Saline Medium Research Articles

Facile modification of polyvinylidene fluoride membrane for enhancing dialysis performance: sulfonation, adding polyethylene glycol and tuning coagulation bath temperature

Modifications were successfully carried out on the polyvinylidene fluoride (PVDF) flat sheet membrane, involving the sulfonation and adding polyethylene glycol (PEG), along with variations in the coagulation bath temperature (CBT). The primary objective of these modifications was to examine their impact on the physicochemical characteristics of the membrane and its permeability to a creatinine solution. The findings revealed that the sulfonated PVDF/PEG membrane, printed at a temperature of 30 °C, displayed substantial increases in porosity, hydrophilicity, water uptake and swelling degree. It is important to note that modifications to the PVDF membrane led to a reduction in thermal stability and an increase in creatinine transport efficiency. For the unmodified PVDF membranes, the clearance values for creatinine in phosphate buffer and phosphate buffer saline media were 0.43 (Transport = 28.65%) and 0.42 mg/dL (Transport = 28.05%), respectively. Conversely, the highest creatinine clearance values were achieved by the SPP30 membrane (sulfonated PVDF/PEG-CBT 30 °C), measuring 0.64 mg/dL (Transport = 42.81%) for creatinine and 0.60 mg/dL for urea (Transport = 39.66%). These results indicate that the sulfonated PVDF/PEG membrane exhibits strong potential for use in hemodialysis applications.

Effects of HepaSphere microsphere encapsule epirubicin with a new loading method transarterial chemoembolization: in vitro and in vivo experiments

MethodsHS microspheres were loaded in a solution of hypertonic saline and contrast medium at different ratios. Morphology, size distribution, and drug loading capacity of the microsphere were evaluated. Rabbits with hepatic VX2 tumors underwent conventional TACE, drug-eluting beads TACE with HS microsphere loading epirubicin by recommended method (dTACE) or a new loading method (ndTACE). The plasma and tissue epirubicin concentration, tumor necrosis, and the microsphere distribution within the tumor were assessed.ResultsIt was found that the mean diameter of HS microspheres was effectively reduced to 102 ± 14 μm after loading with 10.0% NaCl and Ultravist (370 mg I /mL) at a ratio of 2: 8 ml. The loading capacity reached 78.7%. It was noted that the concentration of tumor epirubicin was significantly higher (p = 0.016) in the ndTACE group (11,989.8 ± 5776.6 ng/g) than the concentration in the dTACE (6516.5 ± 3682.3 ng/g) and in cTACE groups (1564.1 ± 696.1 ng/g, p < 0.001). Further, the tumor necrosis in group with the new loading method (ndTACE) was 92.4%.ConclusionsThe size of HS microsphere can be effectively reduced when it is loaded with a mixture of hypertonic saline and non-ionic contrast material. HS microsphere loaded with epirubicin using the new method (ndTACE) can increase the drug concentration in tumor and hence exert better improved antitumor effect.

Synthesis of corundum rich coating on 7055 aluminum alloy by micro-arc oxidation and its corrosion resistant property in a saline medium

The work researched on Micro-arc oxidation (MAO) coatings fabrication method using 7055 aluminum alloy as substrate. The electrolyte was an alkaline solution added by sodium hexametaphosphate with/without sodium tungstate additive. X-ray diffraction (XRD) characterization proved that the α-Al2O3 (corundum)/γ-Al2O3 (gamma alumina) ratio in the coating reached 0.929 with trace tungsten metal, which was produced by thermit reaction. Scanning electron microscopy (SEM) characterization revealed craters up to 100 μm in diameter and micro-cracks on the coating surface. Energy dispersive X-ray spectroscopy (EDS) results indicated that the coating surface contains 0.74 at.% Mg, undetectable Zn and Cu, and 1.39 at.% Zr element, which should be 1.04 at.%, 1.51 at.%, 0.43 at.% and 0.02 % theoretically. Zr element distributed spatially in the same region with P element. The corrosion resistant property of the samples was analyzed by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization in 3.5 wt% NaCl. Tafel extrapolation method was utilized to analyze polarization curves and the results revealed that the corrosion potential of the MAO-treated sample was 0.016–0.093 V higher, and the corrosion current density was one order of magnitude lower (1/9.10–1/19.06) than the base 7055 aluminum alloy. The Nyquist diagrams of samples were modeled by equivalent electrical circuits through ZsimpWin software. The iterated data verified a three-layer structure of the MAO coating and the intermediate layer exhibited higher electrical resistance than the barrier layer. The coating film containing the most α-Al2O3 phase displayed the largest open porosity (3.99 % by calculation) and the highest electrical resistance. The friction test revealed that the coating fabricated under a higher current density possessed better wear resistance when the outer layer contacted the counterpair of Si3N4 ball.

Influence of UV exposure time and simulated marine environment on different microplastic degradation.

This study investigated the influence of environmental factors (UV radiation and salinity) in the degradative process of microplastics (MPs). MPs derived from polypropylene (PP), polystyrene (PS), and ethylene-vinyl acetate (EVA) were subjected to accelerated photodegradation while being submerged in distilled water or artificial seawater. Depending on the polymer, changes in surface properties, new functional chemical group formation and oxidative index, and thermal characteristics of samples were observed. After photodegradation experiments, EVA-MPs samples showed an increase in their thermal resistance, besides the changes in their surface. PP-MPs crystallinity index increased upon exposure to UV radiation. PS samples showed a higher carbonyl and hydroxyl index after 30h of UV exposure. The methodology exploited applies to any location in the world and can be comparable once considering the total ultraviolet index (UVI). The saline medium increases the crystallinity index of PP and EVA-MPs samples and intensifies the formation of new carbonyl and hydroxyl bonds in EVA-MPs samples. The results showed that several environmental factors should be considered in interpreting MPs photodegradation.

Release of cell-free enzymes by marine pelagic fungal strains.

Fungi are ubiquitous organisms that secrete different enzymes to cleave large molecules into smaller ones so that can then be assimilated. Recent studies suggest that fungi are also present in the oceanic water column harboring the enzymatic repertoire necessary to cleave carbohydrates and proteins. In marine prokaryotes, the cell-free fraction is an important contributor to the oceanic extracellular enzymatic activities (EEAs), but the release of cell-free enzymes by marine fungi remains unknown. Here, to study the cell-free enzymatic activities of marine fungi and the potential influence of salinity on them, five strains of marine fungi that belong to the most abundant pelagic phyla (Ascomycota and Basidiomycota), were grown under non-saline and saline conditions (0 g/L and 35 g/L, respectively). The biomass was separated from the medium by filtration (0.2 μm), and the filtrate was used to perform fluorogenic enzymatic assays with substrate analogues of carbohydrates, lipids, organic phosphorus, sulfur moieties, and proteins. Kinetic parameters such as maximum velocity (Vmax) and half-saturation constant (Km) were obtained. The species studied were able to release cell-free enzymes, and this represented up to 85.1% of the respective total EEA. However, this differed between species and enzymes, with some of the highest contributions being found in those with low total EEA, with some exceptions. This suggests that some of these contributions to the enzymatic pool might be minimal compared to those with higher total EEA. Generally, in the saline medium, the release of cell-free enzymes degrading carbohydrates was reduced compared to the non-saline medium, but those degrading lipids and sulfur moieties were increased. For the remaining substrates, there was not a clear influence of the salinity. Taken together, our results suggest that marine fungi are potential contributors to the oceanic dissolved (i.e., cell-free) enzymatic pool. Our results also suggest that, under salinity changes, a potential effect of global warming, the hydrolysis of organic matter by marine fungal cell-free enzymes might be affected and hence, their potential contribution to the oceanic biogeochemical cycles.

Mesoporous Layered Double Hydroxides: Synthesis for High Effective Uranium Ions Sorption from Seawater and Salt Solutions on Nanocomposite Functional Materials

A series of sorption materials based on layered double hydroxides (Co-Fe LDH, Ni-Fe LDH, and Zn-Ti LDH) were obtained by a facile and environmentally friendly method of coprecipitation. A low particle size of no more than 10 µm was achieved. The use of transition metals makes it possible to obtain compounds that are mechanically and chemically stable in aggressive environments. XRD analysis revealed that the compounds have a highly organized crystalline structure. Using SEM, it was determined that Co-Fe LDH and Ni-Fe LDH had a loose, highly dispersed surface structure, while Zn-Ti LDH had a monolithic surface structure. U(VI) adsorption on the obtained materials in solutions containing Na2CO3, Na2SO4, KNO3, NaCl, K3PO4, and NaHCO3, was studied in batch mode. The degree of purification in the presence of these salts reached 99.9%, while the distribution coefficient Kd reached 105 mL/g. Sorption capacity qmax and equilibrium adsorption constants Kf and KL for U(VI) adsorption in batch mode (for 24 h) from distilled and seawater were determined using the Freundlich and Langmuir equations. The highest sorption capacity of 101.6 mg/g in seawater and 114.1 mg/g in distilled water was registered for Co-Fe-LDH. The presence of competing ions in seawater can reduce sorption efficiency by up to 40%. The provided research allowed us to conclude that the obtained materials, Co-Fe LDH, Ni-Fe LDH, and Zn-Ti LDH are promising for the sorption removal of U(VI) from aqueous media of medium salinity.

Effects of salinity and UV-B on seed germination behaviour of the halophyte Zygophyllum album L.: Enforced dormancy and trade-off strategy

Understanding the behavior of halophyte seed germination under multiple abiotic stressors is crucial for restoring salt-affected lands. Zygophyllum album L. (syn. Tetraena alba (L.f.) Beier & Thulin) is a perennial halophytic species that spreads in the coastal ecosystems of Mediterranean areas. Halophytes' seed germination indices concerning the influence of UV-B remain unexplored in scientific investigations. We provide here data on the effects of salinity (0, 100, 200, and 400 mM NaCl) and light (total darkness, 12 h dark/12 h light, and 12 h dark + 9 h light + 3 h UV-B) on seed germination, seedling growth parameters, antioxidant enzymes, histochemical localization of O2−, and anatomical parameters of Z. album. The germination percentage was not significantly decreased under low and medium salinities (100 and 200 mM NaCl), but germination was entirely inhibited at 400 mM NaCl. Also, seed germination was reduced significantly under the combined treatment of 200 mM NaCl and UV-B light. The germination rate was significantly decreased at low salinity in darkness and under moderate salinity with all light treatments. However, the highest germination recovery was recorded under combined salinity and UV-B treatments. At the seedling stage, salinity reduced biomass and seedling length under all light treatments. Additionally, combined UV-B with salinity treatments had a negative synergistic influence on all growth parameters. On the other hand, the increase of catalase and peroxidase activities, as well as the accumulation of druses and idioblasts under combined treatment, suggest a trade-off between the growth of this species and its defense mechanisms. These results indicate that Z. album has a moderate tolerance to both salinity and UV-B stresses during germination, highlighting its significance as a potential source for reclaiming salt-affected lands and cultivating crops under future climate changes.

Biomimetic Inorganic Nanovectors as Tumor-Targeting Theranostic Platform against Triple-Negative Breast Cancer.

Mesoporous silicon nanoparticles (PSi NPs) are promising platforms of nanomedicine because of their good compatibility, high payload capacities of anticancer drugs, and easy chemical modification. Here, PSi surfaces were functionalized with bisphosphonates (BP) for radiolabeling, loaded with doxorubicin (DOX) for chemotherapy, and the NPs were coated with cancer cell membrane (CCm) for homotypic cancer targeting. To enhance the CCm coating, the NP surfaces were covered with polyethylene glycol prior to the CCm coating. The effects of the BP amount and pH conditions on the radiolabeling efficacy were studied. The maximum BP was (2.27 wt%) on the PSi surfaces, and higher radiochemical yields were obtained for 99mTc (97% ± 2%) and 68Ga (94.6% ± 0.2%) under optimized pH conditions (pH = 5). The biomimetic NPs exhibited a good radiochemical and colloidal stability in phosphate-buffered saline and cell medium. In vitro studies demonstrated that the biomimetic NPs exhibited an enhanced cellular uptake and increased delivery of DOX to cancer cells, resulting in better chemotherapy than free DOX or pure NPs. Altogether, these findings indicate the potential of the developed platform for cancer treatment and diagnosis.

Inhibitors using Aloe Vera to Reduce Corrosion of Carbon Steel HSLA X70 in saline media 3.5 M NaCl

The damage caused by corrosion in saline media affects carbon steel structures, so the use of inhibitors is a great alternative, however, industrial inhibitors have a high environmental impact. In search of sustainable alternatives, the present investigation investigated the inhibitory effect of aloe vera to reduce the corrosion of HSLA X70 steel by means of potentiodynamic polarization techniques and agar-agar gel, complementing microstructure characterization studies, the results show that 10%/V allows an efficiency of 82% to be able to protect X70 steel with great efficiency.

Soil Quality Improvement with Increasing Reclamation Years in the Yellow River Delta

The saline soils in the Yellow River Delta are primarily affected by seawater intrusion resulting from the intersection of land and sea, which exhibit variations in salinity. The quality of these soils is also influenced by anthropogenic reclamation, including fertilization and irrigation. This study quantitatively evaluated the distinct soil properties and soil quality characteristics of the Yellow River Delta during different reclamation years (i.e., 0a, 1a, 5a, 10a, and 20a) using principal component analysis (PCA) and the Soil Quality Index (SQI). The findings indicated that the soil salt content (SSC) significantly decreased (p &lt; 0.05) from 6.60 g/kg in the initial reclamation year (0a) to 1.63 g/kg in the 10th year (10a) and then slightly increased to 2.85 g/kg in the 20th year (20a). Consequently, the soil salinity level shifted from saline soil to slight salinity and then increased to medium salinity. Ammonium nitrogen (NH4+-N) notably increased by 8.31 mg/kg during the first five years of reclamation (0a to 5a) and gradually decreased by 2.56 mg/kg in the 20th year (20a). On the other hand, nitrate nitrogen (NO3−-N) experienced a significant decrease of 2–5 times after reclamation but continued to increase by 8.96 mg/kg with subsequent reclamation years. The available nitrogen (AN), available phosphorus (AP), and soil organic carbon (SOC) exhibited a significant increase of 24.87 mg/kg, 10.11 mg/kg, and 6.76 g/kg, respectively, with increasing reclamation years. However, available potassium (AK) gradually decreased after reclamation and then increased in the 20th year (20a). The values of SQI for different reclamation years were 0.307 for 0a, 0.339 for 1a, 0.320 for 5a, 0.318 for 10a, and 0.327 for 20a, indicating an increasing trend with increasing reclamation years. It was discovered that long-term reclamation significantly reduced soil salinity and improved soil quality, leading to the sustainable development of reclaimed saline soils in the Yellow River Delta.

Identification of Complex and Combined Antibody Consisted of Anti-c, Anti-E, Anti-Jka and Anti-Fya

To investigate the role of multiple serological methods in the identification of complex antibodies. The blood group antigens were detected by saline and microcolumn agglutination methods. The saline method was used to screen and identify IgM-type antibodies in the patient's serum, while the polybrene, anti-globulin, microcolumn agglutination, enzymic and absorption-elution methods were used to screen and identify IgG-type antibodies. The patient was B/CCDee/Jk(a-b+)/Fy(a-b+) blood type. The serum reacted with panel cells, and the reaction presented anti-E pattern in the saline medium. It was fully positive in the microcolumn agglutination card, except 2 negative ones after using papain to treat the panel cells. Referring to the pattern table, it was concluded that there existed anti-c, anti-E, and anti-Jka antibodies, and one antibody corresponding to an antigen that was easily destroyed by papain. The red blood cells with specific phenotype were selected for absorption-elution to identify IgG-type anti-c, anti-E, anti-Jka and anti-Fya antibodies. It is confirmed that IgM-type anti-E, and IgG-type anti-c, anti-E, anti-Jka and anti-Fya antibodies exist in the patient's serum by multiple serological methods.

Physiological fluid-assisted nanostructured NbN@Cu foam supercapacitor towards flexible and biocompatible energy storage applications

As the demand for implantable and wearable electronic devices is becoming prevalent, developing flexible and biocompatible energy storage is imperative. In this study, we have successfully fabricated a flexible and biocompatible supercapacitor. We used DC magnetron sputtering to deposit niobium nitride (NbN) on the copper foam (Cu foam) substrate to fabricate NbN@Cu foam. The fabricated NbN@Cu foam electrodes demonstrate a highly porous structure with uniform distribution of NbN on copper foam substrate. The in-vitro biocompatibility of the electrode was assessed using cell viability studies on the L929 fibroblast cells. The biocompatibility tests revealed no significant cytotoxic effects on the cell lines. The supercapacitor device demonstrated excellent electrochemical stability and efficient electrochemical performance (specific capacitance of 10.772 Fg−1 and 86.8 % retention after 5000 cycles). The device can operate in various physiological fluids (phosphate buffer saline and cell culture medium). These findings strongly suggest that the NbN@Cu foam supercapacitor holds significant promise as a flexible, and biocompatible energy storage device that can be used in a wide range of applications in wearable and implantable electronic devices.

Study of the Ecological and Reclamation Condition of Abandoned Saline Lands and Their Development for Sustainable Development Goals

To provide the population with food, it is very important to re-cultivate “abandoned lands” that have been retired from agricultural use. The conversion of arable land into agricultural abandoned lands in the south of Kazakhstan is, first of all, primarily associated with salinity. For the purposes of sustainable development, there is a need to develop proposals for re-mastering by studying their current state and reviewing world studies on the reclamation of salt-affected soils. Therefore, this study is devoted to the study of the current environmental and reclamation conditions of the abandoned areas of the Otyrar region in southern Kazakhstan. The proposed directions of changes in their development were also presented. In the course of the research, the historical method is used in the study of the emergence and formation of abandoned lands; the method of geographical analysis during the territorial analysis of the research object; the statistical and comparison methods in showing the complexity and intensity of the problems; the cartographic, geo-informational and field research (reconnaissance) methods in the study of the condition of the abandoned lands in the research object and methods of grouping and analysis were used in the work with scientific data on the topic of research. Using Sentinel-2 images, the GIS program created phenological dynamics of crops based on NDVI vegetation indices during the vegetation period of the irrigated range. By classifying them, abandoned lands due to salinization were separated from fields. By deciphering space images with the help of geoinformation technologies, it was revealed that the area of abandoned lands in the research object is 13,688.9 ha, including the area of non-saline soils—83.9 ha, weakly saline soils—984.4 ha, medium saline soils—2398.3 ha, and highly saline soils—10,222.1 ha. A review of the methods and technologies proposed by scientists for the development and amelioration of salt-affected lands was made. Taking into account the ecological and reclamation state of the object of research along with the material and technical capabilities of farms, two methods of developing abandoned lands (organic and agro-innovative) in the research object are proposed and the need for their use in case of soil salinization has been scientifically justified.

Adsorption and flocculation properties of a binary system based on (co)polymers of acrylamide and low- molecular weight amine-containing surfactants in a saline medium

The process of flocculation of a calcium-magnesium solid phase formed in an aqueous-salt solution with the introduction of calcium-containing precipitants using polyacrylamide, cationic and anionic acrylamide copolymers was studied. With the introduction of polymers, an increase in the dispersion settling rate was observed in the concentration range of 0.5–3.0 mg/g, to a greater extent for the anionic copolymer. In the presence of an amine-containing surfactant, the sedimentation rate increased with the introduction of polymers by a factor of 1.1–1.3 compared to dispersions without surfactants. Using an anionic copolymer as an example, it was shown that the adsorption of amine and the sedimentation rate of dispersion increase with the increase of the polymer molecular weight. It was found that the concentration of the anionic copolymer and the pH of the medium also influence the adsorption of amine. Based on the obtained data, an effective method of water-salt solutions purification from amine-containing surfactants and magnesium salts (purification degree 99.5–99.8 %) that can be used at mining and processing enterprises was developed.

Compatible Solutes Accumulated by &lt;i&gt;Glutamicibacter&lt;/i&gt; sp. Strain SMB32 in Response to Abiotic Environmental Factors

Abstract—Proton magnetic resonance spectroscopy was used for investigation of the pool of compatible solutes accumulated in the cells of Glutamicibacter sp. strain SMB32 in response to abiotic environmental factors. The original habitat of the strain was anthropogenically salinated soil at the Verkhnekamsk deposit of potassium and magnesium salts (Perm krai, Russia). The strain grew within the temperature range from 5 to 35°C. At 5 and 32°C, the intracellular content of trehalose in the cells of Glutamicibacter sp. SMB32 was significantly higher than at 25°C. Glutamicibacter sp. SMB32 was able to grow both in the absence of NaCl and at its concentrations up to 11%. Glutamate predominated in the cells growth without NaCl. At high salinity (8% NaCl), predominant compounds in the studied strain cells were trehalose, proline, glutamine, and glutamate. Increasing salinity of the growth medium resulted in higher levels of intracellular proline. This is the first report of ability of a Glutamicibacter strain to synthesize mannitol; its accumulation was found to depend on the aeration mode. Thus, Glutamicibacter sp. strain SMB32 possesses high metabolic plasticity and is able to adapt to the action of unfavorable physicochemical factors.

Experimental Modeling of Natural Processes of Nepheline Alteration

Nepheline, ideally Na3K(Al4Si4O16) is a key mineral of silica-undersaturated igneous rocks. Under subsolidus conditions, nepheline is intensively replaced by numerous secondary minerals, of which various zeolites (mainly natrolite, analcime, gonnardite), as well as cancrinite, muscovite and Al-O-H phases (gibbsite, böhmite, nordstrandite) are the most common. In the rocks of the Lovozero alkaline massif (Kola Peninsula, NW Russia), nepheline is extensively replaced by the association natrolite + nordstrandite ± böhmite ± paranatrolite. To reproduce the conditions for the formation of such a mineral association, a series of experiments were carried out on the dissolution of nepheline in deionized water, 0.5 mol/L NaCl, 0.5 mol/L NaOH, and 0.1 mol/L HCl at 230 °C for 1/5/15 days. When nepheline is partially dissolved, phases and mixtures of phases precipitate on the surface of its grains, and these phases were diagnosed using X-ray powder diffraction and Raman spectroscopy. Observations in natural samples and experimental studies have shown that the nepheline alteration in the rocks of the Lovozero massif with the formation of natrolite and Al-O-H phases occurred under the influence of a high to medium salinity solution at a pH of near 6.

Photometric Determination of Trace Amounts of Aluminum in Nearly Saturated Rock Salt Solutions Used by Chlor-alkali Industry

The previously widespread mercury cell technology in chlorine production has now been replaced by more environmentally friendly membrane cell electrolysis which is a Best Available Techniques (BAT) technology. However, this requires a much cleaner brine containing contaminants (Al, Ca, Mg, etc.) in the order of ng/g at most. For this reason, it’s very important to detect trace amounts of aluminum in concentrated saline media in the simplest and fastest way. To the best of our knowledge, no one has previously developed a spectrophotometric method capable of detecting aluminum in ionic forms selectively in the order of ng/g in concentrated saline media, without any preconcentration or separation step. Our advanced analytical method provides an opportunity for this. During the analytical procedure, a colored complex ion is formed from the dissolved aluminum content of the sample with eriochrome cyanine R (ECR) ligand in buffered pH medium. The sensitivity of the measurement is increased by adding quaternary ammonium salt. The colored complex ion is formed in 15 minutes, then the absorbance measurement can be performed for 90 minutes. The effect of rock salt interference was eliminated by proper calibration. In our work the dependence of the signal on temperature, pH, time elapsed after the addition of reactants, the dosing sequence, the salinity of the medium was examined, furthermore, we studied which wavelength-absorbance values give the best fit (highest R2 value) and the highest sensitivity in case of linear calibration. Surprisingly, increasing the salinity significantly improves the sensitivity of the measurement.

AkwaIbom (Iba Oku) Clay as Extender Pigment in Formulation of Anti-Corrosive Alkyd Paints for Saline Medium

AkwaIbom (Iba Oku) Clay as Extender Pigment in Formulation of Anti-Corrosive Alkyd Paints for Saline Medium

Enhanced electrochemical corrosion resistance of SS(304L) alloy with nano-pyramids c-TiN layer for saline media application

The present work evaluates the impact of the cubical titanium nitride (c-TiN) coating on the corrosion characteristics of the 304 L stainless steel SS(304 L). A thick and crystalline c-TiN layer with a hierarchical nano-pyramid-like structure was prepared by a single-step sputtered method at RT on a mechanically polished SS(304 L) substrate. Most of the basic characterization techniques were employed to understand the growth mechanism of c-TiN coating. The corrosion characteristics of the prepared coating were executed in two distinct ways, Tafel and EIS plots, in terms of polarization resistance (Rp) under saline water ambient [3.5 % NaCl]. The obtained results reveal the superior corrosion resistance of coated substrate compared to the bare substrate after a long immersion (∼6 h) of the sample in saline water. The c-TiN coated sample offers low corrosion current density (Icorr) (19.8 µA/cm2) compared to the bare substrate (213 µA/cm2). Similarly, EIS and equivalent circuit results also indicate superior corrosion resistance of c-TiN-coated SS-304 L, resulting in a significantly low corrosion rate (CR) of ∼ 0.0213 µmpy. The formation of corrosion products was discussed by using surface morphology analysis, while the electrochemical ion kinetic study was also presented to understand the anti-corrosion mechanism of c-TiN coating.

Chitosan Sponges for Efficient Accumulation and Controlled Release of C-Phycocyanin.

The paper proposed a new porous material for wound healing based on chitosan and C-phycocyanin (C-PC). In this work, C-PC was extracted from the cyanobacteria Arthrospira platensis biomass and purified through ammonium sulfate precipitation. The obtained C-PC with a purity index (PI) of 3.36 ± 0.24 was loaded into a chitosan sponge from aqueous solutions of various concentrations (250, 500, and 1000 mg/L). According to the FTIR study, chitosan did not form new bonds with C-PC, but acted as a carrier. The encapsulation efficiency value exceeded 90%, and the maximum loading capacity was 172.67 ± 0.47 mg/g. The release of C-PC from the polymer matrix into the saline medium was estimated, and it was found 50% of C-PC was released in the first hour and the maximum concentration was reached in 5-7 h after the sponge immersion. The PI of the released C-PC was 3.79 and 4.43 depending on the concentration of the initial solution.