Efficient Phosphate Sequestration in Waters by the Unique Hierarchical 3D <i>Artemia</i> Egg Shell Supported Nano-Mg(OH)₂ Composite and Sequenced Potential Application in Slow Release Fertilizer

<i>Artemia</i> nauplii are important bait or food sources in aquaculture, but the egg shells after incubation are always subjected to discarding as natural wastes; therefore, application and utilization of the <i>Artemia</i> egg-shell wastes will be an important issue. Herein, we reported a new hybrid biomaterial by encapsulating nano-Mg­(OH)₂ onto discarded <i>Artemia</i> egg shells for phosphate sequestration enhancement. The unique hierarchically 3D-layered structure of <i>Artemia</i> egg shells can endow well-defined nano-Mg­(OH)₂ morphology and efficient phosphate adsorption performances. The results of the final hybrid biomaterial exhibit a wide pH dependent sorption process, strong affinity toward phosphate removal, and large sorption capacity. Moreover, the exhausted adsorbent shell–Mg-P can be further utilized as slow-release fertilizer without regular chemical regeneration. The efficient slow-release behaviors of phosphorus onto Shell–Mg–P for 30 days indicated the potential applicability as fertilizers. Additionally, the actual seedling tests further confirm that the shell–Mg–P can be readily used as a slow-release fertilizer for the soil improvement and crop productivity

Sorption Enhancement of Lead Ions from Water by Surface Charged Polystyrene-Supported Nano-Zirconium Oxide Composites

A novel hybrid nanomaterial was fabricated by encapsulating ZrO₂ nanoparticles into spherical polystyrene beads (MPS) covalently bound with charged sulfonate groups (−SO₃^–). The resultant adsorbent, Zr–MPS, exhibited more preferential sorption toward Pb­(II) than the simple equivalent mixture of MPS and ZrO₂. Such observation might be ascribed to the presence of sulfonate groups of the polymeric host, which could enhance nano-ZrO₂ dispersion and Pb­(II) diffusion kinetics. To further elucidate the role of surface functional groups, we encapsulated nano-ZrO₂ onto another two macroporous polystyrene with different surface groups (i.e., −N­(CH₃)₃⁺/–CH₂Cl, respectively) and a conventional activated carbon. The three obtained nanocomposites were denoted as Zr–MPN, Zr–MPC, and Zr–GAC. The presence of −SO₃^– and −N­(CH₃)₃⁺ was more favorable for nano-ZrO₂ dispersion than the neutral −CH₂Cl, resulting in the sequence of sorption capacities as Zr–MPS > Zr–MPN > Zr–GAC > Zr–MPC. Column Pb­(II) sorption by the four nanocomposites further demonstrated the excellent Pb­(II) retention by Zr–MPS. Comparatively, Zr–MPN of well-dispersed nano-ZrO₂ and high sorption capacities showed much faster breakthrough for Pb­(II) sequestration than Zr–MPS, because the electrostatic repulsion of surface quaternary ammonium group of MPN and Pb­(II) ion would result in a poor sorption kinetics. This study suggests that charged groups in the host resins improve the dispersion of embedded nanoparticles and enhance the reactivity and capacity for sorption of metal ions. Suitably charged functional groups in the hosts are crucial in the fabrication of efficient nanocomposites for the decontamination of water from toxic metals and other charged pollutants

TG curves of xerogels.

<p>(A) GO sheet and C16Py-GO gels in DMF, THF, and pyridine; (B) GO sheet and BPy-GO gels in DMF, cyclopentanone, and THF; (C) GO sheet and CTAB-GO gels in DMF, cyclopentanone, cyclohexanone, 1,4-dioxane, and THF.</p

Crystalline Dipeptide Nanobelts Based on Solid–Solid Phase Transformation Self-Assembly and Their Polarization Imaging of Cells

Controlled phase transformation involving biomolecular organization to generate dynamic biomimetic self-assembly systems and functional materials is currently an appealing topic of research on molecular materials. Herein, we achieve by ultrasonic irradiation the direct solid–solid transition of bioinspired dipeptide organization from triclinic structured aggregates to  nanofibers and eventually to monoclinic nanobelts with strong polarized luminescence. It is suggested that the locally high temperature and pressure produced by cavitation effects cleaves the hydrophobic, π–π stacking or self-locked intramolecular interactions involved in one phase state and then rearranges the molecular packing to form another well-ordered aromatic dipeptide crystalline structure. Such a sonication-modulated solid–solid phase transition evolution is governed by distinct molecular interactions at different stages of structural organization. The resulting crystalline nanobelts are for the first time applied for polarization imaging of cells, which can be advantageous to directly inspect the uptake and fate of nanoscale delivery platforms without labeling of fluorescent dyes. This finding provides a new perspective to comprehend the dynamic evolution of biomolecular self-organization with energy supply by an external field and open up a facile and versatile approach of using anisotropic nanostructures for polarization imaging of cells and even live organisms in future

Carrier-Free, Chemophotodynamic Dual Nanodrugs via Self-Assembly for Synergistic Antitumor Therapy

There are tremendous challenges from both tumor and its therapeutic formulations affecting the effective treatment of tumor, including tumor recurrence, and complex multistep preparations of formulation. To address these issues, herein a simple and green approach based on the self-assembly of therapeutic agents including a photosensitizer (chlorine e6, Ce6) and a chemotherapeutic agent (doxorubicin, DOX) was developed to prepare carrier-free nanoparticles (NPs) with the ability to inhibit tumor recurrence. The designed NPs were formed by self-assembly of Ce6 and DOX associated with electrostatic, π–π stacking and hydrophobic interactions. They have a relatively uniform size of average 70 nm, surface charge of −20 mV and high drug encapsulation efficiency, which benefits the favorable accumulation of drugs at the tumor region through a potential enhanced permeability and retention (EPR) effect as compared to their counterpart of free Ce6 solution. In addition, they could eradiate tumors without recurrence in a synergistic way following one treatment cycle. Furthermore, the NPs are safe without any activation of inflammation or immune response in separated organs. Taken together, the rationale of these pure nanodrugs via the self-assembly approach might open an alternative avenue and give inspiration to fabricate new carrier-free nanodrugs for tumor theranostics, especially for two small molecular antitumor drugs with the aim of combinational antitumor therapy in a synergistic way

Additional file 1: of Graphene Oxide-Polymer Composite Langmuir Films Constructed by Interfacial Thiol-Ene Photopolymerization

Supporting information. (DOCX 5395 kb

Efficient Removal and Recovery of Ag from Wastewater Using Charged Polystyrene-Polydopamine Nanocoatings and Their Sustainable Catalytic Application in 4‑Nitrophenol Reduction

This study addresses the long-standing challenges of removing and recovering trace silver (Ag) ions from wastewater while promoting their sustainable catalysis utilization. We innovatively developed a composite material by combining charged sulfonated polystyrene (PS) with a PDA coating. This composite serves a dual purpose: effectively removing and recovering trace Ag+ from wastewater and enabling reused Ag for sustainable applications, particularly in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The PS–PDA demonstrated exceptional selectivity to trace Ag+ recycling, which is equal to 14 times greater than the commercial ion exchanger. We emphasize the distinct roles of different charged functional groups in Ag+ removal and catalytic reduction performance. The negatively charged SO3H groups exhibited the remarkable ability to rapidly enrich trace Ag ions from wastewater, with a capacity 2–3 times higher than that of positively-N+(CH3)3Cl and netural-CH2Cl-modified composites; this resulted in an impressive 96% conversion of 4-NP to 4-AP within just 25 min. The fixed-bed application further confirmed the effective treatment capacity of approximately 4400 L of water per kilogram of adsorbent, while maintaining an extremely low effluent Ag+ concentration of less than 0.1 mg/L. XPS investigations provided valuable insights into the conversion of Ag+ ions into metallic Ag through the enticement of negatively charged SO3H groups and the in situ reduction facilitated by PDA. This breakthrough not only facilitates the efficient extraction of Ag from wastewater but also paves the way for its environmentally responsible utilization in catalytic reactions

Typical EDXS of xerogels originate from CTAB-GO gels in cyclopentanone.

<p>The Cu and Au peaks originate from the substrate of copper foil and the coated gold nanoparticles.</p

Highly Efficient Lead(II) Sequestration Using Size-Controllable Polydopamine Microspheres with Superior Application Capability and Rapid Capture

In this work, we successfully prepared the mussel-inspired polydopamine microspheres (PDA-Ms) with controllable sizes, through a facile self-oxidative polymerization method. The prepared PDA-M biomaterial with environmentally benign properties exhibits efficient lead­(II) sequestration against high salts of competitive Ca­(II), Mg­(II), or Na­(I) ions. It reveals 30 times greater than the commercial ion-exchanger 001x7 by selectivity evaluation. Kinetic results show that an exceedingly rapid lead­(II) uptake can be achieved below 1 min. More attractively, the prepared PDA-Ms further exhibit the distinguished application ability with superior treated capacity of ∼42000 kg contaminated water/kg sorbent, and the effluents can be reduced from 1000 μg/L to below 10 μg/L, reaching the drinking water standard (WHO), which is equal to 200 times greater than commercial ion exchanger resin (∼210 kg) and granular activated carbon (∼120 kg). In addition, the exhaust PDA-M material can be well regenerated and repeated use using binary 1% HCl + 5% Ca­(NO₃)₂ solution. X-ray photoelectron spectroscopy (XPS), zeta potential, and FT-IR analysis prove that such satisfactory performances can be ascribed to the following aspects (1) the well-dispersed nanoscale morphology and highly charged property will achieve the rapid adsorption and sufficient sorbent utilization. That is, the negatively-charged PDA sphere can exert the famous Donnan membrane effects for target lead­(II) enrichment and diffusion enhancement; (2) the strong amine and carbonyl/hydroxyl group within the matrix can offer sorption selectivity for powerful lead­(II) capture. Effective performances as well as environmentally friendly features suggest PDA-M material is a promising lead­(II)-removing candidate for water remediation

TGA data of GO sheet and amphiphiles-GO xerogels.

<p>TGA data of GO sheet and amphiphiles-GO xerogels.</p