Potassium Phosphate Research Articles

Effect of phosphate-to-magnesium ratio on the performance of magnesium potassium phosphate cement-based steel fireproof coatings

ABSTRACT The existing fireproof coating on thick steel structures has many drawbacks, including its lack of environmental protection, susceptibility to detachment, prolonged drying duration, and intricate building procedures. In this study, magnesium potassium phosphate cement (MKPC) was selected for the development of inorganic fireproofing coatings, considering that it has better adhesion, fast hardening speed, and heat resistance compared to other cement-based materials. P/M (the mass ratio of dipotassium hydrogen phosphate to magnesium oxide) is the most important factor affecting the performance of MKPC, which indicates the ratio of the acid and base components of the system. When P/M changed, so did the content of hydration products (MKP). The experimental results demonstrate a direct correlation between the quantity of MKP and the performance of the coating. Consequently, the bonding and fire resistance mechanisms of MKPC coatings were investigated by studying the effect patterns of different P/M on the properties (bond strength, fire resistance limit, dry density, compressive strength) of MKPC fireproofing coatings in combination with microscopic tests such as SEM, TG-DSC, and MIP.

Vibration of a mounted potassium dihydrogen phosphate crystal induced by the radiation pressure of a single-pass laser beam

Abstract We discovered that a mounted large-aperture potassium dihydrogen phosphate (KH2PO4, KDP) crystal vibrates elastically when it is irradiated by a single-pass high-average-power laser beam. A theoretical model is developed to study the vibration of the KDP crystal caused by the radiation pressure of the laser beam, treating the radiation pressure caused by reflection as a static force. Additionally, the deformation and surface shape of the vibrating KDP crystal are calculated. It shows that a mounted 40 cm-level-aperture KDP crystal elastically vibrates at the pico-meter scale when irradiated by a single-pass laser beam at the GW/cm2 level.

Chemical Conjugation of Iron Oxide Nanoparticles for the Development of Magnetically Directable Silk Particles.

Magnetically directable materials containing iron oxide nanoparticles (IONPs) have been utilized for a variety of medical applications, including localized drug delivery. Regenerated silk fibroin (RSF) has also been used in numerous regenerative medicine and drug delivery applications, given its biocompatibility and tunable properties. In this work, we explored the hypothesis that chemically conjugating IONPs to RSF to anchor the IONPs to silk microparticles would provide better magnetic guidance than nonconjugated IONPs untethered to silk microparticles. IONPs were fabricated using a coprecipitation method and conjugated with glutathione (GSH) prior to mixing with RSF. IONPs incorporated into RSF were mixed with potassium phosphate buffer to fabricate microparticles. IONPs with and without GSH were characterized for particle size, shape, morphology, GSH conjugation efficiency, and composition. Silk iron microparticles (SIMPs) were also characterized for particle size, shape, and composition and tested for stability, degradation properties, magnetic movability, and cytotoxicity. IONPs demonstrated a uniform size distribution and spherical morphology. Conjugation of IONPs with GSH was verified through changes in the X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) spectra. IONPs and RSF were able to be chemically conjugated and fabricated into SIMPs, which demonstrated a spherical and porous morphology. FTIR revealed an increased β-sheet content in SIMPs, suggesting that the IONPs may be inducing conformational changes in the silk fibroin. SIMPs showed stability up to 4 weeks in ultrapure water and rapid enzymatic degradation within 24 h. SIMPs were able to be moved magnetically through solution and through a hydrogel and were not cytotoxic.

Separation of heavy metals using aqueous two-phase systems based on choline chloride/urea and betaine/urea deep eutectic solvents

The heavy metals in the effluents of industries threatens the human health. In this research, aqueous two-phase systems based on two deep eutectic solvents, choline chloride/urea and betaine/urea, along with dipotassium hydrogen phosphate, were used as environmentally friendly systems to extract hexavalent chromium. Binodal curves and tie lines were obtained for two systems. The effect of temperature, pH, metal concentration and salt composition was investigated on the extraction efficiency of chromium. Increasing the temperature, the concentration of metal and the amount of salt increased the extraction efficiency. The system consisting of choline chloride/urea had better extraction than other and showed extraction efficiency of 86.82 ± 1.99 at pH = 10 and temperature of 25 ºC and metal concentration of 80 mg/l. the system based on betaine/urea showed extraction efficiency of 89.51 ± 1.69 at pH = 8.9 and temperature of 25 °C and metal concentration of 80 mg/l. Considering the same cost of two systems, the system including betaine/urea was evaluated as a better system for the separation of chromium. These systems were also used to separate lead, cobalt, nickel and cadmium that showed their high tendency to the low phase.

The influence of different operational variables on the production of crystalline monopotassium phosphate

The influence of different operational variables on the production of crystalline monopotassium phosphate

Application of Plant Growth Regulators During Early Fruit Development Stage Increased Perceived Sweetness of Mango Fruit

This study investigated the optimal strategies for improving sugar biosynthesis in mango fruits. Randomized block design was used for experimental treatments. The mango cultivar “Renong-1” was sprayed with five green plant growth regulators, including solutions of SBP (sucrose-based polymers, a new highly efficient and eco-friendly plant growth regulator), SPM (sucrose + potassium dihydrogen phosphate + microelement fertilizer), TPM (taurine + potassium dihydrogen phosphate + microelement fertilize), PFA (potassium fulvic acid), and SOP (seaweed oligosaccharide peptide) at different fruit development stages. Indicators, such as soluble solid content, soluble sugar and starch contents, and activities of 11 enzymes associated with sugar metabolism in physiologically mature and in full ripening fruits were evaluated. The results showed that SBP solution diluted 100-fold exerted the strongest effect on the soluble sugar content and sweetness value of “Renong-1” mango fruits. Based on the linear regression analysis, a significant negative correlation was observed between the activity of acid invertase and the perceived sweetness of physiologically mature fruits, while the activities of other enzymes were significantly negatively correlated with the perceived sweetness of full ripening fruits. According to multiple regression (by lars function in R) and other comprehensive analysis, A1B3 (spraying SBP solution one time in the young fruit stage) was selected as the optimal treatment combination for enhancing “Renong-1” mango perceived sweetness, followed by A1B2 (spraying SBP solution for the first time in the young fruit stage and the second time at medium maturity) as the alternative treatment combination.

Optimization of Culture Medium Ingredients and Culture Conditions for Bacteriocin Production in Lactococcus lactis NCU036019.

Bacteriocin lactococcin036019 was identified and characterized from Lactococcus lactis NCU036019, which displayed significant antibacterial activity toward foodborne pathogenic bacteria Staphylococcus aureus under various conditions. However, the in situ low-level expression of lactococcin036019 severely limited its wide application in food industry. In this study, we optimized the medium ingredients and culture conditions of L. lactis NCU036019 for maximum production of lactococcin036019. The effects of different carbon sources, nitrogen sources, inorganic salts, growth factors, surfactants, and buffer salts on the production of bacteriocin were studied using antibacterial titer and diameter of inhibitory zone as evaluation indexes. Through single-factor experiments, Plackett-Burman (PB) experiment, steepest ascent experiment and response surface methodology, yeast extract, zinc sulfate, sodium acetate, mannitol, Tween-80, and dipotassium hydrogen phosphate were identified to display significant influence on the production of bacteriocin. By optimizing Man Rogosa and Sharpe (MRS) culture medium ingredients, the antibacterial activity of lactococcin036019 in the cell-free supernatant raised from 46.19 to 300.14Au/mL, namely, 6.5 times increased. Furthermore, the culture conditions, such as inoculation amount, culture time, and culture temperature, were optimized, and this further increased the antibacterial activity to 409Au/mL, namely, 8.8 times increased. This study investigated the effects of culture media and conditions on the production of lactococcin036019, and they were optimized for a maximum harvest of bacteriocin, and the significant increase of bacteriocin production in L. lactis NCU036019 facilitates the application of the antibacterial substance in future work.

Sustainability assessment of the micellar optimized HPLC method for concomitant quantification of a common triple regimen for cardiovascular disorders: application to marketed formulations and in vitro dissolution testing.

Hypertension and dyslipidemia are two of the most frequently co-occurring cardiovascular risk factors. The combined regimen of hydrochlorothiazide (HCTZ), rosuvastatin (ROS), and losartan (LOS) helped in the successful management of both conditions. This work's objective is to develop an eco-friendly, sensitive, simple, and reliable chromatographic method for the simultaneous estimation of HCTZ, ROS, and the LOS ternary mixture in their pure form, and pharmaceutical formulations. Utilizing sodium dodecyl sulphate (SDS) in combination with polyoxyethylene-23-lauryl ether (Brij-35) could be a greener option with minimal environmental impact in liquid chromatographic separation techniques. Therefore, a micellar HPLC protocol was optimized and validated employing a mobile phase comprising a mixture of micelles of SDS (0.15 mol L-1) and Brij-35 (0.03 mol L-1) with 0.01 M monobasic potassium phosphate buffer, pH 3.5. The cited drugs were detected at 230 nm within five minutes, using a symmetry RP-C18 column, an isocratic elution mode, and a flow speed of 1 mL min-1. Method validation was successfully performed as stated by ICH. The suggested HPLC approach was effectively applied to determine the mentioned drugs in three pharmaceutical preparations. It was also employed for monitoring their in vitro release pattern using two innovator tablet formulations, applying the USFDA guidelines. The applied procedure was evaluated and compared with previously published HPLC approaches using various metrics, including the Eco-Scale Scoring method (AES), the Green Analytical Procedure Index (GAPI), and the Analytical Greenness Calculator (AGREE) for greenness, the most current Blue Applicability Grade Index (BAGI) for blueness, and the more inclusive RGB 12 algorism for whiteness assessment.

Stability indicating RP-HPLC technique for simultaneous estimation of nirmatrelvir and ritonavir in their new copackaged dosage form for COVID-19 treatment

RP-HPLC technique was developed and optimized for simultaneous identification and estimation of nirmatrelvir (NIR) and ritonavir (RIT) in their new copackaged tablet. Stability of nirmatrelvir (NIR) was studied after exposure to different five stress conditions; alkali, acid, heat, photo and oxidation degradation. The chromatographic separation was achieved using VDSpher PUR 100 ODS (4.6-mm x 15-mm), 3.5 μm column and mixture of 0.03 M potassium di-hydrogen phosphate buffer pH 4 and acetonitrile (45:55, v/v) as mobile phase. The column temperature was set at 40 °C, flow rate at 1mL/min and UV detection at 215 nm. The NIR and RIT retention times were 3.94 ± 0.08 min and 9.08 ± 0.1 min, respectively. Linear relationship was established in range of (1.5–105 µg/mL) for NIR and (1–70 µg/mL) for RIT with good reproducibility. The found mean percentage recoveries of nirmatrelvir (NIR) and ritonavir (RIT) were 100.03% and 99.85%, respectively. The developed method shows very good sensitivity as the LOQ and LOD were found to be 3.001 & 0.990 µg/mL, respectively for NIR and 2.765 & 0.912 µg/mL, respectively for RIT. The developed approach was validated concerning to ICH guidelines and applied successfully for the simultaneous estimation of NIR and RIT in their new copackaged dosage from. The results of assay using the proposed approach were compared statistically to the results found by applying the published one with good agreement.

Integrated Carbon Layer and CoNiP Cocatalyst on SnWO4 Film for Enhanced Photoelectrochemical Water Splitting.

α-SnWO4 is a promising semiconductor for solar water splitting, however, its performance is limited by weak water oxidation and poor charge transfer. In this study, we employ a vapor deposition method to uniformly implement a carbon layer onto the surface of SnWO4 coupled with a CoNiP cocatalyst, successfully constructing the integrated CoNiP/C/SnWO4 film photoanode and alleviating the oxidation of Sn2+ when loading electrocatalyst. Incorporating the carbon layer enhances the interface charge conduction behavior between the SnWO4 substrate and the CoNiP cocatalyst, thereby mitigating charge recombination. The synergistic interplay between the carbon layer and CoNiP leads to a remarkable achievement, as evidenced by the photocurrent of 1.72 mA cm-2 (1.23 V vs. RHE) observed for SnWO4 film measured in 0.2 M potassium phosphate buffer solution. In this work, we demonstrate the viability of tailoring SnWO4 photoanode and provide valuable insights for prospective advancements in modifying SnWO4 photoanode.

Research on detection methods of related substances and degradation products of the antitumor drug selpercatinib.

Selpercatinib, a selective RET kinase inhibitor, is approved for treating various cancers with RET gene mutations such as RET-rearranged thyroid cancer and non-small cell lung cancer. The presence of process-related and degradation impurities in its active pharmaceutical ingredient (API) can significantly affect its safety and effectiveness. However, research on detecting these impurities is limited. This study developed and systematically validated a High-Performance Liquid Chromatography (HPLC) method for identifying selpercatinib and its related impurities. The method utilized a 4.6mm × 250mm chromatographic column with 5μm particles, employing a flow rate of 1.0mL/min, a detection wavelength of 235nm, an injection volume of 10μL, and a column temperature of 35°C. Mobile phase A was composed of a 9:1 ratio of water to acetonitrile, with the aqueous component adjusted to pH 2.5 and containing 2mM potassium dihydrogen phosphate (KH2PO4) and 0.4% triethylamine. Mobile phase B was pure acetonitrile. The gradient elution program was as follows: 0-2min, 5%B; 2-15min, 5% to 15%B; 15-30min, 15% to 35%B; 30-35min, 35% to 45%B; 35-36min, 45% to 5%B; 36-45min, 5%B. The chromatographic method established in this study was validated according to the ICH Q2 (R1) guidelines. The developed HPLC method demonstrated excellent specificity, sensitivity, stability, linearity, precision, accuracy, and robustness. It efficiently separated the impurities present in selpercatinib, thereby confirming the method's efficacy in ensuring the purity and quality of the drug. The chromatographic method established in this study can be used for the detection of selpercatinib and its impurities, providing significant reference value for the quality research of selpercatinib bulk drug and its preparations, and ensuring the safety of medication for patients.

New easy lab methods for the extraction of phycobiliproteins and pigments from cyanobacteria

Abstract Cyanobacteria are a source of a variety of valuable substances. These include extracellular polymeric substances (EPS) and natural dyes. EPS are produced by cyanobacteria to protect themselves against environmental stresses, serve as a water reservoir, and play an essential role in the formation of biofilms. They can be used, for example, due to their antimicrobial properties. Cyanobacteria are phototrophic organisms and synthesize the pigments chlorophyll a and carotenoids for photosynthesis. However, they also possess other light-harvesting complexes in the form of phycobilisomes, which combine with proteins to form so-called phycobiliproteins (PBP). These enable cyanobacteria to utilize a larger light spectrum than plants. Both the pigments and the PBP can be used as natural colorants and offer antioxidant properties, among other things, which enables applications in medicine. Methods for the combined extraction of EPS, PBP, and pigments have already been described in the literature. Still, in this work, the methods were simplified and optimized to obtain the best possible method for use in the laboratory. The optimized downstream process is based on an extraction of the EPS with deionized water followed by an extraction of the PBP with potassium phosphate buffer and finally the extraction of the pigments with methanol. The PBP and pigments are extracted by adding fixed ratios of solvents followed by a single extraction for a certain period. The universal applicability was demonstrated over a broad biomass spectrum from 4 mg to 80 mg dry mass and the method was transferred to several cyanobacterial strains.

Formation of a Novel Antagonistic Bacterial Combination to Enhance Biocontrol for Cucumber Fusarium Wilt.

Paenibacillus polymyxa strain PJH16, isolated and tested by our team, suppresses cucumber Fusarium wilt as an efficient biocontrol agent. For further investigation, the strain has been combined with two other Bacillus strains (Bacillus velezensis VJH504 and Bacillus subtilis JNF2) to enhance biocontrol ability, which formed high-efficiency microbial agents in the current study. The methodological target taken is based on achieving the optimal growth conditions of the combined microbial agents; hence, the medium composition and culture conditions were optimized through a single-factor test, orthogonal test and response surface methodology. Following this, the effectiveness of the microbial combination was assessed through pot experiments, which provided a theoretical foundation for the synthesis of microbial flora to significantly control cucumber Fusarium wilt. The results showed excellent compatibility, proving suitable for the proliferation and growth of Paenibacillus polymyxa PJH16, Bacillus velezensis VJH504, and Bacillus subtilis JNF2 strains together, specifically, when the inoculation amounts were adjusted to 4% of each. Using the single-factor test and orthogonal test analysis, the optimum composition of culture medium for the composite strain was identified as 3% glucose as the optimal carbon source, 2% yeast extract powder as the preferred nitrogen source, and 1% dipotassium hydrogen phosphate as the most suitable inorganic salt. Furthermore, the optical density (OD600) of the composite strain solution reached its highest level at 3.16 under the following culture conditions: inoculation volume of 200 µL, 171 rpm culture speed, 21.6 h culture time, 30 °C cultural temperature, and an initial pH of 7.0. The pot experiment demonstrated that the mixed bacterial solution achieved a relative control efficacy of 93.4% against cucumber Fusarium wilt, which was significantly superior to that of single- strain or pesticide treatment, and also promoted cucumber growth. In summary, the microbial flora synthesized by the three Bacillus strains displayed a high bacterial concentration, following the optimization of culture conditions, and exerted remarkable control and growth-promoting effects on cucumber Fusarium wilt. This finding holds great significance for future developments of composite microbial agents.

Activation of BOF Slag with Dipotassium Hydrogen Phosphate: Enhancing Hydration, Carbonation Resistance, and Heavy Metal Leaching

Activation of BOF Slag with Dipotassium Hydrogen Phosphate: Enhancing Hydration, Carbonation Resistance, and Heavy Metal Leaching

Unapproved potassium phosphate products increase risk of aluminum toxicity in infants.

Unapproved potassium phosphate products increase risk of aluminum toxicity in infants.

Effect of wollastonite content on rheology and mechanical properties of 3D printed magnesium potassium phosphate cement-based material of MgO-SiO2-K2HPO4

Effect of wollastonite content on rheology and mechanical properties of 3D printed magnesium potassium phosphate cement-based material of MgO-SiO2-K2HPO4

Stabilization of Zinc Ions and Potassium Phosphates Using Milk Protein Hydrolysates and In-Vitro Evaluation of Dentinal Tubule Occlusion

Stabilization of Zinc Ions and Potassium Phosphates Using Milk Protein Hydrolysates and In-Vitro Evaluation of Dentinal Tubule Occlusion

Advancing damage‐free machining of KDP: A comprehensive review

AbstractThe series of successful inertial confinement fusion ignitions from December 2022 to December 2023 marked a groundbreaking milestone in humanity's pursuit for a new, inexhaustible source of clean energy. At the core of this ignition system lies the potassium dihydrogen phosphate (KDP) crystals, playing an indispensable role. However, ensuring the reliable, long‐term application of KDP components relies heavily on their quality, necessitating finishes that are free from damage or nearly so. Manufacturing KDP components poses significant challenges due to their fragility, unstable microstructure, sensitivity to environmental factors and complex mechanical behavior. To address the quest for damage‐free manufacturing, interdisciplinary investigations have been commenced, incorporating theoretical analyses, atomistic simulations, and experimental trials. The success of the ignitions has catalyzed intensified research efforts aimed at achieving damage‐free machining of KDP components, drawing significant attention. This review is dedicated to examining existing studies on machining‐induced damage mechanisms and exploring potential pathways for achieving damage‐free machining of KDP crystals.

Role Assessment of Water-Soluble Pharmaceutical Form of Phosphatidylcholine on the Catalytic Activity of Cytochrome P450 2C9 and 2D6.

This study aimed to investigate whether the water-soluble pharmaceutical form of phosphatidylcholine nanoparticles (wPC) stimulated the catalytic activity of CYP enzymes 2C9 and 2D6. We have shown that electroenzymatic CYP2C9 catalysis to nonsteroidal anti-inflammatory drug naproxen as a substrate was enhanced from 100% to 155% in the presence of wPC in media. Electroenzymatic CYP2D6 activity in the presence of the adrenoceptor-blocking agent bisoprolol as a substrate was elevated significantly from 100% to 144% when wPC was added to potassium phosphate buffer solution. These results indicate the ability of wPC in the form of the phospholipid ultra-small nanoparticles to work as a membrane additive and crowding agent to accelerate the electroenzymatic reactions of cytochrome P450.

Optical method for dissolution/diffusion process multiparameters simultaneous measurement based on liquid-core cylindrical lenses.

The dissolution/diffusion process of solid in a liquid is a kind of widespread physical phenomenon. Parameters involved in this process include the dissolution rate (dC/dt), dissolution rate constant (K), and diffusion coefficient (D), whose accurate measurement is particularly important in fields such as biopharmaceuticals, materials science, agriculture, etc. However, the commonly used measurement methods at present cannot obtain these parameters simultaneously. Besides that, the measurement process is always not intuitive and time-consuming. This study introduces a method for measuring the multiple parameters of potassium dihydrogen phosphate (KDP) dissolving and diffusing in water under three states (powder, solid, and crystal) based on a compound liquid-core cylindrical lens (SLCL-Doublet) using a real-time optical image feature extraction method. Based on the relationship between the dissolution/diffusion image width and the solution concentration, dynamic spatiotemporal distribution of the solution concentration can be established, which can be used to calculate the D values based on Fick's second law, and the dC/dt, K values based on Noyes-Whitney equation, accordingly. At last, the area of solid-liquid contact surfaces is determined based on the relationship between K and D in the Nernst-Brunner equation, confirming the accuracy of the measurement data from the side. The optical method for simultaneously measuring the multiple parameters in the dissolution/diffusion process introduced in this study can be widely used to quickly expand the basic data required for chemical and pharmaceutical industries.