Application of Optimization Response Surface for the Adsorption of Methylene Blue Dye onto Zinc-coated Activated Carbon.

The activated carbon was produced in the first phase of this investigation by chemically activating hazelnut shell waste with H3PO4. Composite materials were obtained by coating the activated carbon with zinc oxide, whose BET surface area was calculated as 1278 m2 g-1. ZnO-doped ZnO/AC composite was synthesized as an adsorbent for its possible application in the elimination of organic dyestuff MB, and its removal efficiency was investigated. Morphological properties of ZnO/AC were characterized using analytical methods such as XRD, SEM, and BET. The adsorption system and its parameters were investigated and modeled using the response surface method of batch adsorption experiments. The experimental design consisted of three levels of pH (3, 6.5, and 10), initial MB concentration (50, 100, and 150 mg L-1), dosage (0.1, 0.3, and 0.5 g 100 mL-1), and contact time (5, 50, and 95 min). The results from the RSM suggested that the MB removal efficiency was 98.7% under the optimum conditions of the experimental factors. The R2 value, which expresses the significance of the model, was determined as 99.05%. Adsorption studies showed that the equilibrium data fit well with the Langmuir isotherm model compared to Freundlich. The maximum adsorption capacity was calculated as 270.70 mg g-1.

Zinc and pH modulate the ability of insulin to inhibit aggregation of islet amyloid polypeptide.

Aggregation of the human islet amyloid polypeptide (hIAPP) contributes to the development and progression of Type 2 Diabetes (T2D). hIAPP aggregates within a few hours at few micromolar concentration in vitro but exists at millimolar concentrations in vivo. Natively occurring inhibitors of hIAPP aggregation might therefore provide a model for drug design against amyloid formation associated with T2D. Here, we describe the combined ability of low pH, zinc, and insulin to inhibit hIAPP fibrillation. Insulin dose-dependently slows hIAPP aggregation near neutral pH but had less effect on the aggregation kinetics at acidic pH. We determine that insulin alters hIAPP aggregation in two manners. First, insulin diverts the aggregation pathway to large nonfibrillar aggregates with ThT-positive molecular structure, rather than to amyloid fibrils. Second, soluble insulin suppresses hIAPP dimer formation, which is an important early aggregation event. Further, we observe that zinc significantly modulates the inhibition of hIAPP aggregation by insulin. We hypothesize that this effect arose from controlling the oligomeric state of insulin and show that hIAPP interacts more strongly with monomeric than oligomeric insulin.

Experimental and computational study on morin and its complexes with Mg2+, Mn2+, Zn2+, and Al3+: Coordination and antioxidant properties.

Morin (MRN), an intriguing bioflavonol, has received increasing interest for its antioxidant properties, as have its metal complexes (Mz+-MRN). Understanding their antioxidant behavior is critical to assess their pharmaceutical, nutraceutical potential, and therapeutic impact in the design of advanced antioxidant drugs. To this end, knowing the speciation of different H+-MRN and Mz+-MRN is pivotal to understand and compare their antioxidant ability. In this work, the protonation constant values of MRN under physiological ionic strength and temperature conditions (I = 0.15 mol L-1 and t = 37 °C), determined by UV-vis spectrophotometric titrations, are introduced. Thus, a reliable speciation model on H+-MRN species in aqueous solution is presented, which exhibits five stable forms depending on pH, supplemented by quantum-mechanical calculations useful to determine the proton affinities of each functional group and corresponding deprotonation order. Furthermore, potentiometry and UV-vis spectrophotometry have been exploited to determine the thermodynamic interaction parameters of MRN with different metal cations (Mg2+, Mn2+, Zn2+, Al3+). The antioxidant ability of H+-MRN and Mz+-MRN has been evaluated by the 2,2'-diphenyl-1-benzopyran-4-one (DPPH) method, and the Zn2+-MRN system has proven to afford the most potent antioxidant effect. Ab initio molecular dynamics simulations of Mz+-MRN species at all possible chelation sites and under explicit water solvation allowed for the fine characterization not only of the metal chelation modalities of MRN in explicit water, but also of the role played by the local water environment around the metal cations. Those microscopic patterns reveal to be informative on the different antioxidant capabilities recorded experimentally.

Multi-role conductive hydrogels for flexible transducers regulated by MOFs for monitoring human activities and electronic skin functions.

Metal organic frameworks (MOFs) have garnered significant attention in the development of stretchable and wearable conductive hydrogels for flexible transducers. However, MOFs used in hydrogel networks have been hampered by low mechanical performance and poor dispersibility in aqueous solutions, which affect the performance of hydrogels, including low toughness, limited self-recovery, short working ranges, low conductivity, and prolonged response-recovery times. To address these shortcomings, a novel approach was adopted in which micelle co-polymerization was used for the ex situ synthesis of Zn-MOF-based hydrogels with exceptional stretchability, robust toughness, anti-fatigue properties, and commendable conductivity. This breakthrough involved the ex situ integration of Zn-MOFs into hydrophobically cross-linked polymer chains. Here the micelles of EHDDAB had two functions, first they uniformly dispersed the Zn-MOFs and secondly they dynamically cross-linked the polymer chains, profoundly influencing the mechanical characteristics of the hydrogels. The non-covalent synergistic interactions introduced by Zn-MOFs endowed the hydrogels with the capacity for high stretchability, high stress, rapid self-recovery, anti-fatigue properties, and conductivity, all achieved without external stimuli. Furthermore, hydrogels based on Zn-MOFs can serve as durable and highly sensitive flexible transducers, adept at detecting diverse mechanical deformations with swift response-recovery times and high gauge factor values. Consequently, these hydrogels can be tailored to function as wearable strain sensors capable of sensing significant human joint movements, such as wrist bending, and motions involving the wrist, fingers, and elbows. Similarly, they excel at monitoring subtle human motions, such as speech pronunciation, distinguishing between different words, as well as detecting swallowing and larynx vibrations during various activities. Beyond these applications, the hydrogels exhibit proficiency in distinguishing and reproducing various written words with reliability. The Zn-MOF-based hydrogels hold promising potential for development in electronic skin, medical monitoring, soft robotics, and flexible touch panels.

Cu,Zn,I-Doped Carbon Dots with Boosted Triple Antioxidant Nanozyme Activity for Treatment of DSS-Induced Colitis.

Nanozyme-mediated antioxidative therapy is a promising star for treating a myriad of important diseases through eliminating excessive reactive oxygen species (ROS) such as O2·- and H2O2, a critical mechanism for inflammatory bowel disease (IBD). This work provides a high biocompatibility iodine-copper-zinc covalent doped carbon dots (Cu,Zn,I-CDs) with the catalase (CAT)-, superoxide dismutase (SOD)- and glutathione peroxidase (GPx)-like catalytic activities for treating ulcerative colitis (UC) by scavenging overproduced ROS. We found that I dopant aids in counteracting the positive charge at Cu,Zn dopants brought on by low pH, enabling Cu,Zn,I-CDs to process strong triple antioxidant nanozyme activities rather than Cu,Zn-CDs. Vitro experiments displayed that the Cu,Zn,I-CDs could scavenge the excessive ROS to protect cellular against oxidative stress and reduce the expression of proinflammatory cytokines, such as TNF-α, IL-1ß, and IL-6. In sodium dextran sulfate (DSS)-induced colitis mice models, Cu,Zn,I-CDs with excellent biocompatibility could effectively relieve the inflammation of the colon, containing the reduction of the colon length, the damaged epithelium, the infiltration of inflammatory cells, and upregulation of antioxidant genes. Therefore, the therapy of Cu,Zn,I-CD antioxidant nanozymes is an effective approach and provides a novel strategy for UC treatment.

Bioactive Metal Ion-Coordinated Dynamic Hydrogel with Antibacterial, Immunomodulatory, and Angiogenic Activities for Infected Wound Repair.

The repair of infected wounds is a complex physiopathologic process. Current studies on infected wound treatment have predominantly focused on infection treatment, while the factors related to delayed healing caused by vascular damage and immune imbalance are commonly overlooked. In this study, an extracellular matrix (ECM)-like dynamic and multifunctional hyaluronic acid (HA) hydrogel with antimicrobial, immunomodulatory, and angiogenic capabilities was designed as wound dressing for the treatment of infected skin wounds. The dynamic network in the hydrogel dressing was based on reversible metal-ligand coordination formed between sulfhydryl groups and bioactive metal ions. In our design, antibacterial silver and immunomodulatory zinc ions were employed to coordinate with sulfhydrylated HA and a vasculogenic peptide. In addition to the desired bioactivities for infected wounds, the hydrogel could also exhibit self-healing and injectable abilities. Animal experiments with infected skin wound models indicated that the hydrogel dressings enabled minimally invasive injection and seamless skin wound covering and then facilitated wound healing by efficient bacterial killing, continuous inflammation inhibition, and improved blood vessel formation. In conclusion, the metal ion-coordinated hydrogels with wound-infection-desired bioactivities and ECM-like dynamic structures represent a class of tissue bionic wound dressings for the treatment of infected and chronic inflammation wounds.

Tailoring the Ni-O Microenvironment in Amorphous-Dominated Highly Active and Stable Zn/NiO for Hydrogen Sulfide Detection.

Amorphous metal oxide semiconductor (MOS) materials are endowed with great promise to modulate electronic structures for gas-sensing performance improvement. However, the elevated-temperature requirement of gas sensors severely impedes the application of amorphous materials due to their low thermal stability. Here, a cationic-assisted strategy to tailor the Ni-O microenvironment in an amorphous-dominated Zn/NiO heterogeneous structure with high thermal stability was developed. It was found that 6 mol % Zn incorporation into amorphous NiO can effectively preserve the amorphous-dominated NiO phase even at high temperature. After calcination, the amorphous oxide can only be converted to crystals partly thus leading to the formation of amorphous/crystalline compounds, and the content of the amorphous phase can be adjusted by changing the calcination temperature. This amorphous/crystalline configuration can induce more electron transfer from Ni to Zn species, leading to the formation of active Niδ+ (δ>2) centers. Ex situ XPS and in situ Raman spectroscopy studies proved that the generated Niδ+ species pronouncedly promote the electron transfer during the H2S adsorption process. The amorphous/crystalline-6 mol % Zn/NiO sensor exhibits exceptional hydrogen sulfide response (2 ppm, 3.23), outstanding repeatability (as long as 5 weeks), and low limit of detection (as low as 50 ppb), surpassing most reported nickel-based gas sensors such as the crystal nickel oxide prepared in this work. The response and detection limit of the latter is only (2 ppm, 1.89) and (0.05 ppm) respectively. Our work thus opens up more opportunities for fundamental understanding and modulating of highly active amorphous sensing materials.

Insights into the Chemistry, Structure, and Biological Activity of Human Salivary MUC7 Fragments and Their Cu(II) and Zn(II) Complexes.

Mucin 7 (MUC7) is one of the salivary proteins whose role in the innate immune system is widely known, but still, neither its mechanism of action nor the impact of its metal coordination is fully understood. MUC7 and its fragments demonstrate potent antimicrobial activity, serving as a natural defense mechanism for organisms against pathogens. This study delves into the bioinorganic chemistry of MUC7 fragments (L1─EGRERDHELRHRRHHHQSPK; L2─EGRERDHELRHRR; L3─HHHQSPK) and their complexes with Cu(II) and Zn(II) ions. The antimicrobial characteristics of the investigated peptides and their complexes were systematically assessed against bacterial and fungal strains at pH 5.40 and pH 7.40. Our findings highlight the efficacy of these systems against Streptococcus sanguinis, a common oral cavity pathogen. Most interestingly, Zn(II) coordination increased (or triggered) the MUC7 antimicrobial activity, which underscores the pivotal role of metal ion coordination in governing the antimicrobial activity of human salivary MUC7 fragments against S. sanguinis.

Self-Powered Engineering of Cell Membrane Receptors to On-Demand Regulate Cellular Behaviors.

On-demand engineering of cell membrane receptors to nongenetically intervene in cellular behaviors is still a challenge. Herein, a membraneless enzyme biofuel cell-based self-powered biosensor (EBFC-SPB) was developed for autonomously and precisely releasing Zn2+ to initiate DNAzyme-based reprogramming of cell membrane receptors, which further mediates signal transduction to regulate cellular behaviors. The critical component of EBFC-SPB is a hydrogel film on a biocathode which is prepared using a Fe3+-cross-linked alginate hydrogel film loaded with Zn2+ ions. In the working mode in the presence of glucose/O2, the hydrogel is decomposed due to the reduction of Fe3+ to Fe2+, accompanied by rapid release of Zn2+ to specifically activate a Zn2+-responsive DNAzyme nanodevice on the cell surface, leading to the dimerization of homologous or nonhomologous receptors to promote or inhibit cell proliferation and migration. This EBFC-SPB platform provides a powerful "sensing-actuating-treating" tool for chemically regulating cellular behaviors, which holds great promise in precision biomedicine.

In vitroassessment of a gallium-doped glass polyalkenoate cement: chemotherapeutic potential, cytotoxicity and osteogenic effects.

Metastatic bone lesions are often osteolytic, which causes advanced-stage cancer sufferers to experience severe pain and an increased risk of developing a pathological fracture. Gallium (Ga) ion possesses antineoplastic and anti-bone resorption properties, suggesting the potential for its local administration to impede the growth of metastatic bone lesions. This study investigated the chemotherapeutic potential, cytotoxicity, and osteogenic effects of a Ga-doped glass polyalkenoate cement (GPC) (C-TA2) compared to its non-gallium (C-TA0) counterpart. Ion release profiles revealed a biphasic pattern characterized by an initial burst followed by a gradually declining release of ions. C-TA2 continued to release Ga steadily throughout the experimentation period (7 d) and exhibited prolonged zinc (Zn) release compared to C-TA0. Interestingly, the Zn release from both GPCs appeared to cause a chemotherapeutic effect against H1092 lung cancer cellsin vitro, with the prolonged Zn release from C-TA2 extending this effect. Unfortunately, both GPCs enhanced the viability of HCC2218 breast cancer cells, suggesting that the chemotherapeutic effects of Zn could be tied to cellular differences in preferred Zn concentrations. The utilization of SAOS-2 and MC3T3 cell lines as bone cell models yielded conflicting results, with the substantial decline in MC3T3 viability closely associated with silicon (Si) release, indicating cellular variations in Si toxicity. Despite this ambiguity, both GPCs exhibited harmful effects on the osteogenesis of primary rat osteoblasts, raising concerns about excessive burst Zn release. While Ga/Zn-doped GPCs hold promise for treating metastatic bone lesions caused by lung cancers, further optimization is required to mitigate cytotoxicity on healthy bone.

Titania (TiO2) nanotube surfaces doped with zinc and strontium for improved cell compatibility.

Titanium-based orthopedic implants are gaining popularity in recent years due to their excellent biocompatibility, superior corrosion resistance and lightweight properties. However, these implants often fail to perform effectively due to poor osseointegration. Nanosurface modification approaches may help to resolve this problem. In this work, TiO2 nanotube (NT) arrays were fabricated on commercially available pure titanium (Ti) surfaces by anodization and annealing. Then, zinc (Zn) and strontium (Sr), important for cell signaling, were doped on the NT surface by hydrothermal treatment. This very simple method of Zn and Sr doping takes less time and energy compared to other complicated techniques. Different surface characterization tools such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), static water contact angle, X-ray diffraction (XRD) and nanoindentation techniques were used to evaluate the modified surfaces. Then, adipose derived stem cells (ADSCs) were cultured with the surfaces to evaluate cell adhesion, proliferation, and growth on the surfaces. After that, the cells were differentiated towards osteogenic lineage to evaluate alkaline phosphatase (ALP) activity, osteocalcin expression, and calcium phosphate mineralization. Results indicate that NT surfaces doped with Zn and Sr had significantly enhanced ADSC adhesion, proliferation, growth, and osteogenic differentiation compared to an unmodified surface, thus confirming the enhanced performance of these surfaces.

Molecular modeling of multi-target analogs of huperzine A and applications in Alzheimer's disease.

CONTEXT: Given the diverse pathophysiological mechanisms underlying Alzheimer's disease, it is improbable that a single targeted drug will prove successful as a therapeutic strategy. Therefore, exploring various hypotheses in drug design is imperative. The sequestration of Fe(II) and Zn(II) cations stands out as a crucial mechanism based on the mitigation of reactive oxygen species. Moreover, inhibiting acetylcholinesterase represents a pivotal strategy to enhance acetylcholine levels in the synaptic cleft. This research aims to investigate the analogs of Huperzine A, documented in scientific literature, considering of these two hypotheses. Consequently, the speciation chemistry of these structures with Fe(II) and Zn(II) was scrutinized using quantum chemistry calculations, molecular docking simulations, and theoretical predictions of pharmacokinetics properties. From the pharmacokinetic properties, only two analogs, HupA-A1 and HupA-A2, exhibited a theoretical permeability across the blood-brain barrier; on the other hand, from a thermodynamic standpoint, the enantiomers of HupA-A2 showed negligible chelation values. The enantiomers with the most favorable interaction parameters were S'R'HupA-A1 (ΔGBIND = -40.0 kcal mol-1, fitness score = 35.5) and R'R'HupA-A1 (ΔGBIND = -35.5 kcal mol-1, fitness score = 22.61), being compared with HupA (ΔGBIND = -41.75 kcal mol-1, fitness score = 39.95). From this study, some prime candidates for promising drug were S'R'HupA-A1 and R'R'HupA-A1, primarily owing to their favorable thermodynamic chelating capability and potential anticholinesterase mechanism. METHODS: Quantum chemistry calculations were carried out at B3LYP/6-31G(d) level, considering the IEF-PCM(UFF) implicit solvent model for water. The coordination compounds were assessed using the Gibbs free energy variation and hard and soft acid theory. Molecular docking calculations were conducted using the GOLD program, based on the crystal structure of the acetylcholinesterase protein (PDB code = 4EY5), where the ChemScore function was employed with the active site defined as the region within a 15-Å radius around the centroid coordinates (X = -9.557583, Y = -43.910473, Z = 31.466687). Pharmacokinetic properties were predicted using SwissADME, focusing on Lipinski's rule of five.

CO2-Based Polycarbonates through Ring-Opening Polymerization of Cyclic Carbonates Promoted by a NHC-Based Zinc Complex.

A backbone-substituted N-heterocyclic carbene (NHC) zinc complex, in combination with alcohol initiators, has been shown to be an effective catalyst for the ring-opening polymerization (ROP) of trimethylene carbonate (TMC) to poly(trimethylene carbonate) (PTMC) devoid of oxetane linkages. The ROP of TMC proceeded in solution to give PTMC, possessing controlled molecular mass (2500 < Mn < 10000) and low dispersity (D ∼ 1.2). Changing the alcohol initiators, PTMCs with different end-groups were obtained, included a telechelic polymer. The results of MALDI-ToF and NMR analysis confirmed the controlled/living nature of the present ROP catalytic system, where side reactions, such as inter- and intramolecular transesterifications, were minimized during the polymerization. Solution studies in different solvents demonstrated the polymerization reaction to proceed via a mechanism first order in monomer and in catalyst. The zinc complex was also able to convert substituted cyclic carbonates, which were purposely synthesized from renewable feedstocks such as CO2 and 1,3-diols. For the asymmetric 2-Me TMC monomer, good regioselectivity was observed (Xreg up to 0.92). The excellent control of the polymerization process was finally brought to light through the preparation of polycarbonate/polyether triblock copolymers by using polyethylene glycol (PEG) as a macroinitiator and of well-defined di- and triblock polycarbonate/polylactide copolymers by sequential ROP of TMC and L-LA.

Stimulated Full-Thickness Cutaneous Wound Healing with Bioactive Dressings of Zinc and Cobalt Ion-Doped Bioactive Glass-Coated Eggshell Membranes in a Diabetic Rabbit Model.

Eggshell membrane-based biomedical applications have recently received great attention for their wound-healing properties. However, there are limited studies on diabetic wound healing. In this regard, we devised four types of composite eggshell membrane mats with nanoscale coatings of bioactive glass/Zn/Co-doped bioactive glass (ESM + BAG, ESM + ZnBAG, ESM + CoBAG, and ESM + ZnCoBAG) as wound-dressing materials for chronic nonhealing diabetic wounds. A detailed study of the physicochemical properties of the mats was conducted. In vitro studies demonstrated cytocompatibility and viability of human dermal fibroblasts on all four types of mats. The cells also attached finely on the mats with the help of cellular extensions, as evident from scanning electron microscopy (SEM) and rhodamine-phalloidin and Hoechst 33342 staining of cellular components. Endowed with bioactive properties, these mats influenced all aspects of full-thickness skin wound healing in diabetic animal model studies. All of the mats, especially the ESM + ZnCoBAG mat, showed the earliest wound closure, effective renewal, and restructuring of the extracellular matrix in terms of an accurate and timely accumulation of collagen, elastin, and reticulin fibers. Hydroxyproline and sulfated glycosaminoglycans were significantly (p < 0.01, p < 0.05) higher in ESM-ZnCoBAG-treated wounds in comparison to ESM-BAG-treated wounds, which suggests that these newly developed mats have potential as an affordable diabetic wound care solution in biomedical research.

Understanding competitive Cu2+ and Zn2+ adsorption onto functionalized cellulose fiber via experimental and theoretical approach.

Amidoxime groups were successfully introduced to develop a novel amidoxime-functionalized cellulose fiber (AO-Cell) for absorptive removal of heavy metal ions in wastewater. The chemical structure, and the competitive adsorption of Cu2+ and Zn2+ by AO-Cell were investigated by experiments study, Density functional theory (DFT) and molecular dynamic (MD) simulation. The results showed the N and O atoms in the amidoxime group can spontaneously interact with Cu2+ and Zn2+ through sharing long pair electrons to generate stable coordination structure, which was the dominant adsorption mechanism. Besides, the enlarged surface area, improved hydrophilicity and dispersion offered by AO-Cell facilitate the adsorption process by increasing the accessibility of absorption sites. As results of these synergetic modification, AO-Cell can remain effective in a wide pH range (1-6) and reach adsorption equilibrium within 60 min. At optimal conditions, the achieved theoretical adsorption capacity is as high as 84.81 mg/g for Cu2+ and 61.46 mg/g for Zn2+ in the solution with multiple ions. The competition between Cu2+ and Zn2+ in occupying the absorption sites arises from the difference in the metallic ion affinity and covalent index with the adsorbent as demonstrated by the MD analysis. Importantly, AO-Cell demonstrated favorable recyclability after up to 10 adsorption-desorption cycles.

Fabrication of N and S co-doped lignin-based porous carbon aerogels loaded with FeCo alloys and their application to oxygen evolution and reduction reactions in Zn-air batteries.

Zn-air batteries are a highly promising clean energy sustainable conversion technology, and the design of dual-function electrocatalysts with excellent activity and stability is crucial for their development. In this work, FeCo alloy loaded biomass-based N and S co-doped carbon aerogels (FeCo@NS-LCA) were fabricated from chitosan and lignosulfonate-metal chelates via liquid nitrogen pre-frozen synergistic high-temperature carbonization with application in electrocatalytic reactions. The abundant oxygen-containing functional groups on lignosulfonates have a chelating effect on metal ions, which can avoid the aggregation of metal nanoparticles during carbonation and catalysis, facilitating the construction of a nanoconfinement catalytic system with biomass carbon as the domain-limiting body and FeCo nanoparticles as the active sites. FeCo@NS-LCA exhibited catalytic activity (E1/2 = 0.87 V, JL = 5.7 mA cm-2) comparable to the commercial Pt/C in the oxygen reduction reaction (ORR), excellent resistance to methanol toxicity and stability. Meanwhile, the overpotential of oxygen evolution reaction (OER) was 324 mV, close to that of commercial RuO2 catalysts (351 mV). This study utilizes the coordination action of lignosulfonate to provide a novel and environmentally friendly method for the preparation of confined nano-catalysts and provides a new perspective for the high-value utilization of biomass resources.

Biopolymer electrolyte from banana powder-konjac glucomannan for zinc-ion batteries.

Herein, the novel eco-friendly biopolymer electrolytes consisting of banana powder and konjac glucomannan host matrix doped with zinc acetate salt were successfully fabricated through simple casting technique. The biopolymer electrolyte exhibited satisfactory thermal stability and mechanical properties; tensile strength (13.82 MPa); elongation at break (60.52 %) and Young's modulus (93.2 MPa). The electrochemical studies were carried out in symmetrical cells Zn/Zn cells. Biopolymer electrolyte showed favorable ionic conductivity of 5.59 × 10-4 S/cm along with stable cycling performance. The potential stability was found to be 2.52 V. The as-prepared biopolymer electrolytes demonstrated the potential as green, simple yet effective biopolymer electrolytes for zinc-ion batteries.

Composite Microgels Loaded with Doxorubicin-Conjugated Amine-Functionalized Zinc Ferrite Nanoparticles for Stimuli-Responsive Sustained Drug Release.

Purpose: The purpose of this study is to address the need for efficient drug delivery with high drug encapsulation efficiency and sustained drug release. We aim to create nanoparticle-loaded microgels for potential applications in treatment development. Methods: We adopted the process of ionic gelation to generate microgels from sodium alginate and carboxymethyl cellulose. These microgels were loaded with doxorubicin-conjugated amine-functionalized zinc ferrite nanoparticles (AZnFe-NPs). The systems were characterized using various techniques. Toxicity was evaluated in MCF-7 cells. In vitro release studies were conducted at different pH levels at 37 oC, with the drug release kinetics being analyzed using various models. Results: The drug encapsulation efficiency of the created carriers was as high as 70%. The nanoparticle-loaded microgels exhibited pH-responsive behavior and sustained drug release. Drug release from them was mediated via a non-Fickian type of diffusion. Conclusion: Given their high drug encapsulation efficiency, sustained drug release and pH-responsiveness, our nanoparticle-loaded microgels show promise as smart carriers for future treatment applications. Further development and research can significantly benefit the field of drug delivery and treatment development.

Probing the optical properties and toxicological profile of zinc tungstate nanorods.

Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons.

Rice powder template for hausmannite Mn3O4 nanoparticles and its application to aqueous zinc ion battery.

In this study, a simple calcination route was adopted to prepare hausmannite Mn3O4 nanoparticles using rice powder as soft bio-template. Prepared Mn3O4 was characterized by Fourier Transform Infra-Red Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray microanalysis (EDX), Powder X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) and Solid state UV-Vis spectroscopic techniques. Mn-O stretching in tetrahedral site was confirmed by FTIR and Raman spectra. % of Mn and O content supported Mn3O4 formation. The crystallinity and grain size was found to be 68.76% and 16.43 nm, respectively; tetragonal crystal system was also cleared by XRD. TEM clarified the planes of crystal formed which supported the XRD results and BET demonstrated mesoporous nature of prepared Mn3O4 having low pore volume. Low optical band gap of 3.24 eV of prepared Mn3O4 nanoparticles indicated semiconductor property and was used as cathode material to fabricate CR-2032 coin cell of Aqueous Rechargeable Zinc Ion Battery (ARZIB). A reversible cyclic voltammogram (CV) showed good zinc ion storage performance. Low cell resistance was confirmed by Electrochemical Impedance Spectroscopy (EIS). The coin cell delivered high specific discharge capacity of 240.75 mAhg-1 at 0.1 Ag-1 current density. The coulombic efficiency was found to be 99.98%. It also delivered excellent capacity retention 94.45% and 64.81% after 300 and 1000 charge-discharge cycles, respectively. This work offers a facile and cost effective approach for preparing cathode material of ARZIBs.