximation to overcome the underestimation of the results obtained from standard DFT approaches. To study the optical properties, we have computed the dielectric function imaginary part within the BSE approach, which takes into account the excitonic effects and allows us to calculate the exciton binding energies of each system. The study was complemented by the computation of the absorption coefficient. From our calculations, it can be established that the 2D As-P systems are good candidates for several technological applications.

Tissue Distribution and Toxicological Risk Assessment of Mercury and Other Elements in Northern Populations of Wolverine (Gulo gulo)

Wolverines are facultative scavengers that feed near the top of terrestrial food chains. We characterized concentrations of mercury and other trace elements in tissues of wolverine from a broad geographic area, representing much of their contemporary distribution in northwestern North America. We obtained tissues from 504 wolverines, from which mercury was measured on muscle (n = 448), kidney (n = 222), liver (n = 148), hair (n = 130), and brain (n = 52). In addition, methylmercury, seven trace elements (arsenic, cadmium, chromium, cobalt, lead, nickel, selenium), and arsenic compounds were measured on a subset of samples. Concentrations of mercury and other trace elements varied between tissues and were generally highest in kidney compared to brain, liver and muscle. Mercury was predominately as methylmercury in brain and muscle, but largely as inorganic mercury in liver and kidney. Mercury concentrations of hair were moderately correlated with those of internal tissues (Pearson r = 0.51–0.75, p ≤ 0.004), making hair a good non-lethal indicator of broad spatial or temporal differences in mercury exposure to wolverine. Arsenobetaine was the dominant arsenic compound identified in tissues, and arsenite, arsenocholine and dimethylarsinic acid were also detected. A preliminary risk assessment suggested the cadmium, lead, mercury, and selenium concentrations in our sample of wolverines were not likely to pose a risk of overt toxicological effects. This study generated a comprehensive dataset on mercury and other trace elements in wolverine, which will support future contaminants study of this northern terrestrial carnivore.

Protective effects of Butylated Hydroxytoluene (BHT) against sodium Arsenite (NaAsO2) - Induced hepatotoxicity in Wistar Rats

One of the major environmental contaminants that can be found on a global scale is arsenic. Sodium arsenite (NaAsO2) is one of the compounds of arsenic which is considered very toxic. Long term exposure to NaAsO2 can cause chemical complications in various organs of the body such as the liver, kidney, testes and brain tissues. Butylated hydroxytoluene (BHT) is an antioxidant that can serve as an antitoxic effect. NaAsO2. In this topic, we examined the chemo-protective effect of BHT on NaAsO2 induced hepatotoxicity in male Wistar rats. Wistar rats (n=42, +120g) were randomly grouped into seven treatment groups: of 7 animals each Control 1(corn oil); Control 2(distilled water); NaAsO2 alone (2.5mg/kg). BHT alone (25 mg/kg); BHT only (25mg/kg); BHT+ NaAsO2 (25mg/kg + 2.5/kg), and BHT+ NaAsO2 (2.5g/kg + 50 mg/kg) and treated for 14 days. Markers of liver functions, inflammation, oxidative stress and antioxidant profile of liver were assayed spectrophotometrically. Our results showed that exposure to NaAsO2 resulted in dramatic increase in the levels of AST, ALT and ALP activity Furthermore, NaAsO2 increased the concentration of oxidative stress markers such as xanthine oxidase (XO) and lipid peroxidation (MDA) and inflammatory markers such as myeloperoxidase (MPO) and nitric oxide (NO) with a concomitant decrease in antioxidant markers such as superoxide dismutase (SOD). Glutathione-S-transferase (GST), and catalase. However, the co-exposure of rats to both BHT and NaAsO2 can result in significant decrease the parameters above. In conclusion, exposure of rats to NaAsO2 causes increased inflammatory and oxidative stress signals, but these harmful effects can be ameliorated by administration of antioxidants such as BHT as confirmed by this research.

Arsenic induces hepatotoxicity in chickens via PANoptosis pathway

Environmental pollution caused by arsenic or its compounds is called arsenic pollution. Arsenic pollution mainly comes from people's mining and smelting of arsenic compounds. In addition, the widespread use of arsenic compounds, such as the use and production of arsenic-containing pesticides, is also a source of arsenic contamination. Arsenic contamination leads to an increased risk of arsenic exposure, and the multi-organ toxicity induced by arsenic exposure is a global health problem. As a non-mammalian vertebrate with high nutrient levels, chickens readily absorb and accumulate arsenic from their food. Relevant studies have shown that arsenic exposure induces hepatotoxicity in chickens, and there has been a steady stream of research into the specific mechanisms involved. PANoptosis, a newly discovered and unique mode of programmed cell death (PCD) characterized by both apoptosis, cellular pyroptosis, and necroptosis. There are no studies to indicate whether chicken liver toxicity due to arsenic is associated with PANoptosis. Therefore, we established chicken animal models and chicken primary hepatocyte models exposed to different arsenic concentrations to dissect the role and mechanism of PANoptosis in arsenic exposure-induced hepatotoxicity in chickens. Our histopathological results showed that arsenic treatment caused dose-dependent damage to chicken liver structure. Meanwhile, different doses of arsenic treatment groups caused significant up-regulation of the protein level of ZBP1, a key factor of PANoptosis. And then consequently triggered the abnormal gene and protein expression levels of apoptosis-associated factors (Caspase-8, Caspase-7, Caspase-3), cellular pyroptosis-associated factors (NLRP3, ASC, GSDMD) and necroptosis-associated factors (RIPK1, RIPK3, MLKL). In conclusion, our study revealed that PANoptosis is involved in arsenic-induced chicken hepatotoxicity. Our findings provide a new perspective on the pathogenesis of arsenic exposure-induced hepatotoxicity in chickens.

Adsorption of Cu(II) and Zn(II) onto ZrO2–SiO2 composite: Characteristics, mechanism and application in wastewater treatment

The presented paper describes a perspective methodology of hazardous post-production wastewater treatment focused on recovering selected metal ions species, mainly copper, zinc, and arsenic. The idea included the design of multifunctional adsorbents composed of zirconia and silica, their physicochemical evaluations, and verification tests in the adsorption process performed using model wastewaters. The proposed synthesis protocol allowed to obtain the materials with unique structural and physicochemical properties, including well-developed surface area (ABET = 398 m2∙g−1), as well as specific surface nature. It was confirmed by the results of energy dispersive X-ray, X-ray fluorescence and Fourier transform infrared spectroscopy analyses. Furthermore, by analysing the batch experiments, optimal process parameters for recovering the analyzed metal ions were established as follows: T = 313 K, pH = 5, S:L ratio = 6.67 mg:cm3, and t = 120 min. It was found that the performed removal of selected metal ion species followed pseudo-second-order kinetic and Langmuir isotherm models, and the estimated sorption capacity of the designed material was 23.5 mg∙g−1 and 12.4 mg∙g−1 for Cu(II) and Zn(II) ions, respectively. The results indicate that it is possible to separate arsenic compounds from copper and zinc ions with efficiencies of 98.9 % and 99.5 % respectively.

Impact of arsenic and PAHs compound contamination on microorganisms in coking sites: From a community to individual perspective

Arsenic (As) and polycyclic aromatic hydrocarbons (PAHs) are highly toxic, carcinogenic and teratogenic, and are commonly found in soils of industrial sites such as coking plants. They exert environmental stresses on soil microorganisms, but their compounding effects have not been systematically studied. Exploring the effects of compound contamination on microbial communities, species and genes is important for revealing the ecological damage caused by compound contamination and offering scientific insights into soil remediation strategies. In this study, we selected soil samples from 0 to 100 cm depth of a coking site with As, PAHs and compound contamination. We investigated the compound effects of As and PAHs on microbial communities by combining high-throughput sequencing, metagenomic sequencing and genome assembly. Compared with single contamination, compound contamination reduced the microbial community diversity by 10.68%–12.07% and reduced the community richness by 8.39%–18.61%. The compound contamination decreased 32.41%–46.02% of microbial PAHs metabolic gene abundance, 11.36%–19.25% of cell membrane transport gene abundance and 12.62%–57.77% of cell motility gene abundance. Xanthobacteraceae, the biomarker for compound contaminated soils, harbors arsenic reduction genes and PAHs degradation pathways of naphthalene, benzo [a]pyrene, fluorene, anthracene, and phenanthrene. Its broad metabolic capabilities, encompassing sulfur metabolism and quorum sensing, facilitate the acquisition of energy and nutrients, thereby conferring ecological niche advantages in compound contaminated environments. This study underscores the significant impacts of As and PAHs on the composition and function of microbial communities, thereby enriching our understanding of their combined effects and providing insights for the remediation of compound contaminated sites.

Metabolome analysis revealed the critical role of betaine for arsenobetaine biosynthesis in the marine medaka (Oryzias melastigma)

Arsenobetaine (AsB), a non-toxic arsenic (As) compound found in marine fish, structurally resembles betaine (GB), a common methyl donor in organisms. This study investigates the potential role of GB in AsB synthesis in marine medaka (Oryzias melastigma) using metabolomic analysis. Dietary exposure to arsenate (As(V)) and varying GB concentrations (0.05% and 0.1% in diets) increased total As and AsB bioaccumulation, particularly in marine medaka muscle. Metabolomic analysis revealed that GB played a crucial role in promoting up-regulation in methylthioadenosine (MTA) by modulating the methionine cycle and down-regulation in glutathione (GSH) by modulating the glutathione cycle. Methionine metabolism and GSH, potentially binding again to exogenous GB, could synchronously produce more non-toxic AsB. Combining verification experiments of differential metabolites of Escherichia coli in vitro, GB, GSH, S-adenosylmethionine (SAM), and arsenocholine (AsC) entered methionine and glutathione metabolism pathways to generate more AsB. These findings underscore the GB's crucial regulatory role in modulating the synthesis of AsB. This study provides vital insights into the interplay between the structural analogs GB and AsB, offering specific strategies to enhance the detoxification mechanisms of marine fish in As-contaminated environments.

Arsenate Stabilization via Dynamic Covalent Chemistry

AbstractWe report the synthesis of arsenic heterocycles derived from saccharides 2–4 and AsCl3. Compounds 5 and 6 are stable in aqueous solutions, DMSO, or methanolic solutions. However, NMR and HPLC studies revealed that intramolecular trans‐esterification processes leads to dynamic equilibria. Theoretical studies revealed that three arsenates and two arsoranes participate in these intramolecular equilibria and account for the experimental spectroscopy and HPLC results. Through the correlation between the experimental and theoretical 13C NMR spectra, we proposed the speciation of arsenic Compounds 5 and 6. Moreover, experimental and theoretical IR spectra demonstrated that arsenates 5 A and 6 A predominate in the solid state. QTAIM studies were performed to explain the chemical shifts in the 13C NMR spectra. Biological studies suggest that the structural flexibility of Compounds 5 and 6 increase the cytotoxic and antiproliferative activities of these compounds.

Mo-doped Co LDHs as Raman enhanced substrate for detection of roxarsine

BackgroundRoxarsone (ROX) is widely used as a feed additive, which is indigestible after ingestion by poultry, and most of it can only be excreted into the natural environment and degraded into highly toxic and carcinogenic inorganic arsenic compounds, which pose a hazard to the ecosystem and human health. However, for roxarsone, traditional detection methods require complex and time-consuming procedures, so it is urgent to find a new fast detection method for detection of ROX. ResultsIn this work, we developed a novel Raman enhancement material and utilized the Surface-enhanced Raman scattering (SERS) technique to achieve rapid and sensitive detection of roxarsone. Specifically, Mo-doped cobalt layered double hydroxides (Co-LDHs) semiconductor material (abbreviated as CMM-100) was prepared by a simple method of using ion-assisted MOF etching. Under laser excitation at a wavelength of 532 nm, the CMM-100 showed excellent SERS property to various organic dye molecules such as methylene blue (MB), Toluidine Blue(TB), and Crystal Violet (CV). Especially, an enhancement factor (EF) of 1.4 × 106 was achieved for MB. Compared with the traditional method, this work utilized the fast and non-destructive SERS technology, which achieved a rapid detection of ROX. The detection limit was as low as 9.73 × 10−10 M, and the detection range was from 10−9 M to 10−3 M. SignificanceIn this work, SERS technology was adopted for the rapid and sensitive detection of ROX. This study provides a Raman-enhanced substrate named CMMs for detection of food additives, pesticides, biomolecules, etc., which also broadens the application areas of SERS materials.