Copper Sulfide Nanoparticles Research Articles

Copper sulfide nanoparticles on titanium dioxide (TiO2) nanoflakes: A new hybrid asymmetrical Faradaic supercapacitors with high energy density and superior lifespan

In this research work, we have prepared nanocomposites of copper sulfide (CuS) nanoparticles (NPs) with titanium dioxide (TiO2) nanoflakes, with varying contents of CuS, via combined chemical precipitation and sol-gel methods. The effects of CuS concentration on the structural, morphological and electrochemical properties of TiO2/CuS nanocomposites for hybrid asymmetric Faradaic supercapacitors was studied for the first time. Electrochemical studies were carried out by using CV, CD, and EIS measurements in a three/two-electrode setups for both capacitive and practical aspects. When serving as an electrode material for the supercapacitors in three-electrode measurements, all the samples demonstrated a capacitive nature with a Faradaic charge storage mechanism due to the prominent redox peaks originating from their CV and voltage plateau in the CD profile. The optimized electrode ST-3 revealed the highest energy storage performance (capacitance: 853 F g−1) with low charge transfer and solution resistance compared with other electrodes (CuS: 440 F g−1, TiO2: 326 F g−1, ST-1: 535 F g−1, ST-5: 672 F g−1) at 1 Ag−1 with the superior rate capability. The ST-3//AC//KOH ASC displayed a high capacitance of 226.5 F g−1 and 80.2 F g−1 at the discharge current was prolonged from 1 to 5 A g−1 after an optimized voltage of 1.8 V in a two-electrode setup. Interestingly, an outstanding energy density of 68.4 W h kg−1 was achieved at a high-power density of 8150 W kg−1 at a discharge current of 1 and 5 A g−1, with the descent durability of 87 % at a high discharge current of 6 A g−1 when recycled for a large number of 25,000 cycles. These outstanding features highlight an appealing, low-cost, simple, and green route to synthesize other transition metal sulfides for the next-generation electronic devices.

Cysteine-Mediated Green Synthesis of Copper Sulphide Nanoparticles: Biocompatibility Studies and Characterization as Counter Electrodes.

A one-pot green method for aqueous synthesis of fluorescent copper sulphide nanoparticles (NPs) was developed. The reaction was carried out in borax–citrate buffer at physiological pH, 37 °C, aerobic conditions and using Cu (II) and the biological thiol cysteine. NPs exhibit green fluorescence with a peak at 520 nm when excited at 410 nm and an absorbance peak at 410 nm. A size between 8–12 nm was determined by dynamic light scattering and transmission electron microscopy. An interplanar atomic distance of (3.5 ± 0.1) Å and a hexagonal chalcocite crystalline structure (βCh) of Cu2S NPs were also determined (HR-TEM). Furthermore, FTIR analyses revealed a Cu-S bond and the presence of organic molecules on NPs. Regarding toxicity, fluorescent Cu2S NPs display high biocompatibility when tested in cell lines and bacterial strains. Electrocatalytic activity of Cu2S NPs as counter electrodes was evaluated, and the best value of charge transfer resistance (Rct) was obtained with FTO/Cu2S (four layers). Consequently, the performance of biomimetic Cu2S NPs as counter electrodes in photovoltaic devices constructed using different sensitizers (ruthenium dye or CdTe NPs) and electrolytes (S2−/Sn2− or I−/I3−) was successfully checked. Altogether, novel characteristics of copper sulfide NPs such as green, simple, and inexpensive production, spectroscopic properties, high biocompatibility, and particularly their electrochemical performance, validate its use in different biotechnological applications.

Copper sulfide engineered covalent organic frameworks for pH-responsive chemo/photothermal/chemodynamic synergistic therapy against cancer

Developing nanomedicines with high-performance is a promising therapeutic strategy for cancer treatment. Herein, a multifunctional nanoplatform (CuS@COFs-BSA-FA/DOX) based on copper sulfide nanoparticles engineered covalent organic frameworks (CuS@COFs) has been established for synergistic photothermal therapy (PTT), chemotherapy and chemodynamic therapy (CDT). The high photothermal effect and excellent Fenton-like catalytic activity enabled CuS@COFs to generate a new minimally invasive PTT/CDT synergistic therapy. Moreover, with the pH-dependent fluorescence behavior and the inherited mesoporous structure, the nanocomposites can also be utilized as fluorescent probes for cancer cell imaging and drug-delivery carriers to encapsulate the chemotherapeutic agent, DOX. The densely coated PEI and BSA-FA layers on the surface of CuS@COFs not only increased the cancer-targeting efficiency but also prevented the nonspecific release of DOX from CuS@COFs. The acid tumor microenvironment and near-infrared light triggered the release of DOX for chemotherapy, which simultaneously augmented the CDT efficiency of CuS@COFs. Notably, the localized hyperthermia induced by PTT can further improve the CDT efficiency of the nanoplatform, leading to a synergistic PTT/chemotherapy/CDT effect. The nanoplatform possessed the capability of cancer cell-targeted imaging and achieved better therapeutic efficacy with negligible systemic toxicity both in vitro and in vivo. Our work opens up a powerful avenue for developing multifunctional COFs-based theranostic platform and shows strong potential in practical applications.

Bacterial outer membrane vesicle-templated biomimetic nanoparticles for synergistic photothermo-immunotherapy

A critical challenge in photothermal therapy (PTT) remains in establishing systemic antitumor therapeutics against both primary and distant tumors, due to unsatisfactory photothermal conversion efficiency, insufficient tumor accumulation, and limited antitumor immunity of PTT agents. Here, outer membrane vesicles (OMVs) derived from Escherichia coli Nissle 1917 are explored as the nanoreactors to fabricate biomimetic copper sulfide nanoparticles (CuS-OMVs) for systemic photothermo-immunotherapeutic synergy. CuS-OMVs exhibit high photothermal conversion efficacy, good photostability, and considerable tumor targeting capacity, which thus cause apparent hyperthermia and subsequent distinct suppression of tumor cells at tumors upon second near-infrared (NIR-II) light irradiation. The CuS-OMVs-induced cytotoxicity elicits strong immunogenic cell death (ICD) of tumor cells, and facilitates dendritic cell (DC) maturation and consequent CD8+ T cell activation. Moreover, CuS-OMVs themselves are found to behave as immune adjuvants to promote DC maturation, and simultaneously repolarize M2-like tumor-associated macrophages (TAMs) into M1-like phenotype to reshape immunosuppressive tumor microenvironment. CuS-OMVs thus yield potent antitumor efficacies against both primary tumors and untreated distant tumors upon NIR-II light irradiation. This study provides insights into biomimetic nanomaterials for highly efficient photothermo-immunotherapy toward potent cancer therapy.

NIR-Ⅱ window Triple-mode antibacterial Nanoplatform: Cationic Copper sulfide nanoparticles combined vancomycin for synergistic bacteria eradication

The widespread use of antibiotics leads to the increasing drug resistance of bacteria and poses a threat to human health. Therefore, there is an urgent need to develop new antibacterial strategies. Herein, based on the good photothermal properties of Copper sulfide (CuS) nanoparticles under near infrared (NIR) laser, we developed a NIR-Ⅱ window triple-mode synergetic antibacterial cCuS (cationic CuS) @Vancomycin (Van) nanoplatform. In the proposed nanoplatform, the positive charge on the surface makes cCuS@Van nanoplatform show better bacterial uptake and membrane damage; vancomycin induces chemical sterilization and provides a targeting effect to the nanoplatform; combined with the strong photothermal effect and deep tissue penetration at the excitation of 1064 nm laser, cCuS@Van nanoplatform can effectively kill bacterial. The photothermal conversion efficiency of the nanoplatform can reach 49.12 % and in vitro experiments show a sterilizing rate of more than 99.5 % to staphylococcus aureus (S. aureus) at the concentration of 3.0 μM, which also demonstrated the synergistic effect of cCuS@Van nanoplatform. In addition, low cytotoxicity to human cells conforms the good biocompatibility of the as-prepared cCuS@Van nanoplatform, which endows it a good application prospect in the field of antibacterial, such as wound healing and implant sterilization.

Periplasmic Bacterial Biomineralization of Copper Sulfide Nanoparticles.

Metal sulfides are a common group of extracellular bacterial biominerals. However, only a few cases of intracellular biomineralization are reported in this group, mostly limited to greigite (Fe3S4) in magnetotactic bacteria. Here, a previously unknown periplasmic biomineralization of copper sulfide produced by the magnetotactic bacterium Desulfamplus magnetovallimortis strain BW‐1, a species known to mineralize greigite (Fe3S4) and magnetite (Fe3O4) in the cytoplasm is reported. BW‐1 produces hundreds of spherical nanoparticles, composed of 1–2 nm substructures of a poorly crystalline hexagonal copper sulfide structure that remains in a thermodynamically unstable state. The particles appear to be surrounded by an organic matrix as found from staining and electron microscopy inspection. Differential proteomics suggests that periplasmic proteins, such as a DegP‐like protein and a heavy metal‐binding protein, could be involved in this biomineralization process. The unexpected periplasmic formation of copper sulfide nanoparticles in BW‐1 reveals previously unknown possibilities for intracellular biomineralization that involves intriguing biological control and holds promise for biological metal recovery in times of copper shortage.

Fabrication of hygroscopic photothermal fibroin-based aerogels for dehumidification and solar-driven water harvesting

The high-humidity environment will make people uncomfortable and even easily causes inconvenience to people's health. Thus, various chemical or biological desiccants and air conditioners are applied for air dehumidification. However, how to recycle water resources in the process of efficient dehumidification is a meaningful problem to be solved. In the present work, solar-powered hygroscopic photothermal fibroin-based aerogels for indoor dehumidification and water harvesting were fabricated. Briefly, copper sulfide nanoparticles (CuSNPs) were synthesized using silk fibroin (SF) chains as templates, and the aerogel of SF/CuSNPs composite was obtained by freeze-drying. Subsequently, coating of hydrophilic carboxymethyl chitosan (CMCS) and calcium chloride on the photothermal aerogel was performed for moisture absorption and water recovery from the environment. The CMCS-Ca@SF aerogel exhibits encouraging water uptakes of 1.35 g/g at 90 % relative humidity (RH) for 12 h. Meanwhile, most of the absorbed water from the composite aerogel can be rapidly released within 1 h under 4-sun irradiation due to the photothermal effects of CuSNPs. The hygroscopic aerogel efficiently reduces the humidity in enclosed space and can potentially be applied for outdoor atmospheric water harvesting. Besides, the excellent antibacterial capacity endows the hygroscopic aerogel with long-term storage stability even in a high-humidity environment. This work provides an alternative to developing a convenient, effective hygroscopic aerogel for indoor dehumidification and atmospheric water harvesting.

Poly-β-Cyclodextrin-coated neodymium-containing copper sulphide nanoparticles as an effective anticancer drug carrier

This study aims at tuning the properties of the nanoparticles by incorporating neodymium, exploring the sustained release of drug, and the anticancer activity on breast cancer cells. The crystal characteristics of NdCuS2 nanoparticles are analysed using X-ray diffraction. The morphology and size of the nanoparticles were characterised using Transmission Electron Microscope and particle size analyser. The rate of release of the encapsulated camptothecin and anticancer effects on breast cancer cells are investigated. The nanoparticles are rod-shaped, 132 ± 8 nm long and 27 ± 7 nm wide. The band gap of the nanoparticles is 4.85 eV. The drug encapsulation efficiency is 94.76% (w/w). The drug is released in a sustained manner, over a period of 180 h. The cytotoxicity of the camptothecin-loaded NPs is examined on MDA-MB-231 cells and the IC50 is 4.39 µg mL−1. The NdCuS2 nanoparticles are promising as theranostic agents considering their material characteristics and anticancer activity.

GOx-Functionalized Platelet Membranes-Camouflaging Nanoreactors for Enhanced Multimodal Tumor Treatment.

BackgroundGlucose oxidase (GOx)-based starvation therapy is a new cancer treatment strategy. However, the characteristics such as limited curative effect and hypoxic tumor environment hinder its further application seriously.MethodsHerein, doxorubicin (DOX) loaded in hollow mesoporous copper sulfide (HMCuS) nanoparticles assembled with manganese dioxide (HMMD) as nanoshell was prepared. We developed a targeted enhanced cancer treatment method to camouflage HMMD by GOx-functionalized platelet (PLT) membranes (HMMD@PG).ResultsGOx can be specially transported to the tumor site with PLT membrane for effective starvation treatment. Glucose and oxygen (O2) in the tumor were converted to H2O2 under the catalysis of GOx. HMMD can catalyze H2O2 to produce O2 and consume glutathione (GSH) in time, which regulates the tumor microenvironment (TME) and improves the adverse conditions of anti-tumor. In addition, DOX encapsulated in HMCuS-MnO2 release was accelerated from the nanoparticles after the “gatekeeper” MnO2 is consumed. The study of anti-tumor mechanism shows that the remarkable tumor suppressive ability of HMMD@PG comes from the three peaks synergy of starvation treatment, photothermal treatment (PTT), and chemotherapy. This nanoplatform disguised by PLT membrane has significant tumor inhibition ability, good biocompatibility and almost has no side effects in main organs.ConclusionThis work broadens the application mode of GOx and shows the new development of a multi-mode collaborative processing system of nanoplatforms based on cell membrane camouflage.

Combined Strategy of Wound Healing Using Thermo-Sensitive PNIPAAm Hydrogel and CS/PVA Membranes: Development and In-Vivo Evaluation.

Past studies have shown that the hot spring effect can promote wound healing. Mild thermal stimulation and metal ions can promote angiogenesis. In this study, the hot spring effect was simulated by thermosensitive PNIPAAm hydrogel loaded with copper sulfide nanoparticles. Heat stimulation could be generated through near-infrared irradiation, and copper ions solution could be pulsed. On the other hand, the CS/PVA nanofiber membrane was attached to the bottom of the hydrogel to simulate the extracellular matrix structure, thus improving the wound healing ability. The CS/PVA nanofiber membrane was prepared by electrospinning, and the appropriate prescription and process parameters were determined. The nanofiber membrane has uniform pore size, good water absorption and permeability. The poor mechanical properties of PNIPAAm hydrogel were improved by adding inorganic clay. The temperature of the hydrogel loaded with CuS nanoparticles reached 40 °C under near-infrared light irradiation for 20 min, and the release rate of Cu2+ reached 26.89%. The wound-healing rate of the rats in the combined application group reached 79.17% at 13 days, demonstrating superior results over the other control groups. Histological analyses show improved inflammatory response at the healed wound area. These results indicate that this combined application approach represents a promising wound treatment strategy.

Five-FU@CuS/NH2 -UiO-66 as a drug delivery system for 5-fluorouracil to colorectal cancer cells.

In this study, copper sulfide nanoparticles (CuS-NPs), which can improve the antiproliferative properties of conventional anticancer drugs such as 5-fluorouracil (5-FU), were incorporated into the pores of amine-functionalized UiO-66 (CuS/NH2 -UiO-66). The introduced nano-drug delivery system was exerted to perform an in vitro treatment on CT-26 mouse colorectal cancer cells. The synthesized final product was labeled as 5-FU@CuS/NH2 -UiO-66 and characterized through conventional methods including X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis, Ultraviolet-Visible (UV-Vis) analysis, Inductively coupled plasma mass spectrometry (ICP-MS), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In contrast to 5-FU, the outcomes of the cytotoxicity assay lacked any comparable results for 5-FU@CuS/NH2 -UiO-66.

In vitro evaluation of copper sulfide nanoparticles decorated with folic acid/chitosan as a novel pH-sensitive nanocarrier for the efficient controlled targeted delivery of cytarabine as an anticancer drug.

Nanoparticles (NPs) have gained more attention as drug delivery systems. Folic acid (FA)-chitosan (CS) conjugates, because of their biodegradability, low toxicity, and better stability, offer a pharmaceutical drug delivery tool. The aim of this work was to fabricate CuS NPs modified by CS followed by grafting FA as a nanocarrier for the delivery of cytarabine (CYT) as an anticancer drug. In this work, CuS NPs modified by CS and FA were successfully synthesized. The structural properties of the nanocarrier were characterized by using scanning electron microscopy, Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, and Brunauer-Emmett-Teller. The adsorption mechanism of CYT by adsorption isotherms, kinetics, and thermodynamics was deliberated and modeled. The in vitro CYT release behavior for the nanocarrier was 99% and 61% at pH 5.6 and 7.4, respectively. The adsorption behavior of CYT by CuS NPs -CS-FA was well explored by pseudo-second-order kinetic and Langmuir isotherm models by the coefficient of determination (R2 > 0.99). Thermodynamic results showed that the uptake of CYT by CuS NPs-CS-FA was endothermic and spontaneous. The experimental results showed that CYT/CuS NPs -CS-FA can be proposed as an efficient nanocarrier for the targeted delivery of anticancer drugs.

Composition controllable alga-mediated green synthesis of covellite CuS nanostructure: An efficient photocatalyst for degradation of toxic dye

A facile, convenient and green method has been devised for the synthesis of a covellite phase copper sulfide nanoparticles (CuSNPs) using aqueous extract of a green alga, Chlorella ellipsoidea. The algal phytochemicals are conjectured to have served as both reducing and capping agent. The absorption features in the NIR region of the UV–visible-NIR spectrum confirmed the formation of covellite copper sulfide nanostructures. The FTIR spectrum of the as-synthesized CuSNPs indicated the involvement of functional groups of biomolecule as surface-ligands on the outer surface of the nanoparticle. The XRD reflections were indexed to hexagonal phase covellite CuS structure. The TEM study revealed a predominantly spherical morphology of particle size in the range of 9–23 nm with some agglomeration. The dark field microscope images also confirm the formation of CuS nanoparticles. EDX analysis of the synthesized nanoparticles confirms the presence of only ‘Cu’ and ‘S’ indicating formation of pure CuS nanoparticles. The as-synthesized nanoparticles exhibited excellent photocatalytic property for the degradation of a water soluble toxic methylene blue dye under scattered sunlight. The dye degradation (rate = 0.03692 min−1) was ascertained to be pseudo-first order with regression coefficient, R2 being 0.96884. The photocatalyst is readily recoverable and showed excellent stability even after four cycles.

Inhibition of Melanosis and Quality Changes on Indian White Prawn Treated with Lemon and Pomelo Peel Extracts Conjugated with Copper Sulfide Nanoparticles during Chilled Storage

ABSTRACT The study was aimed at the assessment of lemon peel extract (LPE) and pomelo peel extract (PPE) conjugated with copper sulfide nanoparticles (CuSNPs) influence on melanosis formation and improving the quality of chilled stored Indian white shrimp (Fenneropenaeus indicus) after 15 days. Biochemical indices, microbial count, and sensory analysis was performed at 3 day intervals. The trimethylamine, total volatile base nitrogen, free fatty acid, and peroxide value of control was 18.01 ± 0.79 mgN/100 g, 45.08 ± 1.1 mgN/100 g, 0.14 ± 0.01% of oleic acid, and 16.42 ± 0.612 milliequivalents/kg, whereas LPE+PPE+CuSNPs was 10.94 ± 1.04 mgN/100 g, 17.51 ± 1.1 mgN/100 g, 0.091 ± 0.01% of oleic acid, and 7.57 ± 0.38 milliequivalents/kg, respectively, at the 15th day of storage. The biochemical indices, microbial count, and sensory score of the treated sample was significantly lower (P < .05) than the untreated sample at day 15. This study aimed to determine the effectiveness of this biopreservation technique, which could provide a new alternative in preservation techniques, as well as impact shelf life and product safety.

Neutrophil-erythrocyte hybrid membrane-coated hollow copper sulfide nanoparticles for targeted and photothermal/ anti-inflammatory therapy of osteoarthritis

Osteoarthritis (OA), as a chronic degenerative joint disorder, has seriously affected the life quality of patients. Despite lots of drug treatment strategies that have been studied, the therapeutic effect is still unsatisfactory due to the lack of prolonged circulation life and targeted delivery ability. Recently, functional cell membranes modified nanoparticles have been explored to achieve high-efficiency drug delivery. Herein, neutrophil-erythrocyte hybrid membranes-coated dexamethasone sodium phosphate (Dexp)-loaded hollow copper sulfide nanoparticles (D-CuS@NR NPs) were fabricated for OA treatment. Generally, we achieved the synergistic treatment of mild-heating, prolonged circulation, and targeted delivery in this system. In particular, this biomimetic nanoparticle showed significant cytocompatibility and anti-inflammatory ability in vitro due to cell membrane coating and photothermal responsive drug release under NIR irradiation. Importantly, in vivo explorations revealed that D-CuS@NR NPs combined with photothermal treatment obtained an excellent therapy effect for preventing the OA process. Hence, this novel hybrid membranes-coated CuS NPs showed significant therapeutic efficacy by local warming and targeted drug delivery , which might become a promising drug delivery vehicle for improving the therapeutic effect of OA. • This nanoparticle possesses lots of advantages, including long circulation effect, excellent target ability, and well photothermal conversion efficiency. • Combined with NIR treatment, this drug loaded nanoparticle gained outstanding anti-inflammatory effect and ability to protect articular cartilage in vivo . • This drug loaded nanoparticle provides a promising platform for inflammation related diseases.

Oxygen-Independent Sulfate Radical for Stimuli-Responsive Tumor Nanotherapy.

Variant modalities are quested and merged into the tumor nanotherapy by leveraging the excitation from external or intratumoral incentives. However, the ubiquitous hypoxia and the insufficient content of hydrogen peroxide (H2O2) in tumor microenvironments inevitably hinder the effective production of reactive oxygen species (ROS). To radically extricate from the shackles, peroxymonosulfate (PMS: HSO5 −)‐loaded hollow mesoporous copper sulfide (CuS) nanoparticles (NPs) are prepared as the distinct ROS donors for sulfate radical (•SO4 −)‐mediated and stimuli‐responsive tumor nanotherapy in an oxygen‐independent manner. In this therapeutic modality, the second near‐infrared laser irradiation, together with the released copper ions as well as the heat produced by CuS after illumination, work together to activate PMS thus triply ensuring the copious production of •SO4 −. Different from conventional ROS, the emergence of •SO4 −, possessing a longer half‐life and more rapid reaction, is independent of the oxygen (O2) and H2O2 content within the tumor. In addition, this engineered nanosystem also exerts the function of photoacoustic imaging and skin restoration on the corresponding animal models. This study reveals the enormous potential of sulfate radical in oncotherapy and broadens pave for exploring the application of multifunctional and stimuli‐responsive nanosystems in biomedicine.

Preclinical safety and hepatotoxicity evaluation of biomineralized copper sulfide nanoagents

Albumin-biomineralized copper sulfide nanoparticles (Cu2−xS NPs) have attracted much attention as an emerging phototheranostic agent due to their advantages of facile preparation method and high biocompatibility. However, comprehensive preclinical safety evaluation is the only way to meet its further clinical translation. We herein evaluate detailedly the safety and hepatotoxicity of bovine serum albumin-biomineralized Cu2−xS (BSA@Cu2−xS) NPs with two different sizes in rats. Large-sized (LNPs, 17.8 nm) and small-sized (SNPs, 2.8 nm) BSA@Cu2−xS NPs with great near-infrared absorption and photothermal conversion efficiency are firstly obtained. Seven days after a single-dose intravenous administration, SNPs distributed throughout the body are cleared primarily through the feces, while a large amount of LNPs remained in the liver. A 14-day subacute toxicity study with a 28-day recovery period are conducted, showing long-term hepatotoxicity without recovery for LNPs but reversible toxicity for SNPs. Cellular uptake studies indicate that LNPs prefer to reside in Kupffer cells, leading to prolonged and delayed hepatotoxicity even after the cessation of NPs administration, while SNPs have much less Kupffer cell uptake. RNA-sequencing analysis for gene expression indicates that the inflammatory pathway, lipid metabolism pathway, drug metabolism-cytochrome P450 pathway, cholesterol/bile acid metabolism pathway, and copper ion transport/metabolism pathway are compromised in the liver by two sizes of BSA@Cu2−xS NPs, while only SNPs show a complete recovery of altered gene expression after NPs discontinuation. This study demonstrates that the translational feasibility of small-sized BSA@Cu2−xS NPs as excellent nanoagents with manageable hepatotoxicity.Graphical

Electrospun CuS nanoparticles/chitosan nanofiber composites for visible and near-infrared light-driven catalytic degradation of antibiotic pollutants

• Electrospun CuS nanoparticles/chitosan nanofiber composites (ENFCs) were developed. • The removal mechanism of tetracycline includes adsorption and catalytic degradation. • Visible and near-infrared light-driven photo-Fenton degradation of tetracycline. • The degradation intermediates and possible transformation pathways were evaluated. In the present study, copper sulfide nanoparticles (CuS NPs)/chitosan nanofiber composites with photo-Fenton catalytic and photothermal activities were developed to enhance the removal of recalcitrant biomedical pollutants such as tetracycline (TC). CuS NPs were encapsulated in CS nanofibers by an electrospinning technique (CS ENFs) to obtain CuS@CS ENF composite (CuS@CS ENFC) membranes with high porosity and large surface areas. An investigation of the mechanism of TC removal revealed the complementary performances between adsorption of TC by CS ENFs and the Fenton-like reaction of TC with CuS NPs during the degradation of TC. The ENFCs were cross-linked with genipin (GP) to improve the stability of CuS NPs in long-term storage and the availability of the ENFCs over a wide pH range. CuS@CS ENFCs generated electron-hole pairs and local hyperthermia under near infrared (NIR) laser irradiation, which caused the H 2 O 2 -involved catalytic reaction on ENFCs to take place at a faster rate than in the dark. Compared to pristine CuS NPs, ENFCs were more easily separated from the reaction mixture, and the adsorption sites on ENFCs could be regenerated by the photo-Fenton catalytic degradation of TC. The ENFCs also exhibited antibacterial activity. ENFCs are eco-friendly and easily recyclable, so they have the potential for chemical engineering, biomedical, and environmental applications.

Microscopic-Scale Examination of the Black and Orange–Yellow Colours of Architectural Glazes from Aššur, Khorsabad and Babylon in Ancient Mesopotamia

Three major corpora of architectural glazed bricks from Ancient Mesopotamia dating to the Neo-Assyrian (Aššur and Khorsabad sites) and the Neo-Babylonian (Babylon site) Periods have been submitted to an in-depth comparative study of the orange–yellow and black glazes. Distinct hues in the orange–yellow range were observed according to the archaeological site. They appear to have been well mastered by the glassmakers, consisting in the ex situ preparation of the antique lead antimonate pigment and its mixing with transparent soda-lime glass frit or with the glass-forming components. The intentional addition of hematite or of Cu2+ colouring ions in a controlled amount is suggested in two cases. SEM-EDX and Raman analysis of the lead antimonate pigments have pointed out different chemical substitutions in their pyrochlore structure, mainly Fe3+ in the Sb5+ site and Ca2+ in the Pb2+ site, the proportion of which being correlated to the pigment shade (from pale yellow to orange–red). Part of these substitutions arises from the chemical reaction of the pigment with the hematite and glass melt during firing. Regarding the black glazes, an unexpected colouring technique involving copper sulphide nanoparticles together with the chromophore Fe3+-S2− is highlighted for Khorsabad (8th century BC) and for Babylon (6th century BC). For Aššur blacks, the study reveals a change in their colouring technique between the 9th and 8th centuries BC, from a colouration with Mn oxides to an enigmatic one that could also have involved copper sulphide nanoparticles.

Biosynthesis and characterization of carbon quantum Dots@CuS composite using water hyacinth leaves and its usage in photocatalytic dilapidation of Brilliant Green dye

The investigation on the degradation of water-soluble dye Brilliant green was done by using CQDs@CuS. Water-dissolvable, green incandescent CQDs (carbon quantum dots) were fabricated with a high yield by carbonization of water hyacinth (Eichhornia crassipes) weed for the first time at a mild temperature without using any surface activating reagents or salt. The sol-gel method was utilized for the fabrication of copper sulfide (CuS) nanoparticles. An attempt was made to synthesize a composite of CuS NPs with CQDs. The structural and composition determination of synthesized CuS, CQD, and composite (CQDs/CuS) was done by HRTEM, FESEM, XRD, XPS, FTIR, BET, and EDS techniques. TEM and XRD studies are congruent with the amorphous and hexagonal structure of CQDs and CuS, respectively. Various quality parameters such as DO (dissolved oxygen), COD (chemical oxygen demand), conductivity, salinity, and TDS (total dissolved solids) have been measured to observe the extent of degradation of dye. The comparative study has proven that composite (CQDs/CuS) have shown the greatest photocatalytic action for the dilapidation of Brilliant green than CuS NPs only. The probable trail of the dilapidation of dye has also been suggested.