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Can nano-zero-valent iron, synthesized using oak leaf extract, be the key solution for water preservation, efficiently removing heavy metal ions and phosphate anions simultaneously? This research unveils how this technology not only promises high efficiency in the remediation of water resources, but also sets new standards for environmentally friendly processes. The high antioxidant capacity and high phenol content indicate suggest the possibility of oak-nZVI synthesis using oak leaf extract as a stable material with minimal agglomeration. The simultaneous removal of Cd and phosphates, as well as and Ni and phosphates was optimized by a statistically designed experiment with a definitive screening design approach. By defining the key factors with the most significant impact, a more efficient and faster method is achieved, improving the economic sustainability of the research by minimizing the number of experiments while maximizing precision. In terms of significance, four input parameters affecting process productivity were monitored: initial metal concentration (1–9 mg L−1), initial ion concentration (1–9 mg L−1), pH value (2–10), and oak-nZVI dosage (2–16 mL). The process optimization resulted in the highest simultaneous removal efficiency of 98.99 and 87.30% for cadmium and phosphate ions, respectively. The highest efficiency for the simultaneous removal of nickel and phosphate ions was 93.44 and 96.75%, respectively. The optimization process fits within the confidence intervals, which confirms the assumption that the selected regression model well describes the process. In the context of e of the challenges and problems of environmental protection, this work has shown considerable potential and successful application for the simultaneous removal of Cd(II) and Ni(II) in the presence of phosphates from water. [ABSTRACT FROM AUTHOR]

In this work, an upconversion luminescence (UCL) nanosensor for fast detection of ferric ion (Fe3+) and phosphate ion (Pi) is developed based on the inner-filter effect (IFE) between NaYF4:Yb/Er upconversion nanoparticles (UCNPs) and Fe3+-hypocrellin B (HB) complex. Fe3+-HB complex has strong absorption band (450–650 nm), which overlaps with the green emission peak of UCNPs at 545 nm. By adding Fe3+ and Pi, the UCNPs-HB system produces the red-shift change of absorption spectrum, which leads to the "on–off-on" process of IFE. So, with the specific recognition ability of HB for Fe3+ and the competitive complexation of Pi for Fe3+, the proposed nanosensor utilizes the UCL change to achieve the detection of the targets. For the detections of Fe3+, the linear range is 10–600 μM with a limit of detection (LOD) of 2.62 μM, and for Pi, the linear range is 5–100 μM with a LOD of 1.25 μM. The results for selectivity, precision, and recovery test are also satisfactory. Furthermore, the real sample detection shows that the proposed nanaosensor has a great potential in environmental and biological systems. An upconversion luminescence (UCL) nanosensor based on the inner-filter effect (IFE) between upconversion nanoparticles (UCNPs) and Fe3+-hypocrellin B (HB) complex for the detection of Fe3+ and phosphate ion has been proposed, which is promising to be a convenient and sensitive assay for monitoring Fe3+ and phosphate ion in different environments and biological systems. [ABSTRACT FROM AUTHOR]

A new type of adsorbent, Zr-doped three metal element adsorbent MgMnZr-LDH(3), was synthesized using Mg(NO3)2·6H2O, Mn(NO3)2·6H2O, and ZrCl2O·8H2O and employed to adsorb phosphate ions from an aqueous solution. The materials were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), an X-ray diffractometer (XRD), thermogravimetric–differential thermal analysis (TG−DTA), Fourier-transform infrared spectroscopy (FT-IR), and nitrogen adsorption/desorption experiments (N2 Brunauer–Emmett–Teller (BET)). The influences of the contact time (0~48 h), pH value (3, 5, 7, and 9), initial concentration (0~50 μg/dm3), and temperature (15, 25, 35, and 45 °C) on the adsorption of phosphate (P) ions were studied to investigate P adsorption from wastewater. The results showed that the Zr-modified three metal element adsorbent MgMnZr-LDH(3) had a superior adsorption effect on phosphate anions, which was about 2.18 times greater than that of the two metal element adsorbent MgMn-LDH(3). The MgMnZr-LDH(3) adsorption process conformed to the pseudo-second-order model. The adsorption isotherm can generally be described more satisfactorily for P using the Langmuir isotherm, and the maximum adsorption capacity of P was shown to be 30.8 mg/g. Under optimum experimental conditions (contact time: 24 h; pH 8; and temperature: 25 °C), the effect of competing anions (Cl−, SO42−, and NO3−) on the adsorption of phosphate ions was also investigated, and only the phosphate ions showed high selectivity. The good adsorption performance of MgMnZr-LDH(3) towards phosphate (P) ions was attributed to the anion exchange and complex reaction. [ABSTRACT FROM AUTHOR]

To improve the flame retardancy of bamboo scrimber, flame-retardant CaAl-PO4-LDHs were synthesized via the coprecipitation method using PO43− as the anion of an intercalated calcium–aluminum hydrotalcite in this work. The fine CaAl-PO4-LDHs were characterized via X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), cold field scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and thermogravimetry (TG). Different concentrations (1% and 2%) of CaAl-PO4-LDHs were used as flame retardants for the bamboo scrimber, and the flame retardancy of the bamboo scrimber was characterized via cone calorimetry. The results showed that CaAl-PO4-LDHs with excellent structures were successfully synthesized via the coprecipitation method in 6 h and at 120 °C. Compared with the bamboo scrimber without the flame retardant treatment, the peak heat release rate (HRR) of the bamboo scrimber treated with 1% and 2% concentrations of flame-retardant CaAl-PO4-LDHs decreased by 16.62% and 34.46%, the time taken to reach the exothermic peak was delayed by 103 s and 204 s and the Time to Ignition (TTI) was increased by 30% and 40%, respectively. Furthermore, the residual carbon of the bamboo scrimber did not change significantly, increasing by 0.8% and 2.08%, respectively. CO production decreased by 18.87% and 26.42%, respectively, and CO2 production decreased by 11.11% and 14.46%, respectively. The combined results show that the CaAl-PO4-LDHs synthesized in this work significantly improved the flame retardancy of bamboo scrimber. This work exhibited the great potential of the CaAl-PO4-LDHs, which were successfully synthesized via the coprecipitation method and applied as a flame retardant to improve the fire safety of bamboo scrimber. [ABSTRACT FROM AUTHOR]

The sensor SL can continuously recognized Al3+ and phosphates with good selectivity and fast response time, at the same time accompanied by a naked-eye identification specificity. Binding sites and recognition mechanism were discussed based on spectral characterization and DFT calculation. The sensor also had good recyclability and reusability. Besides, the practical applicability of sensor SL was evaluated by the experiments of zebrafish bioimaging and drug detection, and the results showed that the sensor SL has good practical application value. [Display omitted] • Sensor SL can detect Al3+ and phosphates continuously with high selectivity. • The sensor has the characteristic of twice continuous recognition and is more universal than single recognition sensor. • The target ion contents of three drugs were analyzed by SL and had a good effect. In this work, a fluorescence chemical sensor continuous detection Al3+ and phosphates by a Salamo-Salen-Salamo type compound (SL) was employed. The sensor continuously recognized Al3+ and phosphates with good selectivity and fast response time, and a low limit of detection of 0.25 μΜ and 0.96 μM, at the same time accompanied by a naked-eye identification specificity. The detection mechanism of SL towards Al3+ is due to the chelating fluorescence enhancement effect and ICT effect, and continuously towards phosphates is due to the collapse of the SL-Al3+ and coordination interaction between Al3+ and phosphates, by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, other spectral characterization and DFT calculation as evidence. In addition, the sensor had good recyclability and reusability. The distribution of Al3+ and phosphates in zebrafish cells was effectively monitored by confocal microscopy based on the good biocompatibility and tissue permeability of SL. Furthermore, the feasibility of using sensor SL to detect the content of Al3+ and phosphate ions in certain drugs was quantitatively analyzed through experiments. It was found SL had a good result in practical application. [ABSTRACT FROM AUTHOR]

AbstractIn the current study, Phosphate removal from aqueous solutions was studied using bimetallic Al/Cu modified natural zeolites (Z-Al/Cu). The Z-Al/Cu was synthesized in situ using simple chemical reduction and impregnation methods. The morphologies and structures of natural zeolites (NZ) and Z-Al/Cu were characterized by SEM, XRD, FTIR, and BET. Batch sorption experiments were carried out using various factors that can potentially influence the removal efficiency (initial pH, initial solution concentration, and adsorbent dosage). Experimental results showed higher adsorption of Z-Al/Cu as compared to NZ, indicating that the Al/Cu impregnation provides more adsorption sites to phosphate. The maximum adsorption of phosphate by the adsorbent was 99.32% at optimum pH 2, contact time of 60 min, and phosphate concentration of 25 mg/L. When the contact time between the adsorbent and adsorbate increased above the optimum time, the adsorption efficiency decreased due to the onset of the desorption process. Characterization results indicated that Al/Cu was successfully supported on the zeolites. Adsorption of phosphate by Z-Al/Cu adsorbent fitted well with Langmuir adsorption isotherm and pseudo-second-order kinetics within R2 = 0.913 and 0.999 respectively, which suggested that the adsorption process was a surface chemical reaction and mainly in a monolayer coverage manner. Reduction of removal efficiency, with regeneration cycles and in the presence of SO42-, was observed.

A magnetic zirconium hexacyanoferrate-based Prussian blue analog (MB@ZrHCF) nanozyme was synthesized using dopamine (DA) reduction-assisted method and employed for colorimetric PO43− sensing. The MB@ZrHCF exhibits enhanced peroxidase-mimicking activity and ultrafast catalytic rate via the color reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) oxidized by hydrogen peroxide (H2O2). The catalytic reaction mechanism of MB@ZrHCF catalyzing H2O2 to produce hydroxyl radical (∙OH) was studied. Then, MB@ZrHCF was successfully applied to the detection of H2O2. Additionally, the catalytic activity of the nanocomposite is inhibited due to the steric hindrance effect from the coordination of PO43− and Zr(IV) node. Based on this, the MB@ZrHCF nanozyme can be used to detect PO43− in two linear ranges (10–100 µM and 100–200 µM) with a limit of detection of 2.25 µM. The proposed colorimetric sensor possesses excellent selectivity and reliability for PO43− sensing, which can be successfully applied to detect PO43− in sea and tap water samples. [ABSTRACT FROM AUTHOR]

In the current study, Phosphate removal from aqueous solutions was studied using bimetallic Al/Cu modified natural zeolites (Z-Al/Cu). The Z-Al/Cu was synthesized in situ using simple chemical reduction and impregnation methods. The morphologies and structures of natural zeolites (NZ) and Z-Al/Cu were characterized by SEM, XRD, FTIR, and BET. Batch sorption experiments were carried out using various factors that can potentially influence the removal efficiency (initial pH, initial solution concentration, and adsorbent dosage). Experimental results showed higher adsorption of Z-Al/Cu as compared to NZ, indicating that the Al/Cu impregnation provides more adsorption sites to phosphate. The maximum adsorption of phos- phate by the adsorbent was 99.32% at optimum pH 2, contact time of 60 min, and phosphate concentration of 25 mg/L. When the contact time between the adsor- bent and adsorbate increased above the optimum time, the adsorption efficiency decreased due to the onset of the desorption process. Characterization results indicated that Al/Cu was successfully supported on the zeolites. Adsorption of phosphate by Z-Al/Cu adsorbent fitted well with Langmuir adsorption isotherm and pseudo-second-order kinetics within R² = 0.913 and 0.999 respectively, which sug- gested that the adsorption process was a surface chemical reaction and mainly in a monolayer coverage manner. Reduction of removal efficiency, with regeneration cycles and in the presence of SO42-, was observed. [ABSTRACT FROM AUTHOR]

A bis‐heteroleptic Ru(II) complex, 1[PF6]2, of substituted pyridyl‐1,2,3‐triazole ligand (L1) has been developed for the photoluminescence(PL) detection of phosphate (HP2O73−/PPi) and Ag+ ion in distilled CH3CN and mixed aqueous buffer (carbonate‐bicarbonate buffer/CH3CN; v/v, 9.5 : 0.5; 0.1 M; pH 10.6) at two different wavelengths, respectively. The multianalyte probe, 1[PF6]2 showed significant PL enhancement in the presence of H2PO4−, PPi, and Ag+ with low detection limits of 0.48 μM, 0.43 μM, and 0.46 μM, respectively. The PL enhancement with phosphate ions is due to the triazole C−H⋅⋅⋅anion H‐bonding interaction that has been supported by 1H NMR titration (for PPi) and single‐crystal X‐ray structure (for H2PO4−). A unique Ag(I)‐triazolide complex formation is responsible for the PL enhancement in Ag+ ion detection. Triplet state TDDFT calculations were carried out to explain the PL enhancement of 1 ⋅ PPi and 1‐Ag adducts. In 1‐Ag, the L1 ligand becomes a better σ‐donor as well as π‐donor. Consequently, the 3MLCT‐3MC energy gap is increased and the 1‐Ag emits efficiently from the 3MLCT state. The probe also shows low cytotoxicity against Hela cells and is used for intracellular Ag+ imaging. [ABSTRACT FROM AUTHOR]

Species and sex confirmation of the biological specimen play a crucial role in crime investigation. However, the specimen found in the scene is always trace quantity, which is hard to be analyzed by current methods. Moreover, the time-consuming DNA extraction, sophisticated apparatus, and complex data processing make it difficult to satisfy the demand of speediness and convenience for point-of-care tests. In this study, we first exhibit a phosphate-based visual system for field-based species and sex identification derived from trace bloodstain. By introducing phosphate ion-based colorimetry into loop-mediated isothermal amplification (LAMP) for result interpretation, not only the bloodstain can be directly submitted to mitochondrial variant amplification owing to the enhanced amplification efficiency by pyrophosphate ion hydrolyzation, but also the colorimetric signal can be recognized by the naked eye for result output within 30 min through molybdophosphate generation. Aerosol contamination, the major conflict of LAMP, has been solved once and for all by integrating uracil-DNA glycosylase into this system that still holds on a constant temperature. As a demonstration, cytochrome b and Y-chromosomal amelogenin are employed to identify species and sex respectively, which has achieved a highly sensitive and specific distinguishability under a strong interferential background. Accurate results can be obtained from both the simulative degraded and dated specimen, which indicates that this novel system may serve as a promising tool in forensic practice. [Display omitted] • The species and sex identification can be interpreted with naked eye within 30 min. • Enhanced amplification efficiency by PPi hydrolyzed facilitates crude sample analysis. • Trace bloodstain can be directly submitted to analysis avoiding DNA purification. • Aerosol contamination is eliminated thoroughly based on Uracil-DNA Glycosylase. [ABSTRACT FROM AUTHOR]

An anion exchanger ('Cell-AE') was prepared by grafting acrylonitrile (AN) onto carbon cloth waste followed by subsequent modification with hydrazine hydrate and dimethyl sulfate. The effect of radiation dose and monomer concentration was investigated. The nitrate ( NO 3 - ) and phosphate ( PO 4 3 - ) sorption potentials of the 'Cell-AE' was evaluated via batch mode. The 'Cell-AE' showed a higher adsorption affinity towards PO 4 3 - than NO 3 - . Similarly, the PO 4 3 - and NO 3 - adsorption was described by Dubinin–Radushkevich (D-R) and Redlich-Peterson (R-P) models, respectively. The present study conclusively proffered a potential mitigation approach to carbon cloth waste management. [ABSTRACT FROM AUTHOR]

Phosphorus (as phosphate ions) is an essential ingredient that is commonly used in agriculture as both a fertilizer as well as in industry as a detergent which causes significant water pollution. The nanomaterials are mainly involved in removing these ions due to their high surface area. In this study, magnesium oxide nanoparticles (MgO NPs) has been synthesized by microwave method. XRD, AFM and SEM were used to investigate the synthesized MgO nanoparticles. The average particles size of MgO NPs calculated to be range (25-39 nm), and has a cubic structure. The synthesized nanoparticles were tested to remove phosphate ions from aqueous solutions. From the resulted, which found that at a pH 12, temperature 298°C the highest adsorption efficiency of phosphate (72%) as a contact time was 150 minutes. It was found that the adsorption mechanism was spontaneous and endothermic by thermodynamic measurements. Generally, the data indicated a good effectiveness of MgO in the removal of phosphate. [ABSTRACT FROM AUTHOR]

Coordination polymers (CPs) with aggregation‐induced emission (AIE) have been widely applied to fluorescent sensing based on the strategy of electron or energy transfer. Novel strategies still need to be explored to promote the application of AIE CPs in fluorescent sensing. Herein, an infinite coordination polymer (ICP), synthesized from Zn2+, adenine and AIE ligand 4,4'‐diphenic acid (DPA), was used to detect phosphate ion (Pi) via aggregation state modulation. The ICP was decomposed in the presence of Pi due to the coordination of Pi with Zn2+, which disaggregated AIE ligand DPA along with fluorescence quenching. The ICP quantified Pi in the concentration range from 30 to 600 μM with a detection limit of 5 μM, which was much lower than the physiological level, and was applied to detecting Pi in urine with spiked recoveries in the range of 82.0–115.5 %. This work provides a novel strategy to design fluorescent probes with AIE CPs for the analytes exhibiting the decomposing ability, promoting the application of AIE CPs in fluorescent sensing. [ABSTRACT FROM AUTHOR]

Herein, granulation molding was conducted using a disc granulator via a two-step rolling granulation method. Red mud (RM), which has good absorption efficiency on phosphate ions in wastewater, was used as the raw material, and some amount of fly ash was doped as a pore-assisting modifier. High belite cement and hydroxypropyl methyl cellulose were used as binders; HCl was the active modifier, and H2O2 and MnO2 were the pore regulators. A non-thermally activated red mud particle adsorbent (ARMFA) was prepared via an optimal formulation of the above additives, and the adsorbent had 9.25 pH, 40.54 m2 g−1 specific surface area, 2.10 cm³ g−1 pore volume, 1.31 KPa compressive strength, and 3.72% pulverization rate at 24 h. This adsorbent can be used to adsorb phosphate ions (P) in phosphate ore dressing plant discharge wastewater. For 156.7 mg L–1 total initial P concentration, 25 g L–1 ARMFA amount, 14 h adsorption time, and 38.46 mg g–1 adsorption and 98.17% removal rate of the total P were achieved. Particularly, the toxicity of ARMFA was below the standard limit. When the pH was 8–9, P mainly existed in the form of HPO4 2− and PO4 3−. These ions reacted with Ca2+, Na+, Al3+, Mg2+, etc., and formed strong chemical bonds through surface deposition and ion exchange, which were then distributed on the inner surface of the ARMFA channels. The adsorption of P by the ARMFA is per the pseudo-second-order dynamics model, and the Langmuir model can best describe the adsorption process. Phosphorus, fluorine, and other toxicity indicators in the tailwater after adsorption reached the standard requirements. After adsorbing P, the alkalinity of the ARMFA decreased, and the metal ions and toxic substances were consolidated. These results provide a foundation for the use of RM in building materials. [ABSTRACT FROM AUTHOR]

The removal efficiency of phosphate ion from aqueous media using magnesium oxide/iron molybdate (MgO/Fe2(MoO4)3) nanocomposite was investigated. MgO nanoparticles were chemically modified by ferric molybdate. Then, the structure and morphology of the nanocomposite was completely investigated using different analyses such as SEM, EDX/Map, FTIR, XRD, TGA, BET, and TEM. The TEM analysis demonstrated that the particles in the mentioned nano-composite were on a nanoscale. BET analysis proved that the nanocomposite was mesoporous with mean pore size of 9.4 nm. The sorption outcomes demonstrated that the highest phosphate sorption yield was achieved at 98.38%, exhibiting remarkable sorption efficiency. Carbonate ions showed to have the highest interfering impact compared to sulfate and nitrate ions, since phosphate ion removal efficiency decreased significantly when carbonate and phosphate ions were simultaneously available in the solution. The thermodynamic studies demonstrated that the current sorption process was spontaneous, possible, and exothermic. The sorption equilibrium investigation showed that the Freundlich isotherm model can describe the adsorption of phosphate ion better than can the Langmuir model, and the maximum sorption capacity was obtained as 30.21 mg/g. Additionally, the adsorbent was successfully regenerated four times and was able to perform the sorption and desorption process well. [ABSTRACT FROM AUTHOR]

Nonmammalian collagens have attracted significant attention owing to their potential for use as a source of cell scaffolds for tissue engineering. Since the morphology of collagen fibrils controls cell proliferation and differentiation, its regulation is essential for fabricating scaffolds with desirable characteristics. In this study, we evaluated the effects of the phosphate ion (Pi) concentration on the characteristics of fibrils formed from swim bladder type I collagen (SBC) and skin type I collagen (SC) from the Bester sturgeon. An increase in the Pi concentration decreased the fibril formation rate, promoted the formation of thick fibrils, and increased the thermal stability of the fibrils for both SBC and SC. However, the SBC and SC fibrils exhibited different fibril formation rates, degrees of fibrillogenesis, morphologies, and denaturation temperatures for the same reaction conditions. Finally, by regulating the Pi concentration, various types of SBC and SC fibrils could be coated on cell culture wells, and fibroblasts could be cultured on them. The results showed that thin fibrils enhance fibroblast extension and proliferation, whereas thick fibrils restrain fibroblast extension but orient them in the same direction. The results of this study suggest that SBC fibrils, which exhibit diverse morphologies, are suitable for use as a novel scaffold material, whose characteristics can be tailored readily by varying the Pi concentration. • We evaluated the effects of Pi on in-vitro fibrillogenesis of sturgeon type I collagen. • Higher Pi concentrations limit the rate and degree of fibrillogenesis. • Thicker fibrils are formed at higher Pi concentrations. • Thin fibrils aid fibroblast extension while thick fibrils align them. • Both types of fibrils retard fibroblast proliferation. [ABSTRACT FROM AUTHOR]

Response mechanism of the electrode is elucidated in terms of (hydrogen) phosphate accelerating oxidation of CoII to CoIII for the first time. Cyclic voltammetric techniques in conjunction with XRD, XPS and Raman characterizations have demonstrated unambiguously the response of cobalt (II) hydroxide electrode involves a phosphate and hydrogen ion dependent charge transfer process. Phosphate ions induce Co(OH) 2 transformed into CoOOH within interlayer adsorption and restored the initial state after reduction. Meanwhile, the in common structural between Co(OH) 2 and CoOOH prevents extensive structural convertibility upon cycling, result in the advantage of reversibility in phase transformation. Demonstrated sustainable technique offered the determination of phosphate with robust reproducibility (1000 cycles), long storage stability (6 months) and selectivity (potential interference: Cl−, NO 3 −, SO 4 2− and HCO 3 −), achieving a detection limit of 5 × 10−8 M over a wide linear range up to 1.28 mM. Presented work provided insights into the unique selectivity towards phosphate in cobalt based sensors, which may inspire the rational design of Co(OH) 2 -based electrodes with superior electrochemical performance or extended applications. [Display omitted] • Response mechanism of the electrode is elucidated in terms of phosphate accelerates oxidation of CoII to CoIII for the first time. • Phosphate ions are capable of inducing Co(OH) 2 transforms into CoOOH within interlayer adsorption, and restored the initial state after reduction. • Demonstrated an innovative and feasible method for detecting phosphate concentrations with lower detection limit, robust reproducibility, and anti-interference by Co(OH) 2 electrode. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to use phosphate ions in aqueous solution for production of phosphated organic fertilizers by using pine needles. Pine needles (PN), pine needles modified by NaOH (Na-MPN), pine needles modified by CH3OH-NaOH solutions (MeOH-MPN) were used as adsorbents. Adsorbent amount (0.1-0.3 g/100 mL), contact time (15-1,440 min), pH (3-10), initial concentration (20-150 ppm) and temperature (25°C, 35°C, and 50°C) were the selected parameters. Microstructures, chemical and physical properties of the adsorbents were characterized, respectively, by Fourier transform infrared spectroscopy (PerkinElmer Spectrum 100, USA) and scanning electron microscope (ZEISS Supra 40VP, USA). According to experimental results and analyses, it was shown that lignin compound found in pine needles decreases the phosphate adsorption capacity of pine needles. The pseudo-second-order model for the Na-MPN adsorbent optimally fits the phosphate adsorption kinetics, and the data are coherent with Langmuir and Dubinin-Radushkevich (D-R) adsorption isotherm models. Furthermore, thermodynamic studies show that the adsorption process occurs spontaneously and naturally in an exothermic manner. As a result, it has been determined that it can be used as phosphated organic fertilizer in soils and waters where phosphate is insufficient by adsorbing phosphate ions to pine needles whose lignin were removed from waters having high phosphate concentration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ionic charge carriers and their transport in phosphoric acid-water mixtures from NMR. • Maximum concentration of H 3 O + and H 2 P O 4 - at mole fractions around 0.8. • Maximum in electrical conductivity and ionic mobility at mole fractions around 0.8. • Water dependence of the viscoelastic and kinematic properties elucidated. • Phosphoric acid dissociation in the DMEM media was studied to understand phosphate ionic kinetics inside the body fluid. The study investigates the formation and transportation of ionic charge carriers in phosphoric acid-water system. This investigation encompasses an analysis of 1H and 31P NMR chemical shifts, self-diffusion coefficients, spin-lattice relaxation rates, spin-spin relaxation rates, activation energies, dissociation constants, electrical conductivity, and Raman shifts, along with FTIR spectra across various water concentrations. Significantly, the maxima observed in these curves at around 0.8 water molar fraction predominantly from the unique molecular arrangement between phosphoric acid and water molecules, influenced by a hydrogen bonding network. These findings yield valuable insights into phosphate ion kinetics within body fluids, covering essential aspects like hydrogen bonding networks, ionization processes, and the energy kinetics of phosphoric dissociation. A customized semiempirical model is applied to calculate dissociated species (water, phosphoric acid, and hydronium ion) at different water contents within a wide range of water mole fraction. Furthermore, this investigation extends to the dissociation of phosphoric acid in DMEM cell culture media, offering a more precise model for phosphate ionic kinetics within body fluids, especially at nominal phosphate concentrations of approximately 1 : 700 μ L. [ABSTRACT FROM AUTHOR]

Abstract The effect of hydroxyapatite on structure, particle size, and band gap energy of silver orthophosphate (Ag 3 PO 4) have been investigated. The hydroxyapatite as a source of phosphate ion was prepared using the coprecipitation of CaCl 2 and KH 2 PO 4. To produce the product of Ag 3 PO 4 , the as-synthesized hydroxyapatite was suspended in water and quickly added to a silver nitrate solution. The obtained photocatalysts were characterized using XRD, SEM, DRS, and XPS. The high crystallinity of single phase Ag 3 PO 4 was easily produced using the hydroxyapatite. Photocatalytic activities of the product were evaluated using RhB decomposition under blue light irradiation. The hydroxyapatite as a source of phosphate ion dramatically decreases the particle size and increases the absorption in the visible region. This obtained photocatalyst significantly improves the photocatalytic activity. The mechanism of reaction works in the following order: holes > superoxide radical > hydroxyl radical. Graphical abstract Image Highlights • The Ag 3 PO 4 was successfully synthesized using hydroxyapatite. • Hydroxyapatite could be used as a source of phosphate ion. • Hydroxyapatite dramatically decreases the particle size of Ag 3 PO 4. • The highly enhanced Ag 3 PO 4 could be easily produced. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Hepatic claudin-3 (Cldn3) expression decreases with aging in mice. • Cldn3 deficiency causes dysfunction in the paracellular barrier for phosphate ions. • Dysfunctional biliary metabolism of phosphate ions induces calcium phosphate core formation. • A calcium phosphate core induces cholesterol gallstone formation. Abstract Background & Aims Most cholesterol gallstones have a core consisting of inorganic and/or organic calcium salts, although the mechanisms of core formation are poorly understood. We examined whether the paracellular permeability of ions at hepatic tight junctions is involved in the core formation of cholesterol gallstones, with particular interest in the role of phosphate ion, a common food additive and preservative. Methods We focused on claudin-3 (Cldn3), a paracellular barrier-forming tight junction protein whose expression in mouse liver decreases with age. Since Cldn3- knockout mice exhibited gallstone diseases, we used them to assess the causal relationship between paracellular phosphate ion permeability and the core formation of cholesterol gallstones. Results In the liver of Cldn3- knockout mice, the paracellular phosphate ion permeability through hepatic tight junctions was significantly increased, resulting in calcium phosphate core formation. Cholesterol overdose caused cholesterol gallstone disease in these mice. Conclusion We revealed that in the hepatobiliary system, Cldn3 functions as a paracellular barrier for phosphate ions, to help maintain biliary ion homeostasis. We provide in vivo evidence that elevated phosphate ion concentrations play a major role in the lifestyle- and age-related risks of developing cholesterol gallstone disease under cholesterol overdose. Lay summary Herein, we reveal a new mechanism for cholesterol gallstone formation, in which increased paracellular phosphate ion permeability across hepatobiliary epithelia causes calcium phosphate core formation and cholesterol gallstones. Thus, altered phosphate ion metabolism under cholesterol overdose plays a major role in the lifestyle- and age-related risks of developing cholesterol gallstone disease. [ABSTRACT FROM AUTHOR]

We report for the first time a study on ionophore‐graphene based polymeric membranes to develop better sensing performance in sensitivity and selectivity. This sensing is based on ion‐transfer stripping voltammetry (ITSV) at interface between two immiscible electrolyte solutions (ITIES) technique which will lead to an electrochemical phenomenon to create highly sensitive sensors. We have integrated nanotechnology through electrochemistry and sensor techniques as part of an important environmental monitoring strategy to evaluate lead and dihydrogen phosphate ion. [ABSTRACT FROM AUTHOR]

We prepared a variety of nickel-aluminum complex hydroxides, investigated their physicochemical properties, and evaluated their ability to adsorb phosphate ions (the molar ratios of nickel to aluminum, 1:2, 1:1, 2:1, 3:1, and 4:1, are referred to as NA12, NA11, NA21, NA31, and NA41). NA12 and NA11 have amorphous structures; their specific surface areas and the concentration of associated hydroxyl groups were greater than those of other adsorbents. The number of phosphate ions adsorbed onto NA12 and NA11 was greater than that onto other adsorbents. These results indicated that the phosphate ion adsorption is related to the specific surface area and the amount of hydroxyl groups. The adsorption isotherm data, and the effects of contact time and pH on the adsorption were investigated; our results implied that both the Freundlich equation model and the pseudo-second-order kinetic model describe the adsorption of phosphate ions by NA11. We showed that phosphate ions adsorbed onto NA11 can be desorbed by sodium hydroxide solution at different concentrations and that NA11 could be reused for at least three repeated cycles of phosphate ion adsorption and desorption. This study illustrates that NA11 has the potential for practical application as an adsorbent for phosphate ions from wastewater. [ABSTRACT FROM AUTHOR]

Essential biomolecules of the human body and plant growth depend upon the proper amount of phosphate ions. Phosphorus has critical values in both agricultural and biomedical applications. There is a need for inexpensive, portable, repeatable, highly sensitive, and field deployable sensors with wide detection range to monitor the health of water system and field soil. This paper aims to develop an electrochemical phosphate sensor using novel ammonium molybdate tetrahydrate/silver nanowires (AMT/AgNWs) modified screen printed electrode (SPE) for phosphate detection to achieve simplicity, high sensitivity, wide detection range, and high repeatability and portability. The cyclic voltammetry measurements exhibited the sensitivities of AMT modified SPE without and with AgNWs are 0.1~\mu \textA/\mu \textM and 0.71~\mu \textA/\mu \textM , respectively. The use of highly conductive AgNWs significantly increased the sensitivities of the AMT/SPE. Besides, AgNWs and AMT modified SPE (AMT/AgNWs/SPE) showed a very wide detection range of 5~\mu \textM –1 mM. The maximum relative standard deviation of around 5% confirms the repeatability of the proposed sensor. This paper suggests that AMT/AgNWs/SPE is promising for simple, low-cost, and portable phosphate ion detection. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Polycaprolactone (PCL)-biphasic calcium phosphate (BCP) scaffolds fabricated using Melt-Stretching and Compression Molding (MSCM) can release calcium and phosphate ions, which are essential for bone formation. OBJECTIVE: Responses of the osteoblasts seeded on three groups of scaffolds including group A; PCL-20% BCP (%wt), group B; PCL-30% BCP and group C (control); pure PCL (100% PCL) were evaluated. METHODS: The cell-scaffold constructs were made by seeding osteoblast cell lines at 1 × 105 cells/scaffold. The constructs of each group were divided for culturing in proliferation medium (PR) and osteogenic induction medium (OS) for 30 days. RESULTS: The cells attached and grew on the scaffolds of all groups. The cell number and the differentiation markers of groups A and B were remarkably higher than those of group C over the observation periods. Slow proliferation of the cells of group A and B in the PR medium in the first 7 days corresponded to the maximum increases in alkaline phosphatase activities (ALP). The maximum levels of ALP of those groups in the OS medium were not detected until day 14. The levels of osteocalcin of those groups were not statistically different when cultured in both mediums. CONCLUSIONS: The MSCM scaffolds are suitable for supporting attachment and growth of the osteoblasts. Additional BCP into the PCL-based scaffolds accelerate early differentiation of the cells in the constructs even without osteogenic-inductive condition. [ABSTRACT FROM AUTHOR]

Determination of phosphate ion (PO 4 3- ) is important in biomedical and environmental arrays because its controlling concentrations are associated with different pathologies or the quality of water. Herein, we report a new type of photoluminescence (PL) probe for highly selective detection of PO 4 3- based on a single-layered graphene quantum dots chelating with aluminium ions (s-GQDs-Al 3+ ) system. The PL of s-GQDs can be enhanced by Al 3+ through the aggregation-induced emission enhancement (AIEE) effect. With the addition of PO 4 3- , the PL of the s-GQDs-Al 3+ system is faded away because PO 4 3- has stronger coordination with Al 3+ which results in the elimination of AIEE effect and the decrease in the PL intensity of the s-GQDs-Al 3+ system. Therefore, the s-GQDs-Al 3+ system can behave as an on-off type PL probe for PO 4 3- detection. It is found that the PL intensity ratio ( I / I 0 ) of s-GQDs in the presence of Al 3+ at 463 nm is proportional to the concentration of PO 4 3- in the range of 0.25–7.5 μM with the limit of detection as low as 0.1 μM. This selective assay has a great application prospect in the complex matrixes owing to its simplicity and specificity for PO 4 3- detection. [ABSTRACT FROM AUTHOR]

Phosphated zirconia prepared by sol-gel method has been used as catalyst in esterification reaction of acetic acid with ethanol. Optimization of different preparation parameters on the catalyst was studied, such as the effect of molar ratio n / n , surfactant assisted synthesis, calcination temperature, and the effect of the drying mode. Catalysts were characterized by N physisorption at −196 °C, X-ray diffraction, FTIR spectroscopy, and P MAS NMR spectroscopy. The obtained results show that an increase in phosphate content partially inhibits the development of tetragonal t-ZrP phase and leads to a rise of both specific area and pore size of the catalyst. Besides, the introduction of the surfactant in the preparation step develops this phase and enhances the size of pores, but decreases specific area. However, calcination of the catalyst allows the development of tetragonal ZrO phase and causes the disappearance of ZrP phase. The evacuation of the solvent at its supercritical conditions promotes the development of both tetragonal phase of zirconia and pore size but slows that of the phases related to the ZrP species. Catalytic properties of acid esterification by ethanol were correlated to catalyst characteristic data, suggesting that t-ZrP phase and doping agent-support interaction stabilize active sites of the catalyst. Kinetic and mechanism study shows that catalytic reaction occurs with a first order and takes place through Eley-Rideal mechanism in which adsorbed acetic acid species react with ethanol in fluid phase to form corresponding ester. Application of Eyring theory shows that the adsorption step is characterized by an endothermic character and a rapid associative mechanism occurs between adsorbed species and the second reactant. Graphical abstract: Eley-Rideal mechanism of acetic acid esterification by ethanol over xerogel catalyst XZrP [ABSTRACT FROM AUTHOR]

Han, J.-Y.; Lee, J.; Lee, Y.-G., and Jang, A., 2017. Solid-state ion selective lab chip sensor for on-site measurement of orthophosphate in small volumes of liquid. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 50-54. Coconut Creek (Florida), ISSN 0749-0208. This paper described the characterization of the assembled solid-state ion-selective lab chip sensor to potentiometrically measure phosphate ion. Since the assembled chip sensor is easy to setup and does not require any sample preparations, it is an ideal technique to study the measurement of phosphate in small volumes of liquids or in estuarine sediments. The size of the proposed lab chip is 12 mm × 21 mm, and the microfluidic channel has the width of 2 mm, length of 5 mm, and depth of 150 μm. All electrodes have the length of 500 μm, width of 200 μm, and spacing of 200 μm. The potential response of the assembled phosphate ion-selective lab chip sensor showed a linear regression in the range of 1×10−5 to 1×10−3 M with a slope of 54 mV/decade. In addition, the experimental results showed a good precision, indicating that relative standard deviation (RSD) was 3.5%. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: Rough endoplasmic reticulum is important organelle that plays a role in the regulation of a range of functions. Potassium channels in the endoplasmic reticulum membrane were recently reported that its physiological role is unknown. Hepatocyte endoplasmic reticulum is a rich source of glucose 6- phosphatase that is involved in the control of gluconeogenesis. Since phosphate ions are intra-luminal metabolites for this enzyme of endoplasmic reticulum thus, in this study, the effect of phosphate ions on potassium channel activity was studied.METHODS: Endoplasmic reticulum vesicles extraction was accomplished following liver excision in rats, homogenization and several stages of ultracentrifugation. Phosphatidylcholine was extracted from fresh egg yolk. Bilayer lipid membrane was formed in a 350 µm diameter aperture in between two chambers cis and trans contained 200/50 mMKCl solutions respectively, then vesicles were incorporated into bilayer lipid membrane. Ion channel activity was recorded by single channel recording technique both in control conditions and presence of phosphate ion in luminal face, next biophysical ion channel properties analyzed by Clampfit10 software.FINDINGS: Endoplasmic reticulum Potassium channel was 550 pS conductance and its activity changed as voltage dependent manner in voltage range of +30 to -40 mV, in this respect the open probability and the average unitary current in a voltage + 30 mV were 0.73 and 26 pA, respectively. However, at lower voltages, the channel activity was minimal. In the presence of 50 mM phosphate ion, mean unitary current and also channel open probability did not change significantly in different voltages compared to the control condition (p>0.05).CONCLUSION: Rat hepatocyte endoplasmic reticulum membranes has been a kind of potassium channel with voltage-dependent activity and it seems that its electrophysiological characteristics did not influenced by phosphate anion in luminal face.

Different molar ratios of a Ni/Co binary hydroxide (NiCo82, NiCo91, and Ni100) were prepared and calcined at 270 °C (NiCo82-270, NiCo91-270, and Ni100-270). The properties of the adsorbents and the amount of adsorbed phosphate ions were evaluated. The adsorbents calcined at 270 °C had a nickel oxide structure. The amount of adsorbed phosphate ions, the amount of hydroxyl groups, and the specific surface area of the calcined adsorbents at 270°C were greater than those of the uncalcined adsorbents. The amount of adsorbed phosphate ions was related to the amount of hydroxyl groups and the specific surface area; the correlation coefficients were 0.966 and 0.953, respectively. The adsorption isotherm data for NiCo91 and NiCo91-270 were fit to both the Freundlich and Langmuir equations. The amount of adsorbed phosphate ions increased with increasing temperature. The experimental data fit the pseudo-second-order model better than the pseudo-first-order model. A neutral pH was optimal for phosphate ion adsorption. In addition, the phosphate ions that were adsorbed onto NiCo91-270 could be recovered using sodium hydroxide, and the adsorbent was useful for the repetitive adsorption/desorption of phosphate ions. Collectively, these results suggest that NiCo91-270 is prospectively useful for the adsorption of phosphate ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

A coumarin based simple fluorescent “turn-on” probe, 4-Hydroxy-3-[(2-hydroxy-5-methoxybenzylidene)-amino]-chromen-2-one ( HMC ), to detect metal ion based on the chelation enhanced fluorescence (CHEF), was synthesized by condensing 3-amino-4-hydroxycoumarin and 2-hydroxy-5-methoxybenzaldehyde. It was found to be highly selective and sensitive sensor for Al 3+ in 90% aqueous methanol (MeOH: 0.01 M HEPES Buffer; 9:1; v/v) at pH 7.4 in fluorescence spectroscopy. Fluorescence intensity enhancement along with 10 nm blue shift was observed only in the presence of Al 3+ . The HMC binds Al 3+ in 1:1 stoichiometry with a binding constant, K a = (9.9 ± 0.04) × 10 3 M −1 and the detection limit was calculated to be as low as 1.62 μM. The binding mode of interaction with Al 3+ and the chelate complex formation was supported with the help of a 1 H NMR spectroscopy titration, ESI–MS and also by theoretical studies. Moreover, the HMC ·Al 3+ ensemble subsequently detected the biologically important phosphate ions and nucleotides via fluorescence quenching. The live cell imaging study indicated that HMC is highly efficient in the detection of exogenous Al 3+ in living cell. [ABSTRACT FROM AUTHOR]

We report a novel magnetic relaxation-based sensing method for sensitive and selective detection of phosphate ions in aqueous media using paramagnetic nanoparticles. The method can detect phosphate ions at physiological pH quantitatively with high selectivity, even in a commercial fertilizer without separation. [ABSTRACT FROM AUTHOR]