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To improve the safety of HMX, HMX/NH2-GO composite was prepared with aqueous ammonia functionalized graphene oxide (NH2-GO). The composite was characterized by SEM, Zeta potential, XPS, Raman spectrum, XRD, HPLC, DSC and BAM sensitivity test. The results indicated that the functionalization with aqueous ammonia can enhance the interaction between GO and HMX, and more efficiently desensitize the explosive. The optimal impact sensitivity of the HMX/NH2-GO composite can be not less than 40 J, which is also the most insensitivity compared to the previous reports prepared by coating desensitization with non-energetic desensitized material. Moreover, the potential reason for the different impact and friction sensitivity was also discussed, which may bring a novel perspective to achieve the desensitization of energetic material.

Inefficient flotation of bastnaesite remains a challenge in the production of rare earth elements. This study aimed to investigate the dissolution and adsorption behaviour of species that are commonly released into bastnaesite flotation pulp from Ca/Ba-bearing gangue minerals. The influence and corresponding mechanisms on the bastnaesite mineral surface and collectors, namely sodium oleate (NaOL), were evaluated experimentally based on micro-flotation, zeta potentials, in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-Ray photoelectron spectroscopy (XPS) analyses. The flotation recovery of bastnaesite significantly decreased from ∼95% to ∼25%, ∼15%, ∼80%, ∼25% when exposed to calcite, fluorite, barite, and mixed dissolved species, respectively. The zeta potential of bastnaesite was pH sensitive, indicating that H+ and OH− determine the surface potential of bastnaesite. Solution chemistry analyses revealed that the presence of the dissolved species differed at various pH values. In situ ATR-FTIR demonstrated the different effects of the dissolved species from calcite, fluorite, and barite on collector adsorption. The former two dissolved species mainly depressed the chemisorption of the NaOL monomers (RCOO‒), whereas calcite also affected the physical adsorption of the oleic acid molecular dimer (RCOOH·RCOO‒). Moreover, the barite dissolved species only affected the physical adsorption of the NaOL species. The results of XPS analysis revealed that dissolved species from these three gangues could pre-adsorbed onto bastnaesite and affected the interaction with the collector. Density functional theory calculations were employed to provide further theoretical insights into the interactions between the dissolved species from calcite, fluorite, and barite and NaOL.

Nanozymes are inorganic nanoparticles with enzyme-like features. Noble metals and metal oxide-based nanomaterials can present enzyme-mimicking behavior mediating catalytic reactions including oxidase-, peroxidase-, catalase-, and superoxide dismutase-like activities with important applications in environmental and biomedical grounds. Thus, in this study, it was designed and developed a novel nanosystem that exploits the oxidase-like (OD) behavior of gold nanoparticles (AuNPs, GOLDzyme) and the peroxidase-like (POD) characteristics of cobalt-doped magnetic iron oxide nanoparticles (MIONs, Co-MIONzyme) amalgamated in an inorganic-inorganic bi-nanozyme cascade for the degradation of dye pollutants. GOLDzyme and Co-MIONzyme nanomaterials were synthesized and stabilized by citrate and carboxymethylcellulose (CMC) ligands, respectively, using a green aqueous colloidal process at mild conditions. The physicochemical characterization results indicated that water-dispersible colloidal supramolecular nanostructures were effectively produced, with core-shell morphologies (i.e., inorganic nanoparticle core/organic-shell). The AuNPs (GOLDzyme) presented crystalline nanostructure, with a uniform spherical shape, zeta potential (ZP) = - 46 ± 3 mV, hydrodynamic diameter (DH) = 11 ± 3 nm. Analogously, the Co-MIONzyme stabilized by CMC ligand evidenced the formation of nanocrystalline substituted magnetite (CoxFe3-xO4) with uniform spherical morphology, average size = 7.0 ± 2 nm, ZP = - 47 ± 3 mV, DH = 46 ± 3 nm, and superparamagnetic behavior. When tested separately using a colorimetric assay based on a chromogenic molecule (3,3',5,5’ tetramethylbenzidine, TMB), they demonstrated catalytic activity upon the injection of each specific substrate in the medium, i.e., glucose for GOLDzyme that behaved predominantly as oxidase-like nanomaterial, and H2O2 for Co-MIONzyme, which showed a peroxidase-like or catalase-like behavior. In addition, these nanozymes demonstrated pH-dependent and temperature-dependent catalytic activities. As a proof of concept, when combined into a single-pot reaction system, these bifunctional nanozymes confirmed integrated catalytic cascade as oxidase and peroxidase-like nanocatalysts towards the oxidation of TMB and the degradation of methylene blue (MB, ~18%) as the model dye pollutant. Based on the preliminary encouraging results of this research, it can be foreseen that the combination of nanozymes paves the way for the development of new nanoplatforms for prospective applications in water treatment and environmental remediation.

Rare earth elements (REE) are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention. However, the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system. In this study, the species distribution of REE within the pH 0 to 8.0 was calculated. The SBA-15 originated from coal fly ash was modified by two steps with (3-Aminopropyl) triethoxysilane (APTES) and diethylenetriaminepentaacetic dianhydride (DTPADA) to obtain DTPADA-SBA-15 adsorbent, which was applied to the selective adsorption of REE. The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE, including Eu, Gd, Tb, Nd and Sm, in acidic solution (pH 2) with multi competing ions. The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value. The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudo-second-order kinetic, of which the adsorption process followed the Langmuir isotherm model.

Bastnaesite is an important rare earth mineral and is usually beneficiated by flotation. Sodium silicate is commonly used to depress calcium-bearing gangue minerals, however it can also depress bastnaesite when Ca2+ ions exist in the pulp. In this study, the effect of Ca2+ ions and sodium silicate individually or in combination on bastnaesite flotation was studied through micro-flotation, zeta potential, fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements. Micro-flotation results show that the combination of Ca2+ ions and sodium silicate depresses bastnaesite more severely due to their synergistic effect. Zeta potential results show that the combination renders the surface potential of bastnaesite negatively shifted more significantly. Fluorescence spectroscopy shows that the combination decreases the surface hydrophobicity of bastnaesite more severely. XPS shows that the combination increases the adsorption of sodium silicate on bastnaesite by forming hydrophilic Ca-SiO3 precipitate, which causes more serious depression on bastnaesite flotation.

In spite of the promising properties of small interfering RNAs (siRNAs) in the treatment of infectious diseases, safe and efficient siRNA delivery to target cells is still a challenge. In this research, an effective siRNA delivery approach (against HIV-1) has been reported using targeted modified superparamagnetic iron oxide nanoparticles (SPIONs). Trimethyl chitosan-coated SPION (TMC-SPION) containing siRNA was synthesized and chemically conjugated to a CD4-specific monoclonal antibody (as a targeting moiety). The prepared nanoparticles exhibited a high siRNA loading efficiency with a diameter of about 85 nm and a zeta potential of +28 mV. The results of the cell viability assay revealed the low cytotoxicity of the optimized nanoparticles. The cellular delivery of the targeted nanoparticles (into T cells) and the gene silencing efficiency of the nanoparticles (containing anti-nef siRNA) were dramatically improved compared to those of nontargeted nanoparticles. In conclusion, this study offers a promising targeted delivery platform to induce gene silencing in target cells. Our approach may find potential use in the design of effective vehicles for many therapeutic applications, particularly for HIV treatment.

Monazite ((Ce, La)PO4) is one of the major types of light rare earth minerals from which the light rare earth elements cerium (Ce) and lanthanum (La) are economically extracted. Flotation is extensively used to recover fine-grained monazite. Sodium oleate (NaOL) is considered as the collector with the strong collecting ability for monazite flotation. However, this study shows that its collecting ability is still limited. In this paper, a phosphonic acid, nonane-1,1-bisphosphonic acid (C9-BPA), was employed as the novel collector in place of NaOL. Flotation experiments show that even when the C9-BPA dosage is less than one-fifth of the NaOL dosage, the monazite recovery using C9-BPA as the collector is approximately 22 wt% higher than that using NaOL. The mechanism by which C9-BPA adsorbs on monazite was investigated using zeta potential, infrared (IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements as well as first-principles calculations. Zeta potential measurements show a more significant decrease in the zeta potentials of monazite after the addition of C9-BPA compared to those after the addition of NaOL. For C9-BPA-treated monazite, the characteristic peaks of C9-BPA were observed in the IR and C 1s XPS spectrum, whereas for monazite treated by NaOL, no characteristic peak of NaOL was observed. Experimental results show that C9-BPA has a stronger affinity towards the monazite surface than NaOL as confirmed by the higher adsorption energy of CP-BPA on the monazite surface (‒204.22 kJ/mol) than NaOL (‒48.48 kJ/mol). This study demonstrates an extensive application value and prospect of C9-BPA in monazite flotation and helps design novel collectors with strong collecting ability for monazite flotation.

Pulsed chemical vapor deposition (P-CVD) is a promising technology for the surface modification of TiO2 particles. For the scale-up application of P-CVD, a custom-designed rotary reactor and corresponding coating process at room temperature was developed in the present work. The obtained SiO2-coated TiO2 particles were characterized by various measures including high-resolution transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, etc. The results illustrated that the SiO2 films with a thickness of (3.7±0.7) nm were successfully deposited onto the surface of TiO2 particles. According to the dye degradation tests and acid solubility measurement, the deposited film can effectively inhibit the photocatalytic activity and enhance the weatherability of the TiO2 particles. Zeta potential measurements showed that the SiO2-coated TiO2 is possible to be stably dispersed in the pH range of 6.9–11.6. The coating process made the whiteness of TiO2 particles decreased slightly but still sufficient (97.3±0.1) for application. Furthermore, the properties of the TiO2 particles coated by P-CVD were compared with the particles coated by traditional wet chemical deposition. It is shown that the P-CVD can produce thinner but denser films with better photoactivity suppression performance. The developed coating process within the rotary reactor was proved practically feasible and convenient for the scale-up production of SiO2-coated TiO2 via P-CVD.

Achieving the desired efficiency in cuttings transport has always been a challenge during drilling situations due to complex wellbore trajectories and drilling hydraulics. These issues require suitable additives to formulate the drilling muds. Hence, nanocomposite (NC) particles formed from silica and polypropylene was modified by (3-Aminopropyl) triethoxysilane (termed PP-SiO2 NC-NH2) and the impact of the concentrations of the PP-SiO2 NC-NH2 between 0.4 and 1.2 ppb on the cuttings transport efficiency (CTE) of complex water-based mud (WBM) system was assessed. Mud system containing 0.5 ppb PP-SiO2 NC-NH2 on CTE was measured and compared with that of partially hydrolyzed polyacrylamide (PHPA) using sandstone grains of diameters between 0.50 and 3.20 mm at hole angles 0, 30, 45, 60, and 90° with a 42 L/min pump rate. The zeta potential (ζ-potential), particle size distribution, morphology, and temperature resistance of the NC were examined. The ζ-potential data revealed the stability and the long-term stabilization of the modified NC in drilling muds. By adding the concentration of the modified NC into the WBM system, the thinning characteristics and consistency factors were enhanced as the NC concentration increases. Furthermore, the rheological test program reveals that the NC concentrations and 0.5 ppb PHPA increased the shear stress of the WBM with an increase in the shear rate. However, the mud system of PHPA exhibited a larger viscosity, while the NC samples showed a flat viscosity-profile. Also, the NC demonstrated better cuttings recovery than the PHPA product at 0.5 ppb concentration, especially at the worst hole angle of 45°. The cuttings recovery from a minimum to a maximum was found to occur in this order; 45°, 60°, 30°, 90°, and 0°. In contrast with the smallest and intermediate sand grains, the largest grains have complex and less fluid transport. With a pipe orbital motion of 150 rpm and a pump rate of 42 L/min, the CTE of the muds showed higher improvement. Overall, the mud properties of the modified NC exhibited a strong enhancing impact on the cuttings carrying capacity of the base mud than the PHPA.

Biologically inspired synthesis of nanoparticles was found to be more attractive in metal nanoparticle synthesis. The present study reported an in-situ biogenic synthesis of silver nanoparticles (AgNPs) using Solanum trilobatum aqueous leaf extract. On this basis, the aqueous leaf extract of S. trilobatum acted as a reducing agent and stabilizing agent to synthesize highly stable AgNPs at ambient temperature. Eventually, the synthesized and stabilized AgNPs surface plasmon resonance was near 430 nm through a UV–visible (UV–vis) spectrophotometer. Here, the stability of the silver colloids monitored through zeta potential and mean particle size was evaluated through diffraction light scattering (DLF). Further, the average particle size was found to be 27.6 nm and spherical, confirmed with transmission electron microscopy (TEM). Also, colloidal AgNPs and aqueous extract are found to be rich sources of antioxidants and exhibit higher free radical scavenging ability. Thus, efficient inhibition with COX1 and COX2 enzymes and the protective effect with human red blood cell (HRBC) membrane stability showed significant results. These features, suggesting the possibility of the AgNPs useful to disease-modifying for treating inflammatory disorders and associated complications.

Fly ash (FA) is a complex and abundant solid waste created by humans, and has caused environmental issues, for which flotation is an effective technique employed before its comprehensive utilization. However, the complex and hydrophilic characteristics of FA particles cannot naturally fulfill the selective separation by common flotation. Therefore, this study aims to provide an insight into fluid intensification effects on flotation to achieve the enhancement of FA surface property and decarburization. The relevant effects and mechanisms are investigated, based on the measurements of zeta potential, infrared spectroscopy, contact/wrap angle, induction time, size distribution and scanning electron microscopy–energy dispersive spectrometry. Experimental results manifested that the maximum unburned carbon recovery (73.25%) and flotation rate (0.2037 s–1) were achieved with preconditioning energy inputs of 14.23 and 6.57 W·kg–1 respectively. With increasing preconditioning energy inputs, fluid intensification effects could promote the inter-particle collision/attrition, detachment of hydrophilic existence and collector adsorption on particles. Correspondingly, absorbance of some hydrophobic and hydrophilic functional groups was strengthened and weakened respectively, which accounted for the improved interfacial properties, reflected as the increased contact and wrap angles, together with declined induction time. Overall, this article revealed the positive influences of fluid intensification based preconditioning process on rendering particle surface hydrophobic and improving separation performance.

Filtration control is important to ensure safe and high efficient drilling. The aim of the current research is to explore the feasibility of using basil seed powders (BSPs) to reduce filtration loss in water-based drilling fluid. The effect of BSP concentration, thermal aging temperature, inorganic salts (NaCl and CaCl2) on the filtration properties of bentonite/basil suspensions was investigated. The filtration control mechanism of BSP was probed via water absorbency test, zeta potential measurement, particle size distribution measurement, and filter cake morphologies observation by scanning electron microscope. The incorporation of BSPs into the bentonite suspension generated acceptable rheology below 1.0 w/v%. The BSPs exhibited effective filtration control after thermal aging at 120 °C, but less efficiency at 150 °C. After thermal aging at 120 °C, the bentonite suspension containing 1.0 w/v% BSPs could resist NaCl and CaCl2 pollution of 5.0 w/v% and 0.3 w/v% respectively. Besides general filtration control behaviors, the exceptional water retaining capability formed by numerous nanoscale 3D networks in the basil seed gum and considerable insoluble small particles in BSPs might further contribute to the filtration control. The excellent filtration properties bring basil seed a suitable and green candidate for the establishment of high-performance drilling fluids.

Lipid nanoparticles (LNPs) containing mRNA can deliver genetic material to cells for use as vaccines or protein replacement therapies. We characterized the effect of solution pH on cationic LNPs containing green fluorescent protein (EGFP) mRNA and their transfection efficiency. We compared the structural and colloidal properties of mRNA LNPs with LNPs not containing mRNA and mRNA free in solution. We used a combination of biophysical technique to build a picture of the structure of the lipids and mRNA across pH and temperature in the form of an empirical phase diagram (EPD). A combination of Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry was used to investigate lipid phase behavior. The mRNA–LNPs transition from an inverse hexagonal phase at pH values below the pKa of the cationic lipid to a lamellar phase above the pKa. At higher temperatures the mRNA–LNPs also transitioned from an inverse hexagonal phase to a lamellar phase indicating the inverse hexagonal phase is more thermodynamically favorable. Based on circular dichroism, the mRNA within the LNP has more A form structure at pH values below the lipid pKa than above it. Optical density, zeta potential and dynamic light scattering measurements were used to probe the colloidal stability of the mRNA–LNPs. The particles were larger and more prone to aggregation below the pKa. A stability study was performed to relate the biophysical characteristics to the storage of the particles in solution at 4 and 25 °C. mRNA–LNPs had the highest transfection efficiency and stability at pH values below the pKa. However, there was a trade-off between the stability and aggregation propensity since at very low pH the particles were most prone to aggregation. We performed kinetic experiments to show that the time scale of the pH-dependent phase behavior is slow (6 hour transition) and the transition from lamellar to inverse hexagonal phases is irreversible. This suggests that the lamellar phase is less stable and kinetically trapped. Our findings deepen our structural understanding of mRNA–LNPs and will aid the development of related formulations.

This study examines the electrophoretic deposition of Yb2Si2O7 particles on SiC substrates to produce Environmental Barrier Coatings. To prepare crack-free and homogeneous green coatings, the effect of the solvent, dispersant concentration, and pH were investigated. Ethanol provided a well-dispersed suspension and crack-free coating which was shown by sedimentation tests and microstructure analysis. The effect of the dispersant concentration was investigated with zeta potential measurement and microstructure analysis with a concentration above 0.5 g/L resulting in higher ionic strength and producing cracked and uneven coatings. The ionic strength was also associated with the powder packing density with larger indentation impressions measured for loosely packed coatings. The deposition rate depended on the suspension properties influenced coating integrity with delamination evidenced by analysing the current density drop during deposition. Sintering of the green coatings having different densities and microstructure showed their importance in the preparation of uniform and dense sintered coatings.

Hypoxia and high-density extracellular matrix within the tumor microenvironment (TME) strengthens tumor resistance to the oxygen-dependent cancer therapy. Herein, an on-demand oxygen released nanoplatform (MONs/IR780/PFC-O2@BSA, BMIPO) that was triggered by near-infrared (NIR) light combined with TME has been designed for achieving synergistic photothermal/photodynamic therapy with deep intratumoral penetration and oxygen self-sufficiency. Notably, the zeta potential and transmission electron microscope (TEM) results indicated that such "smart" BMIPO nanoplatform possessed good colloidal stability and on-demand TME-specific degradability. This characteristic of the BMIPO nanoplatform allows it to simultaneously achieve high tumor accumulation and deep intratumoral penetration. The results of the O2 loading and release measurements showed that the as- prepared BMIPO possessed excellent O2 reversibly bind/release performance. Furthermore, the photothermal effect of NIR dye (IR780) accelerated the dissociation of TME-responsive BMIPO, as a result, it achieved an on-demand, continuous and complete O2 release to relieve tumor hypoxia during phototherapy. In vitro and in vivo results demonstrated that the as-prepared all-in-one nanoplatform have successfully realized NIR-triggered on-demand O2 release, nanocarrier-mediated glutathione (GSH) reducing, hyperthermia-promoted deep intratumoral penetration and dual-model imaging-guided precise cancer therapy. This work would provide inspiration for the design of nanoplatforms with on-demand release and deep intratumoral penetration for achieving high-efficiency synergistic photothermal/photodynamic therapy in hypoxic tumors.

Despite the broad range of interest and applications, controls on the electric surface charge and the zeta potential of silica in contact with aqueous solutions saturated with dissolved CO2 at conditions relevant to natural systems, remains unreported. There have been no published zeta potential measurements conducted in such systems at equilibrium, hence the effect of composition, pH, temperature and pressure remains unknown. We describe a novel methodology developed for the streaming potential measurements under these conditions, and report zeta potential values for the first time obtained with Fontainebleau sandstone core sample saturated with carbonated NaCl, Na2SO4, CaCl2 and MgCl2 solutions under equilibrium conditions at pressures up to 10 MPa and temperatures up to 40 °C. The results demonstrate that pH of solutions is the only control on the zeta potential, while temperature, CO2 pressure and salt type affect pH values. We report three empirical relationships that describe the pH dependence of the zeta potential for: i) dead (partial CO2 pressure of 10-3.44 atm) NaCl/Na2SO4, ii) dead CaCl2/MgCl2 solutions, and iii) for all live (fully saturated with dissolved CO2) solutions. The proposed new relationships provide essential insights into interfacial electrochemical properties of silica-water systems at conditions relevant to CO2 geological storage.

By surface modification with APTMS, spontaneous coagulation casting (SCC) of fused silica based on Isobam was achieved and the possible coagulation and molding mechanism is proposed. Through the interaction between the polar groups on the Isobam molecular chain and the incorporated –NH2 groups on the surface of the silica particles, Isobam molecular chains were adsorbed on the surface of particles, which initiate the formation of flocs and the solidification of the suspension. The addition of dispersant TMAH results in the hydrolyzation of Isobam, forming more –COO–, which effectively improves the fluidity and stability of the suspension. Then the zeta potential, rheological properties and coagulation behavior of the suspension were systematically investigated and the fused silica suspension with high solid content (up to 52 vol%), low viscosity and good coagulation properties were prepared at 1.8 wt% TMAH and 0.5 wt% Isobam dosage. After sintering at 1260 °C for 4 hours, the fused silica ceramics (50 vol% solid content) shows a high bending strength of 61.59 MPa, the lowest dielectric loss tanδ of 8.46 × 10-4 and the dielectric constant of 3.72. Thus, this work provides a simple and effective method for preparing fused silica and other ceramics with negative surface charge by Isobam SCC.

In the present work gold nanoparticles were synthesized by green method using Aegle marmelos bark extract and the reaction conditions were optimized. Synthesized nanoparticles were characterized by using different analytical techniques including UV–Visible spectroscopy, FTIR (Fourier Transform Infra Red) spectroscopy, TEM (Transmission electron microscopy), DLS (Dynamic Light Scattering) and Zeta Potential Analyser. The Biosynthesized gold nanoparticles were then used for colorimetric detection of Cr(III) and Al(III) from aqueous medium. It was found that the detection limit with nanoparticles was as low as 0.5 mM for Cr(III) ion and 0.01 mM for Al(III) ions in aqueous medium.

The present work investigates analytically an electroosmotic flow (EOF) of a Newtonian liquid in a microchannel between two parallel plates. Homotopy perturbation method (HPM) is used to solve the constitutive governing equations. The Poisson-Boltzmann equation for electrical potential distribution is considered. Present work disregards the Debye–Huckel approximation to minimize exactness of present results. Consequently, using the electric potential profile obtained, a modified Navier–Stokes equation is solved for velocity distribution. The energy equation is also altered based on scale analysis to find temperature distribution. Finally, based on the temperature profile Nusselt number is determined. The proposed results are shown in comparison with a numerical and an established result which considers the Debye–Huckel approximation. It is seen that the present results agree well with the numerical predictions for a varied range of zeta potential. But, the established conventional method differs from the numerical result for higher range of zeta potential. Nusselt number is evaluated and shown as function of the electrokinetic length for different zeta potentials. The work finally concludes that the proposed model can be applied for predicting EOF in microchannels for wider range of zeta potential.

Heavy metal-containing wastes pose long-term environmental threats. In the present work, cementitious binders in the presence of halloysite nanotubes (HNTs) at 1 wt%, 3 wt%, and 5 wt% by mass were used to immobilize lead (Pb(II)). Semi-dynamic leaching tests were used to quantify the Pb(II) leaching up to 64 days. The results showed that the addition of 1 wt%, 3 wt%, and 5 wt% HNTs particles strongly reduced the Pb(II) release. The optimal dosage of HNTs was 3 wt%, which decreased the cumulative release of Pb(II) by around 40.5% after 64 days. Isothermal calorimetry, X-ray diffractometry (XRD), thermogravimetry (TG), mercury intrusion porosimetry (MIP) and compression tests were then used to investigate better immobilization effect with HNTs addition. The results showed that HNTs particles promoted cement hydration, refined the pore structure of the hardened cementitious binders, decreased permeability, and enhanced mechanical strength. Zeta potential measurements indicated that the negative surface charge of the HNTs particles could adsorb Ca2+ ions from the pore solution of cement hydration, then facilitating adsorption of Pb(OH)3−.

CAPE found in propolis has become the subject of research interest as it has various medicinal benefits such as antiviral, anti-inflammatory, antioxidant, anticancer and immunomodulatory properties [1] . In this study, propolis obtained in Kuantan, Pahang is encapsulated using biodegradable polymer, vitamin E TPGS as a drug delivery system whereas TPGS-CAPE is used as a control. The findings show the physical characterization of propolis loaded vitamin E TPGS polymeric micelles which includes size, polydispersity index, zeta potential, shape and morphology and encapsulation efficiency.

Psoriasis is an inflammatory skin which is chronic disorder with epidermal (acanthosis) hyperplasia and extreme inflammation as erythematous lesions. The penetration and neovascularization of inflammatory cells resulting from epidermis hyperproliferation with incomplete keratinocyte differentiation irregular horn cell formation are characterized by an erythematous scaly skin plaque. The purpose of the work entitled was to increase the penetration of the drug and develop nanoparticle loaded gel for better in-vitro release. Erlotinib belongs to BCS class II that stands for high permeability and less solubility. On physicochemical evaluation, melting point of erlotinib had been established to be 229.4 ± 254.6 °C. On UV analysis absortion maxima was found to be 341 nm in 0.1 N HCl. The Erlotinib shown very good solubility in ethanol, diethyl ether in contrast showed less solubility in phosphate buffer and water. An attempt is made to prepare nanoparticle gel of erlotinib using lipid such as cetyl palmitate poloxamer 188. The method of preparation of nanoparticles was found to be simple and reproducible. The formulated nanoparticles had been specified for its particle size and it comes out to be 81.57 ± 9.6 nm and zeta potential was found to be −29.3 ± 1.21mV. Percentage entrapment efficiency was found in a range of 89.2 ± 21% and loading efficiency was found to be 13.45 ± 0.72. The in vitro drug release of erlotinib from method ET-NLC15 become satisfactory give an explanation for with the aid of using Higuchi equation. This indicates that ET-NLC15 gel follow matrix diffusion-based release kinetics and the highest regression coefficient (R2) value was 0.968 through Higuchi model. Hence from all aspects; we concluded that the release of drug Erlotinib can provide drug release in a controlled manner by proper designing of the formulation and selection of a suitable method of preparation.

Molecularly imprinted polymers (MIPs) having the potential to mimic the selectivity and sensitivity of biological molecular recognition are blended here with piezoelectric transducer (EQCM) able to provide ‘real time’ monitoring of molecular level events with extreme sensitivity. In this work, molecularly imprinted polymer nanoparticles selective for a psychoactive drug, cathinone were synthesized, characterized and applied for specific and selective uptake in water. Nanoparticles were separated by centrifugation and characterized for their size and zeta potential. p-Phenylene diamine was chosen as functional monomer to imprint S-cathinone via in silico studies. Molecularly imprinted nanoparticles were eletrodeposited on gold coated quartz crystal electrode of electrochemical quartz crystal microbalance (EQCM). Molecular imprinting experiments were optimized for selective and specific uptake of S-cathinone. Thus fabricated EQCM sensor was able to discriminate between stereoisomers and other close structural analogues also. Imprinting data were successfully fitted to Freundlich adsorption isotherm and curves for non-imprinted and imprinted data were compared. Under optimized conditions, response of nanoMIP-EQCM sensor is linearly proportional to S-cathinone concentration with detection limit as 0.12 ng mL−1 and quantification limit as 0.409 ng mL−1 and imprinting factor as 8. Hence, a highly specific and selective nanoMIP-EQCM sensor is fabricated in a facile manner.

Nanocellulose from oil palm mesocarp fiber (OPMF) was isolated using hydrothermal treatment at a pressure of 150 kPa and 120 °C coupled with hydrolysis of low concentration of weak acid i.e. oxalic acid dihydrate (OAD). Two different concentrations of OAD i.e. 11 and 13 wt% were introduced in the acid hydrolysis process. Crystallinity index of the raw fiber increased from 39.5 to 70.4 and 70% for 11 and 13 wt% OAD, respectively. The average particles sizes of nanocellulose measured using TEM was approximately 25 nm for both concentrations of OAD which approximately equivalent to the one measured using dynamic light scattering (DLS). The values of zeta potential of the nanocellulose suspension isolated using 11 and 13 wt% OAD were −26 and −27.5 mV respectively. Isolation technique which is hydrothermal treatment coupled with low concentration of OAD was effective in producing OPMF nanocellulose at high crystallinity index, less than 100 nm size distribution, and it is a stable suspension.

Liquid crystalline nanoparticles (Cubosomes) are unique structures for the effective delivery of many pharmaceutical drugs. The present study is aimed to develop and characterize novel cubosomal formulation containing dexamethasone (DMS). The cubosomes were incorporated into hydrogel for prolonged delivery of DMS to treat vitiligo. The cubosomes were prepared via top-down technique using different concentrations of glyceryl monooleate (GMO) (lipid phase), poloxamer 407 (P 407) (non-ionic surfactant), oleic acid (fatty acid) and water (aqueous phase). The formulated cubosomal formulations were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), zeta size analyzer for their surface morphology, particle size and zeta potential. Further, they were evaluated for % entrapment efficiency and in-vitro drug release. The optimized F-12 formulation exhibited a particle size of 250.40 nm and a zeta potential of −36.10 ± 2.56 mV. The in-vitro drug release of 88.12% was achieved at 12th h. The F-12 formulation was incorporated into 1% carbopol 940 to form cubogel (CG). The F-12 loaded CG was evaluated for physical characteristics, pH, drug content, viscosity, spreadability, and in-vitro drug release studies. All the evaluation parameters for the CG formulation were said to be within the standard limits. The in-vitro drug release for DMS loaded CG was found to be 83.58% at end of 12 h, thus indicating its potential as a better sustained drug delivery system for vitiligo.

Silver nanoparticle (AgNP) synthesis using microalgae is a promising low-cost sustainable alternative. High CO2 tolerant microalgae have not yet been explored for this application. This study pretends to determine the potential of an environmental green algae Desmodesmus abundans acclimated to low and high CO2 (LCA and HCA strains, respectively) as a platform for AgNPs synthesis and evaluate the effect of pH (5, 7.5, 11) and biological component (cells, supernatant and both components) in comparison to a collection strain Spirulina platensis. Exponential grown cultures were centrifuged, the pellet resuspended in 10 mM AgNO3 prepared in water or supernatant at different pH and incubated for 40 h (24 °C, continuous light). After, the filtrated solution was characterized using UV–visible absorption spectra, Zetasizer and scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy. Results showed drastic differences between strains. No nanoparticles were observed with strain LCA, except at pH 11 using the pellet, which generated large particles (127.8 ± 14.8 nm diameter, −26.7 ± 2.4 mV zeta potential). In contrast, the HCA strain in these conditions showed the smallest AgNPs with the lowest zeta potential (14.9 ± 6.4 nm, −32.7 ± 5.3 mV). When the supernatant was conserved, HCA exhibited AgNPs in all pH solutions, with smallest sizes at pH 11 (27.7 ± 14.0 nm, −20.0 ± 1.8 mV). In addition, the HCA supernatant alone showed reducing potential for AgNP synthesis (51.8 ± 20.7 nm, −17.4 ± 1.3 mV). S. platensis also generated AgNPs in all conditions, but nanoscale particles were observed only at pH 11 (18.3 ± 7.5 nm, −33.9 ± 2.4 mV). In conclusion, high CO2 atmospheres seem to potentiate AgNPs synthesis by microalgae with interesting properties accordingly to biological component employed, representing a potential byproduct in CO2 mitigation systems.

When blood comes in contact with dialyzer membranes, the interfacial bioactivation reactions occurring at blood/membrane boundaries detect the gross mechanism of thrombogenicity. In the presence of biocompatible polymers, the adhesion and subsequent interactions of platelets, as well as other serum components (e.g., proteins), are altered. It delays thrombus formation. In this study, the hemocompatibility of polyvinylpyrrolidone (PVP) modified polyethersulphone (PES) hemodialysis membrane fabricated using UV-assisted photochemical synthesis was investigated. To obtain varying degrees of PVP modification on each membrane, each coated surface was aged within the viscous polymer suspension for a predetermined duration. The correlation between the membrane induced hemocompatibility with membrane roughness, chemical composition, and surface charge at different aging duration of coating. In our study, we performed a comprehensive investigations on membrane morphology, hydrophilicity and its chemical composition using Atomic Force Microscopy (AFM), Fourier Transform Infra-Red (FTIR) Spectroscopy, Nuclear Magnetic Resonance (NMR), Zeta potential, and Scanning Electron Microscopy (SEM). The coated samples were analyzed using Luminex assays for the inflammatory biomarkers of Serpin/Antithrombin-III, C5a, 1L-1α, 1L-1β, IL6, and C5b-9. Modified membranes showed significant resistance against fibrinogen adsorption compared to their bare membrane counterpart. This inherent antifouling activity against fibrinogen adsorption was observed more on modified membranes that aged longer within the PVP suspension during synthesis. A longer ageing period contributed to the enhanced PVP modification, hence, more stable polymeric hydration layers. In addition, both bare and coated membranes triggered both complement system activation and inflammatory responses, but to a mild degree in the latter case. Coated membranes at longer coating duration, around ∼4 minutes, had smoother surfaces and lower magnitudes of surface charge and consequently exhibited reduced release of all biomarkers (except IL-1α), indicating enhanced biocompatibility. Higher levels of C5a were observed in membranes coated at 1 and 2 minutes, promoting modest reduction toward the release of other components.

Frozen aquatic products undergo unavoidable quality changes owing to temperature fluctuations during frozen storage and distribution. This study investigated the effects of 1% cellobiose (CB), and 0.5 and 1% carboxylated cellulose nanofibers (CNF) on ice crystal growth and recrystallization of frozen large yellow croaker fillets exposed to temperature fluctuations. Denser and more uniformly distributed ice crystals were observed in the CB- and CNF-treated samples than in the water-treated samples. Furthermore, the addition of CB and CNF suppressed the conversion of bound water to frozen water in the samples during temperature fluctuation cycles, played a positive role in fixing the ionic and hydrogen bonds that stabilize the protein structure, limited the conformational transition from α-helix to β-sheet, and improved protein thermal stability. Based on turbidity, zeta potential, and confocal laser scanning microscopy (CLSM) analyses, the presence of CB and CNF restricted the protein aggregation. Compared with CB, CNF molecules with abundant carboxyl functional groups and longer morphology exhibited better cryoprotective effects. Moreover, the fillets were more improved protected from mechanical damage induced by large ice crystals at a higher CNF concentration. This study reveals the potential of CB and CNF as novel cryoprotectants.

Stable dispersion of nanoparticles in electrolytes is essential for preparing a wide range of advanced electroless nanocomposites. However, nanoparticles agglomerate if the van der Waals attractive forces prevail over the electrostatic repulsive forces. As a result, various surfactants (anionic, cationic, and non-ionic) were used to prevent nanoparticle agglomeration in the electroless plating bath. This study specifically examines the dispersion stability of zinc oxide (ZnO) nanoparticles in an electroless bath with different surfactants, including anionic sodium dodecyl sulfate (SDS), cationic cetyltrimethylammonium bromide (CTAB), and non-ionic polyvinylpyrrolidone (PVP). The zeta potential and hydrodynamic diameter measurements were utilized as an indicator of nanodispersion stability. The results showed a better-dispersed state of ZnO nanoparticles with SDS surfactant with a small average size of the agglomerate. Surfactants SDS and CTAB improved stability by electrostatic repulsion between ZnO nanoparticles whereas PVP by steric inhibition towards other particles. In addition, ultraviolet–visible absorbance spectroscopy (UV–Vis) was used to examine the dispersion stability of ZnO nanoparticles with different surfactants. The nano-ZnO distributed with SDS displayed a maximum percentage of absorbance, suggesting the homogeneous dispersion of ZnO nanoparticles.

Background Nowadays, the non-steroidal drug diclofenac sodium (DCF) has emerged as hazardous pollutant due to its eco-toxic nature and its efficient elimination from wastewater is emerging as crucial problem. But, low activity, high cost and instability of the conventional photocatalysts restrain their uses. Method In this study, different anion impreganted Cu-Al layered double hydroxides (LDH) and Bi2O3 derived heterocomposites have been examined as plausible photocatalysts for degradation of DCF under visible light radiation. These composites have synthesized by simple wet impregnation methods and characterized by several methods such as XRD, HR-TEM, XPS SEM-EDX, XPS, DRS, phototuminescence(PL), BET etc. Significant Findings The BET sorption isotherms indicate that the anion loaded composites are having larger specific surface area than the pristine one. Also, upon anion impregnation the zeta potential values shift towards more negative values confirming absorption of anions. They show significantly higher (65% for carbonate and 83% for sulphate) photcatalytic activity compare to the parent hybrid (53%). Here, the anions act as efficient electron scavengers to suppress the electron-hole pair recombination. The individual photocatalytic reactions follow pseudo-first order kinetics. Due to low cost, simpler preparation, enhanced activity and recyclability the anion loaded derivatives can emerge as excellent photocatalyst for eradicating DCF.

Bio-ingredients (animal urine and honey) assisted synthesis of Fe doped ZnO nanostructures has been reported. The structural, optical, morphological, and thermal properties of Fe–ZnO nanostructures were investigated using XRD, FTIR, FESEM, TEM, and TGA. The average crystallite size of Fe–ZnO nanostructures made with animal urine is 34.2 nm, while those made with honey have an average crystallite size of 8.8 nm. It indicates that the size of Fe–ZnO nanostructure crystallites was determined in part by reaction time. FESEM was used to verify the nanostructures of the spherical shaped nanoparticles, and the honey Fe–ZnO sample showed a uniform distribution of particles. EDX analysis confirmed the existence of Zinc (Zn), Iron (Fe), and Oxygen (O) in the synthesized sample. According to TEM photos of Fe–ZnO nanostructures, the particle size of the samples is well correlated with the crystallite size determined by XRD. The thermal stability of Fe–ZnO nanostructures, as well as the effect of these natural ingredients on thermal stability, has been investigated. The surface charge and Zeta potential value of Fe doped ZnO nanoparticles using honey and Animal urine have been analyzed. The obtained values confirm the honey used Fe–ZnO nanoparticles has higher stability (−22.7 mV) than the animal urine assisted sample (−10.1 mV).

Pomegranate peel polyphenols (PPP), which are natural, safe, and green antibacterial agents, were introduced and embedded in chitosan to form stable nanoparticles. The PPP@chitosan nanoparticles (PPP@CNPs) were further electrospun into nanofibers based on Pleurotus eryngii polysaccharide (PEP). The preferable distribution of particle size, polydispersity index, and zeta potential was realized through the addition of PPP at 3 mg/mL, which achieved the highest encapsulation rate of 23.71 ± 0.51%. The tensile strength and elongation at break of nanofibers reached 15.76 MPa and 0.69% with the addition of 1% PEP through electrospinning. The results of scanning electron microscopy (SEM) and atomic force microscopy (AFM) demonstrated that the addition of nanoparticles increased the diameter of PEP nanofibers from 148 nm to 163 nm, and the surface roughness of the fibers also increased. Meanwhile, the addition of nanoparticles improved the thermal stability of PEP nanofibers. PPP@CNPs/PEP nanofibers can inhibit the growth of E. coli O157:H7 on pork and cucumber surfaces during the five-days storage, and the inhibition rates were all above 95%. Besides, the nanofibers did not have any impact on the color and texture of foods.

Ginkgo biloba (Gb) is an ancient Chinese tree cultivated for its health-promoting properties. Moreover, Gb extract has a therapeutic effect, especially on neurodegenerative diseases. In this study, Gb extract-loaded chitosan nanoparticles (Gb-CsNPs) were synthesized by ionic gelation method. Size and zeta potential of the nanoparticles were analyzed and Scanning Electron Microscopy (SEM) and Fourier Transform Spectroscopy (FT-IR) were performed. Besides, encapsulation efficacy and loading capacity were calculated, and in vitro release, and cellular uptake studies were carried out. The biocompatibility of Gb-CsNPs was demonstrated and their neuroprotective activity was investigated on oxidative stress-induced SH-SY5Y cells. Apoptotic cells were monitored by DAPI, and cell migration was examined by in vitro scratch assay. Results showed that Gb-CsNPs had an average size of 104.4 nm, their zeta potential and polydispersity index (PDI) values were 29.3 mV, and 0.09 respectively. Encapsulation efficacy and loading capacity were found as 97.4% and 40%, respectively. It has been revealed that Gb-CsNPs were biocompatible and showed neuroprotective activity by increasing cell viability from 60% to 92.3%. Consequently, neuroprotective effect of the Gb extract was increased by chitosan encapsulation. This formulation is a candidate to be used as a food supplement after being supported by future in vivo studies.

This study revealed activation mechanisms of apatite by polyacrylamide (PAM) during flotation of rare earth minerals in Bayan Obo Ore. This activation leads to high phosphorus content in rare earth concentrate. Ultraviolet (UV) absorption measurements show that adsorption of PAM on the surfaces of apatite and rare earths follows a pseudo-second-order reaction kinetic model. The isothermal adsorption process follows the Freundlich adsorption model, indicating that the adsorption of PAM on apatite is a multi-layer, non-uniform process, that is, physical and chemical adsorption occurs simultaneously. The measured zeta potential shows that under weakly alkaline conditions, amide groups with a negative charge are adsorbed on the surface of apatite, increasing the electronegativity, so that the potential is shifted negatively; however, the negative shift of the potential on the surface of rare earths is insignificant. Fourier transform infrared (FT-IR) test and X-ray photoelectron spectroscopy (XPS) results imply that PAM is chemically adsorbed on the surface of apatite, while 506E undergoes stronger chemical adsorption than PAM on the surface of rare earth minerals. It is found that multi-layer, non-uniform adsorption of PAM combining physical and chemical adsorption occurs on the surface of apatite and the process is dominated by physical adsorption: the adsorption of PAM on surfaces of apatite is stronger than that on the surface of rare earth minerals. Such adsorption activates the apatite, causing it to float during the flotation of rare earths, which is the reason for the high phosphorus content in the rare earth concentrate.

The investigation of protein–nanoparticle interactions contributes to the understanding of nanoparticle bio-reactivity and creates a database of nanoparticles for use in nanomedicine, nanodiagnosis, and nanotherapy. In this study, hen's egg white was used as the protein source to study the interaction of proteins with sulphuric acid hydrolysed nanocellulose (CNC). Several techniques such as FTIR, zeta potential measurement, UV–vis spectroscopy, compressive strength, TGA, contact angle and FESEM provide valuable information in the protein–CNC interaction study. The presence of a broader peak in the 1600–1050 cm−1 range of CNC/egg white protein FTIR spectrum compared to the 1600–1050 cm−1 range of CNC sample indicated the binding of egg white protein to CNC surface. The contact angle with the glass surface decreased with the addition of CNC to egg white protein. The FESEM EDX spectra showed a higher amount of N and Na on the surface of CNC. It indicates the density of protein molecules higher around CNC. The zeta potential of CNC changed from −26.7 ± 0.46 to −21.7 ± 0.2 with the introduction of egg white protein due to the hydrogen bonding, polar bonds and electrostatic interaction between surface CNC and protein. The compressive strength of the egg white protein films increased from 0.064 ± 0.01 to 0.36 ± 0.02 MPa with increasing the CNC concentration from 0 to 4.73% (w/v). The thermal decomposition temperature of CNC/egg white protein decreased compared to egg white protein thermal decomposition temperature. According to UV–Vis spectroscopy, the far-UV light (207–222 nm) absorption peak slightly changed in the CNC/egg white protein spectrum compared to the egg white protein spectrum. Based on the results, the observations of protein nanoparticle interactions provide an additional understanding, besides the theoretical simulations from previous studies. Also, the results indicate to aim CNC for the application of nanomedicine and nanotherapy. A new insight given by us in this research assumes a reasonable solution to these crucial applications.

We incorporated oxidized dextran (Odex) into nanoparticles composed of gallic acid-modified chitosan (GA-CS) and sodium caseinate (NaCas). The mass ratio of GA-CS to NaCas and the pH of the reaction solution were optimized to obtain nanoparticles with excellent performance and stability. The interactions among various nanomaterials were confirmed by Fourier-transform infrared spectroscopy (FT-IR) and fluorescence spectrometer. The optimized complex nanoparticles had a diameter of approximately 131.2 nm with a polydispersity index (PDI) of 0.14, and a zeta potential of 26.2 mV. Our results showed that Odex enhanced the stability and function of GA-CS/NaCas nanoparticles (NP). At a curcumin loading of 10%, the encapsulation efficiency of Odex-crosslinked GA-CS/NaCas (NP (Odex)) was 96.2%, whereas that for uncrosslinked nanoparticles was 66.9%. Compared to the burst release profile of free curcumin in simulated GI fluids, the sustained release profile of encapsulated curcumin was observed. Radical-scavenging assays confirmed that the nanoparticles had excellent antioxidant activity themselves due to the grafting of phenolic acid on chitosan backbone. Overall, NP (Odex) with good GI stability and antioxidant activity hold promising for the oral delivery of hydrophobic bioactives.

Incorporation of silver nanowires in conductive adhesives leads to the reduction of resistivity due to the increased surface area and reduction of contact resistance. However, due to high surface energy, aggregation in the adhesive polymeric matrix leads to performance decline. In this research, in order to solve the aggregation issue and increase the contact surface area, silver nanowires functionalized with carboxylate groups and 21.6 μm and 130.5 nm lengths and diameters were synthesized via polyol technique with a −49.7 mV zeta potential at pH = 7 in aqueous media (energy barrier ≈ 20 K B T ). Also, functionalized nanowire suspension was stored in a mixture of solvents containing isopropyl alcohol, 1, 4-dioxane, and dimethyl sulfoxide maintaining stability for more than one year at the room temperature. Due to the good dispersion of the as-prepared silver nanowires in epoxy resin, increased adhesion density, reduction of air entrapment in the adhesive matrix during the curing process, and reduced oxidation rate, the as-prepared conductive adhesive with 50 wt% silver and 5 wt% polyethylene glycol showed a resistivity of 1.895 × 10-7 Ω cm.

Nanostructures of layered materials have gained increasing attention in photocatalytic and water-treatment processes. Herein, we report on sub-30 nm SnS2 nanosheets (NSs) which can perform photocatalytic reduction of Cr(VI) to Cr(III) quite efficiently on one hand, while removes large quantities of toxic organic dye molecules by choosing an adsorption mode of operation over photo-degradation on the other hand, unlike most other SnS2 nanostructures. The NSs have a highly extended crystallinity growing perpendicular to the (0 0 1) lattice direction but exhibit poor X-ray diffraction for the 10 l (1 = 1,2,3…) lattice planes. With such defects, the NSs have a narrow bandgap of 2.21 eV and exhibit a significant photocurrent density at near band-edge illumination. Cr(VI) photo-reduction using the SnS2 NSs follows a first-order reaction kinetics (rate constant of 0.10 min-1), five-fold higher than commercial TiO2 (P-25). Furthermore, the NSs adsorb Rhodamine B dye molecules from an aqueous solution by forming a monolayer of dye molecules following a pseudo-second-order kinetic model and exhibit an adsorption capacity of ∼ 53.28 mg/g. We show that the NSs have a Zeta potential of ∼ –22 eV and preferably adsorb cationic dyes only. Thus the SnS2 NSs can be effective for Cr(VI) contaminated waste-water treatment in a photocatalytic manner and can also act as a potential adsorbent for polluting dye molecules either in the presence or absence of sunlight. While both these activities are known for SnS2 as well as other materials, the competitive nature of the two mechanisms while each of them is a possibility has never been investigated. Therefore, besides the high activities, the study highlights the presence of different active sites on the material surface that can respond preferentially to either inorganic or organic impurities.

A porous hydrogel nanocomposite has been made by grafting poly(itaconic acid) on the polysaccharide, gum ghatti and by embedding magnetite nanoparticles in the copolymer gel matrix. This novel functional material Ggh-g-PIA/Fe3O4 was characterized by FTIR, TGA, SEM, EDS, XRD, BET, Zeta potential measurements and VSM techniques. The nanocomposite possesses mesoporous structure with high surface area and exhibits super-paramagnetic behavior due to the presence of magnetite nanoparticles. The hydrogel nanocomposite was evaluated as an adsorbent material for removal of dyes and divalent metal ions. Significant adsorption capacities of 410.2, 387.6, 416.5 and 401.4 mg g−1 towards methylene blue, rhodamine 6G, Cu (II) and Hg (II) ions respectively were observed. The adsorption isotherms were well described by the Freundlich isotherm model and kinetic studies demonstrated the adsorption to be a pseudo second order kinetic process. Intraparticle diffusion model suggested adsorption to occur by a multi-step diffusion process. Thermodynamic studies indicated a spontaneous and endothermic adsorption. Further, the desorption study indicated the possibility of successful regeneration of the adsorbent. A high removal efficiency, recyclability, convenient recovery after use due to the magnetic nature makes this polysaccharide based nanocomposite an environment friendly adsorbent material for water purification.

Enoxaparin is an effective biological molecule for prevention and treatment of coagulation disorders. However, it is poorly absorbed in the gastrointestinal tract. In this study, we developed an Eudragit® L100 coated chitosan core shell nanoparticles for enoxaparin oral delivery (Eud/CS/Enox NPs) through a completely eco-friendly method without employing any high-energy homogenizer technique and any organic solvents. Spherical nanocarriers were successfully prepared with particle size lower than 300 nm, polydispersity index about 0.12 and zeta potential higher than +25 mV, entrapment efficiency greater than 95% and the in vitro release behavior confirms the good colloidal stability and the successful Eudragit® L100 coating process demonstrated by negligible cumulative enoxaparin release (

Effective novel therapies are required for nasopharyngeal cancers since nasopharyngeal patients are dysfunctional, and treatment remains a significant challenge. Here, a co-loading core-shell structured lipid-polymeric hybrids nanoparticles with gefitinib (GEF) and apatinib (APT) was established (GEF-APT-LPHNs). The LPHNs size, polydispersive index (PDI), zeta potential, and drug release properties were effectively investigated. The in vitro proliferation assay and cellular uptake displayed superior activity against the CNE2 and SUNE1 cells. Further, the morphological features of the CNE2 and SUNE1 cells were established by the dual staining method and nuclear damage staining strategy. Additionally, we evaluated an in vitro assay to assess the hemolytic properties of nanoparticles and discuss with the experiment the observed nanointerference. To prevent misleading effects from nanoparticles, we are proposing alternate approaches, debating the possible importance of nanoparticles in vitro systems.

Carbon dots (CDs) are novel fluorescent nanomaterials with good water solubility, high resistance to photobleaching and low toxicity. While, there are few studies elaborate on the relationship among reaction conditions, properties and applications of CDs. In this study, a series of CDs are synthesized through a one-pot hydrothermal method, and different reaction conditions are carried out to study the influencing factors of CDs properties. As a result, with the increase of temperature and reaction time, the particle size and zeta potential of CDs increased, the maximum emission wavelength red-shifted and the fluorescence quantum yield (QY) improved. Among them, CD3006 has good water solubility and highest QY of 81.4%, which is beneficial for its applications in bioimaging and ion detection. CD3006 is almost nontoxic in cells at a concentration of 500 μg/mL. In addition, the positive charged CD3006 shows nuclear targeting potential because of its combination with DNA through electrostatic interaction in nucleus. The properties of CDs can be greatly enhanced by controlling reaction conditions, and it provides great application prospects.

Limited solubility and hepatic first-pass metabolism are the main causes of low bioavailability of anti-schizophrenic drug, Clozapine (CZP). The objective of the study was to develop and validate nanoemulsion (NE) based in-situ gel of CZP for intranasal administration as an approach for bioavailability enhancement. Solubility of CZP was initially investigated in different oils, surfactants and co-surfactants, then pseudoternary phase diagrams were constructed to select the optimized ratio of oil, surfactant and co-surfactant. Clear and transparent NE formulations were characterized in terms of droplet size, viscosity, solubilization capacity, transmission electron microscopy, in-vitro drug release and compatibility studies. Selected NEs were incorporated into different in-situ gel bases using combination of two thermosensitive polymers; Pluronic® F-127 (PF127) and F-68 (PF68). NE-based gels (NG) were investigated for gelation temperature, viscosity, gel strength, spreadability and stability. Moreover, selected NGs were evaluated for ex-vivo permeation, mucoadhesive strength and nasal ciliotoxicity. Peppermint oil, tween 80 and transcutol P were chosen for NE preparation owing to their maximum CZP solubilization. Clear NE points extrapolated from tween 80:transcutol P (1:1) phase diagram and passed dispersibility and stability tests, demonstrated globule size of 67.99 to 354.96 nm and zeta potential of -12.4 to -3.11 mV with enhanced in-vitro CZP release (more than 90% in some formulations). After incorporation of the selected N3 and N9 formulations of oil:Smix of 1:7 and 2:7, respectively to a mixture of PF127 and PF68 (20:2% w/w), the resultant NG formulations exhibited optimum gelation temperature and viscosity with enhanced CZP permeation and retention through sheep nasal mucosa. Ciliotoxicity examinations of the optimum NGs displayed no inflammation or damage of the lining epithelium and the underlying cells of the nasal mucosa. In conclusion, NE-based gels may be a promising dosage form of CZP for schizophrenia treatment.

Flotation separation of smithsonite from calcite is difficult due to their similar surface properties. In the present study, a reagent scheme of depressant calcium lignosulphonate (CLS) and collector benzyl hydroxamic acid (BHA) was introduced in the flotation of smithsonite from calcite. Microflotation tests revealed that the efficient flotation of smithsonite from calcite could only be obtained with the addition order of BHA before CLS, which was opposite to the widely-used order that adding depressant prior to the collector. The zeta potential measurements indicated that BHA selectively adsorbed onto smithsonite surface, then not allowed the CLS adsorption onto the smithsonite surface rather than calcite surface because of the steric hindrance, thereby the smithsonite surface remained hydrophobic while calcite surface became more hydrophilic after the addition of CLS. As a result, the calcite flotation was completely depressed while the smithsonite flotation recovery was still in high value, leading to the optimal flotation separation performance.

This study aimed to develop propolis and tea tree oil nanoemulsion loaded with clindamycin hydrochloride to heal wound effectively. Nanoemulsion formulae were prepared and characterized by droplet size analysis, zeta potential, viscosity, ex-vivo permeation, and skin deposition. The optimal formula was evaluated in terms of morphology, cytotoxicity, and in-vitro wound healing assay. Also, the efficacy of the optimal formula was evaluated by in-vivo wound healing and histopathological studies. The optimal formula (F3) was composed of 9% tea tree oil and 0.4% propolis extracts with mean droplet size 19.42± 1.7 nm, zeta potential value -24.5± 0.2 mV, and viscosity 69.4±1.8 mP. Furthermore, the optimal formula showed the highest skin deposition value 550.00±4.9 µg/cm2 compared to other formulae. The TEM micrograph of the optimal formula showed that the nanoemulsion droplet has an almost spherical shape. Also, the optimal formula did not show noticeable toxicity to the human skin fibroblast cells. The in-vitro and in-vivo wound healing assay showed unexpected results that the un-loaded drug nanoemulsion formula had a comparable wound healing efficacy to the drug-loaded nanoemulsion formula. These results were confirmed with histopathological studies. Our results showed that the propolis and tea tree oil nanoemulsion, whether loaded or unloaded with an antibiotic, is an efficient local therapy for wound healing.

The usefulness of sirolimus (SIR) in the treatment of diseases that involve retinal degeneration like age-related macular degeneration (AMD) has been well documented. However, the problem still remains probably owing to the peculiar environment of the eye and/or unfavourable physiochemical profile of SIR. In the present work, we aimed to fabricate sirolimus loaded PLGA nanoparticles (SIR-PLGA-NP) and chitosan decorated PLGA nanoparticles (SIR-CH-PLGA-NP) to be administered via non-invasive subconjunctival route. Both the nanoparticles were characterized in terms of size, zeta potential, DSC, FTIR and XRD analysis. Quality by Design (QbD) approach was employed during the preparation of nanoparticles and the presence of chitosan coating was confirmed through thermogravimetric analysis and contact angle studies. Cationic polymer modification showed sustained in-vitro SIR release and enhanced ex-vivo scleral permeation and penetration. Further, SIR-CH-PLGA-NP revealed enhanced cellular uptake and thus, reduced lipopolysaccharide (LPS)-induced free-radicals generation by RAW 264.7 cells. The prepared nanoparticles were devoid of residual solvent and were found to be safe in HET-CAM analysis, RBCs damage analysis and histopathology studies. Moreover, high anti-angiogenic potential was observed in SIR-CH-PLGA-NP compared with SIR-PLGA-NP in chorioallantoic membrane (CAM) test. Overall, the current work opens up an avenue for further investigation of CH-PLGA-NP as SIR nanocarrier in the treatment of AMD.

Harmful side effects of the chemotherapeutic agent have been investigated in many recent studies. Since Fe2O3 nanoparticles have proper porosity, they are capable for loading noticeable amount of drugs and controlled release. We developed Fe2O3/chitosan/montmorillonite nanocomposite. Quercetin (QC) nanoparticles, which have fewer side effects than chemical anti-tumor drugs, were encapsulated in the synthesized nanocarrier and were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), vibrating sample magnetometer (VSM), dynamic light scattering (DLS), and zeta potential. For quercetin, the encapsulation efficiency and the loading efficiency of the drug in Fe2O3-CS-MMT@QC were found to be about 94% and 57%, respectively. The release profile of QC in different mediums indicated pH-dependency and controlled release of the nanocomposite, adhering to The Weibull kinetic model. Biocompatibility of the Fe2O3/CS/MMT nanoparticles against the MCF-7 cells was shown by MTT assay and confirmed by flow cytometry. These data demonstrate that the designed Fe2O3-CS-MMT@QC would have potential drug delivery to treat cancer cells.

Flotation separation and recovery of rare earth minerals (REM) have returned to an important position due to the growing strategy demand for rare earth elements (REE). In this paper, a comparative investigation into the floatability of bastnaesite ((Ce,La)FCO3) was conducted by using three di/trialkyl phosphate collectors, di(2-ethylhexyl) phosphate (DEHPA), dibutyl phosphate (DBP) and tributyl phosphate (TBP). The density functional theory (DFT) computation recommends that the chemical activity of the three phosphate collectors is in order of DEHPA ≥ DBP >> TBP, and their hydrophobization as-suggested by the lgP (oil-water partition coefficient) value is in the order of DEHPA > TBP > DBP. The micro-flotation indicates that the preferable pH values for flotation of bastnaesite with the three phosphate collectors are 7.0–8.0, and DEHPA achieves much higher flotation recovery of bastnaesite, followed by DBP, and then TBP, which coincides with their reactivity and hydrophobicity, the two prerequisites for froth flotation. The contact angle, zeta potential, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) deduce that DEHPA likely reacts with the Ce(Ⅲ) atoms of bastnaesite interface through its O atom(s) of the P(=O)–O– group to generate the Ce–O–P bonds, and its two 2-ethylhexyl groups orient outside for attaching bubbles, resulting in flotation enrichment of bastnaesite. Furthermore, this investigation offers a novel strategy for developing collectors in selective beneficiation of REM.

As a kind of novel polyelectrolyte materials, poly(ionic liquids) (PILs) have excellent potentiality in the separation of ampholytes suchlike amino acids. Herein, the β-cyclodextrin-based PILs had been synthesized, followed by blending with poly(vinylidene fluoride) (PVDF) to prepare poly(ionic liquid) membranes (PILMs). The Fourier transformed infrared (FT-IR) spectroscopy, 1H nuclear magnetic resonance (1H NMR), scanning electron microscope (SEM), thermal gravimetric analysis (TGA), mechanical strength, zeta potential, and pore size distribution were characterized for these membranes or their intermediates. These PILMs had been developed for the selection separation of the amino acids mixture of L-glutamic acid (L-Glu) and L-threonine (L-Thr). The factors influencing the separation result were investigated, including the solution pH of the amino acids mixture and the PVDF amount in PILMs. The maximum selectivity of 55% can be obtain by one-step separation under the optimal conditions. This separation process using PILMs had the advantages of good selectivity, low operating pressure, larger water flux, and good reusability, which had the potentiality in the separation of various amino acids mixtures.

We developed a new hydrophobic polymer based on angico gum (AG), and we produced new nanoparticles to expand the applications of natural polysaccharides in nanomedicine. Phthalate angico gum (PAG) was characterized by 1H NMR, FTIR, elementary analysis, solubility, XRD, and TG. PAG was a hydrophobic and semi-crystalline material, a relevant characteristic for drug delivery system applications. As a proof of concept, nevirapine (NVP) was selected for nanoparticles development. Plackett-Burman's experimental design was used to understand the influence of several factors in nanoparticles production. PAG proved to be a versatile material for producing nanoparticles with different characteristics. Optimized nanoparticles were produced using desirability parameters. NVP-loaded PAG nanoparticles formulation showed 202.1 nm of particle size, 0.23 of PDI, -17.1 of zeta potential, 69.8 of encapsulation efficiency, and promoted modified drug release for 8 h. Here we show that PAG presents as a promising biopolymer for drug delivery systems.