Optimum pH Range Research Articles

Enhanced Heavy Metal Removal from Wastewater Produced by Chemical Analysis Laboratory Using Calcium Oxide Precipitation: pH Improvement and Characterization of Precipitated Phases

This article presents research results on the precipitation of heavy metals: Aluminum (Al), arsenic (As), cadmium (Cd), zinc (Zn), iron (Fe), chromium (Cr), copper (Cu), nickel (Ni), vanadium (V), and molybdenum (Mo) from wastewater generated in mining chemical analysis laboratory. Calcium oxide was used as the precipitating agent. The efficiency of heavy metal removal was achieved by increasing the dosage of precipitating reagent (8-28 g/L). Efficiencies greater than 90% are achieved. The efficiency of chemical precipitation depends on the pH of the process. Over a wide pH range from 6-11, the removal efficiency of zinc, iron, cadmium, and arsenic were approximately 99.9%. The optimum pH range for the removal of most elements was found to be between 8 and 11, where the removal efficiency of heavy metal ions reached up to 99%. Furthermore, X-ray diffraction results indicated that the metals in the wastewater precipitated in various forms as mentioned in Table 7, and not just as hydroxides, due to the presence of different ions in the solution.

Lanthanum Cerate Microspheres for Efficient Fluoride Removal from Wastewater.

The performance of lanthanum cerate microspheres (LCM) at removing fluoride was analyzed in batch experiments after they were synthesized via the hydrothermal strategy. The ball-shaped microsphere morphology of LCM is confirmed by SEM and TEM. The synthesized LCM adsorbent showed excellent adsorption capacity in the pH range 3.0-7.0, with the optimal pH range being 3.5-4.5. The Langmuir adsorption model was more appropriate than the Freundlich model for describing the adsorption isotherm. The LCM adsorbent exhibited a significantly higher Langmuir adsorption capacity of 104.83 mg/g at pH 4.0, surpassing that of any other reported adsorbent. We investigated the adsorption of fluoride under a variety of conditions, including the presence of distinct anions. Furthermore, testing the adsorbent in actual groundwater demonstrated its high effectiveness in removing fluoride. Different useful analytical techniques were used for measurements and to learn and deduce the adsorption mechanism.

A robust method for the determination of lead in water samples using flow injection hydride generation atomic absorption spectrometry

Flow injection hydride generation atomic absorption spectrometry (FI-HGAAS) is a sensitive technique for the quantification of trace amounts of lead. However, plumbane generation is not straightforward and usually HG methods for lead are not robust enough for routine analysis. The optimum pH range for Pb HG is very narrow, so strict control of the acidity of the reaction medium is required for reliable results and in some cases even acid concentrations used for sample preservation can interfere. Moreover, some elements, like Cu, can interfere in the HG reaction suppressing the Pb signal. In this paper we report the development and validation of a method for the determination of Pb in water samples that is robust towards acidity and Cu levels usually found in water samples.All hydride generation parameters were optimized, but special emphasis was put on robustness. The use of borate as a buffer significantly improved the robustness of the method towards acidity, compared to the typical non-buffered HG. Furthermore, the interference of Cu, Sb and Sn in the HG reaction was overcome using thiocyanate as a masking agent. Other elements do not interfere at levels typically found in water samples. The limit of quantification achieved (0.9 μg L−1) is below the current guideline value for Pb in drinking water (10 μg L−1). The linearity of the method was verified between the LOQ and up to 15 μg L−1. An analytical frequency of 25 samples per hour with 3 measurement replicates each was achieved. The method was applied to the analysis of 50 water samples. The concentrations found ranged from <LOD (0.3 μg L−1) and up to 88.8 μg L−1.The proposed method is robust, cost-effective, easily automated and does not require unconventional or expensive equipment. It can be applied for routine analysis of different types of water samples.

Formulation, Analytical Method Development and Validation of an Emulsion of Multi-enzyme with Carminative Oils

Introduction:: Indigestion leading to Flatulence is a common problem for infants, and tackling it is tedious for the parents. So, addressing the issue with an ideal formulation should likely have a combination of digestive enzymes and carminatives. Methods: A formulation containing enzymes like Fungal Diastase (Amylase) and Papain (Protease) for the digestion of Carbohydrates and Protein, respectively, along with aromatic, volatile, carminative oils like Dill Oil, Anise Oil, and Caraway Oil can serve the purpose to mitigate problems associated with infant indigestion and flatulence with maximum compliance. Results: The stability of multi-enzyme and analysis of carminative oil mixtures still need to be improved due to their inherent characteristics. Enzymes are very likely susceptible to changes in temperature and pH, while the solubility of carminative oils is minimal in the aqueous phase. Also, each enzyme is stable in different pH ranges. Nine emulsions were developed using a suitable buffer system and analyzed by HPLC method. Conclusion:: The optimum pH range was found, and analytical method validation was done for the method's accuracy, precision, and repeatability. The optimum pH was 6-6.5, and the active pharmaceutical ingredients (API) assay was found within the acceptable limit of NLT, 90% for enzymes and 90-110% for carminative oils.

Production and Applications of Keratinases in Industry

Keratin is an insoluble protein with fibrous structure. It is mainly found in hair,feathers,nail,wool and horn of various animals. These animal accessories can be utilized as animals feed, amino-acids and fertilizers. This insoluble protein is very difficult to degrade and has extreme stability because it has disulfide bonds, hydrogen and hydrophobic interaction present in it. But keratin can be easily digested by keratinase enzyme. Keratinase is an extracellular enzyme. It also degrades keratin in prokaryotic organisms. Microorganisms that produce keratinase are species of Bacillus, Actinobacteria and fungi. It can also be obtained from Streptomyces, Aspergillus, Fervidobacterium, Xanthomonas, Chryseobacteriumand Vibrio. Keratinases produced by microbes arevery diverse due to their chemical as well as physical properties. It is a vigorous enzyme that can survive broad pH and temperature. Their optimum pH range is neutral to alkaline and their optimum temperature reported is 40°C to 60°C. And thermophiles have also been reported for stable microbial activity. Microbial keratinases are cheaply available as compared to conventional producers for keratinases production. They have gained great significance in biotechnology by acting on strong, inflexible cross linked polypeptide structure of keratin instead of ordinary proteolytic enzyme papain, trypsin or pepsin. They are mostly extracted by degrading keratin as substrate. Keratin substrates include feather, hair, wool,horn and nails. This degradation process is helpful in converting keratinous wastes in to fertilizer and poultry feed. Other renowned biotechnological implementations include removing hair from leather by using keratinase, development of bio-polymer from keratinous fiber, delivering drug, hydrolysis of prion proteins and detergent industry. They are also used in converting biomass in to biofuel that significantly boosts power preservation and recycling. The main problem for producing enzymes on large scale is their costly production procedures. This hurdle is overcome by utilizing keratin waste eg feathers of chicken as fermentation substrate on industrial scale. The benefit of utilizing this left over is extremely cost effective fermentation process of keratinase and the effluents are environmental friendly. Keratinase enzyme has become popular and provided newly effective and efficient way for managing waste products by using them on industrial scales as substrates which gives rise to environmental friendly industries for nonstop development.

Industrial-scale anaerobic Co-digestion (ACoD) of palm oil mill effluent (POME) and decanter cake (DC) for maximizing methane yield: An integrated machine learning and simulation-based economic analysis approach

This study employs machine learning (ML) algorithms, including multiple linear regression (MLR), decision tree (DT) and support vector regression (SVR) to predict the methane yield from the anaerobic co-digestion (ACoD) of palm oil mill effluent (POME) and decanter cake (DC) in an industry-scale anaerobic covered lagoon. Results showed that the DT model outperformed the other models with a high R2 value of 0.9763 and the lowest MAE, MSE, and RMSE values. It exhibited over 95 % similarity to the actual results, validating its effectiveness in capturing real-world scenarios. Optimisation was conducted using response surface methodology (RSM) to achieve maximum biogas production (14,245 m3/day) and methane yield (0.285 Nm3 CH4/kg CODremoved), where the optimal range of pH, organic loading rate (OLR) and dilution ratio of DC were found to be 6.83–6.94, 0.82–0.83 kg COD/m3. day and 0.09–0.11 respectively. The ACoD process was simulated, and an economic analysis was performed using SuperPro Designer v10.6. ACoD of POME and DC was more economically viable than mono-digestion of POME, with a 43.16 % improvement in return on investment (ROI), considering the trade-off between the additional cost of pre-treating DC and the additional revenue from improved biogas production using ACoD.

Preparation of Cellulose Nanofibrils with the Pretreatments using Inexpensive Protic Ionic Liquids based on Dimeric Oxalic Acid Anions

AbstractPreparation of cellulose nanofibrils (CNFs) with the pretreatments using alkanolamine‐based protic ionic liquids (PILs) with dimeric oxalic acid anions ([(HOA)(H2OA)]−) was fully investigated. The cation type [ethanolamine ([MEA]+), diethanolamine ([DEA]+), triethanolamine ([TEA]+)], and water addition greatly influenced the CNF yields. Under the pretreatment conditions of 110 °C and 3 h, the CNF yields with different PIL‐based systems followed the order: [MEA][(HOA)(H2OA)]&gt;[DEA][(HOA)(H2OA)]&gt;[TEA][(HOA)(H2OA)], similar to their swelling capacities. The highest CNF yield of 85.0 % was obtained after the pretreatment with [MEA][(HOA)(H2OA)]‐water containing 30 wt % PILs. The optimal pH range of PILs‐water was 1.10–1.15. The good recyclability indicated that these inexpensive PILs can be employed as a simple and efficient pretreatment system for preparing CNFs. The physicochemical properties of the prepared CNFs were greatly changed by varying the PILs’ pretreatment systems. The thermal stability of CNFs was intimately connected with the crystalline structures and hydrogen bonding modes.

Stabilization of metal and metalloids from contaminated soils using magnesia-based tundish deskulling waste from continuous steel casting

This study presents a groundbreaking exploration into the potential use of refractory tundish deskulling waste (TUN), a magnesium oxide-based by-product from continuous steel casting, as a stabilizing agent for remediating metal and metalloids contaminated soils. Up-flow column horizontal percolation tests were conducted to measure the concentrations of metals and metalloids, pH, and electrical conductivity (EC) in the leachates of two different combinations of contaminated soil and stabilizer (95–5 wt% and 90–10 wt%). The effectiveness of TUN as a soil-stabilizing agent for contaminated soils with metals and metalloids was evaluated by comparing its leachates with those obtained from a sample of a well-established low-grade magnesium oxide (LG-MgO) by-product, which underwent the same testing procedure.The findings revealed a significant correlation between the mobility of the examined metals and metalloids, and the water-soluble or acid phase of the contaminated soil, primarily governed by precipitation-solution reactions. While the stabilizing impact on non-pH-dependent metals, particularly redox-sensitive oxyanions, was less pronounced, both MgO-based stabilizers exhibited a favourable influence on soil pH-dependent metals and metalloids. They achieved this by establishing an optimal pH range of approximately 9.0–10.5, wherein the solubility of metal (hydr)oxides is minimized. Notably, metals like Zn and Cu, which have high leaching potential, experienced a remarkable reduction in leaching - Zn by over 99% and Cu by around 97% - regardless of the stabilizer content.In a broader context, this research champions the principles of the circular economy by offering a technical remedy for treating soils contaminated with pH-dependent metals and metalloids. The proposed solution harnesses industrial waste - currently relegated to landfills - as a resource, aligning with sustainable practices and environmental responsibility.

Novel Microsynthesis of High-Yield Gold Nanoparticles to Accelerate Research in Biosensing and Other Bioapplications.

Gold nanoparticles (AuNPs) exhibit unique properties that make them appealing for applications in biosensing and other emerging fields. Despite the availability of numerous synthesis methods, important questions remain to be addressed regarding the volume effect on the synthesis yield and quality of AuNPs in the light of biosensing research. The present study addresses these issues by developing a novel microvolumetric citrate-reduction method to improve the synthesis of AuNPs, which were characterized by electronic microscopy, energy dispersive spectroscopy, zeta potential and colorimetric analysis. A comparison of the novel microsynthesis method with the standard Turkevich method demonstrated its superior performance in terms of yield, monodispersity, rapidity (in one step), reproducibility, and stability. The analytical behavior of AuNPs-based aptasensors prepared by microsynthesis was investigated using kanamycin detection and showed higher reproducibility and improved detection limits (3.4 times) compared to those of Turkevich AuNPs. Finally, the effect of pH was studied to demonstrate the suitability of the method for the screening of AuNP synthesis parameters that are of direct interest in biosensing research; the results showed an optimal pH range between 5.0 and 5.5. In summary, the approach described herein has the potential to improve research capabilities in biosensing, with the added benefits of lowering costs and minimizing waste generation in line with current trends in green nanotechnology.

Genome sequencing and metabolic network reconstruction of a novel sulfur-oxidizing bacterium Acidithiobacillus Ameehan.

Sulfur-oxidizing bacteria play a crucial role in various processes, including mine bioleaching, biodesulfurization, and treatment of sulfur-containing wastewater. Nevertheless, the pathway involved in sulfur oxidation is highly intricate, making it complete comprehension a formidable and protracted undertaking. The mechanisms of sulfur oxidation within the Acidithiobacillus genus, along with the process of energy production, remain areas that necessitate further research and elucidation. In this study, a novel strain of sulfur-oxidizing bacterium, Acidithiobacillus Ameehan, was isolated. Several physiological characteristics of the strain Ameehan were verified and its complete genome sequence was presented in the study. Besides, the first genome-scale metabolic network model (AMEE_WP1377) was reconstructed for Acidithiobacillus Ameehan to gain a comprehensive understanding of the metabolic capacity of the strain.The characteristics of Acidithiobacillus Ameehan included morphological size and an optimal growth temperature range of 37-45°C, as well as an optimal growth pH range of pH 2.0-8.0. The microbe was found to be capable of growth when sulfur and K2O6S4 were supplied as the energy source and electron donor for CO2 fixation. Conversely, it could not utilize Na2S2O3, FeS2, and FeSO4·7H2O as the energy source or electron donor for CO2 fixation, nor could it grow using glucose or yeast extract as a carbon source. Genome annotation revealed that the strain Ameehan possessed a series of sulfur oxidizing genes that enabled it to oxidize elemental sulfur or various reduced inorganic sulfur compounds (RISCs). In addition, the bacterium also possessed carbon fixing genes involved in the incomplete Calvin-Benson-Bassham (CBB) cycle. However, the bacterium lacked the ability to oxidize iron and fix nitrogen. By implementing a constraint-based flux analysis to predict cellular growth in the presence of 71 carbon sources, 88.7% agreement with experimental Biolog data was observed. Five sulfur oxidation pathways were discovered through model simulations. The optimal sulfur oxidation pathway had the highest ATP production rate of 14.81 mmol/gDW/h, NADH/NADPH production rate of 5.76 mmol/gDW/h, consumed 1.575 mmol/gDW/h of CO2, and 1.5 mmol/gDW/h of sulfur. Our findings provide a comprehensive outlook on the most effective cellular metabolic pathways implicated in sulfur oxidation within Acidithiobacillus Ameehan. It suggests that the OMP (outer-membrane proteins) and SQR enzymes (sulfide: quinone oxidoreductase) have a significant impact on the energy production efficiency of sulfur oxidation, which could have potential biotechnological applications.

Nitrite production mechanism and microbial evolution characteristic influenced by pH during partial denitrification (PD) process

Partial denitrification (PD) has been proved technically feasible and economically favorable to produce nitrite (NO2--N) for anammox. To obtain stable NO2--N accumulation, the effects of pH (6.0, 7.5, 9.0, 10.0) on nutrient removal mechanism and microbial community evolution were investigated. Higher pH benefited PD performance with the optimal NO2--N and nitrate-to-nitrite transformation ratio (NTR) reaching to 43.50 mg/L, 81.64% at pH= 9.0 although slight NO2--N inhibition occurred caused by biomass loss and proton deficiency at pH= 10.0. Batch testes showed the same change trends of NTR (pH=9.0 >pH=7.5 >pH=6.0 >pH=10.0), where pH and oxidation reduction potential (ORP) also proved the “NO2--N knee” as pH varied around 7.5–9.0. The denitrification kinetic proved the closely relationship among carbon consumption rate (CCR), poly-β-hydroxyalkanoates transformation rate (PTR), NO2--N accumulation rate (N2AR), NO2--N reduction rate (N2RR) and nitrate (NO3--N) reduction rate (N3RR) although COD release, nitrogen loss and floc disintegration were observed under different pH conditions. Meanwhile, more aggregated microbial compositions formed (562–605 OTUs) at the optimal pH range of 7.5–9.0, where Terrimonas, norank_f_A4b, Defluviicoccus, Hyphomicrobium, norank_f_Blastocatellaceae, and OLB13 were the main contributors for NO2--N maintenance, with the proportions accounting for 35.29–39.60%.

PH determination as a quality standard for the elaboration of oral liquid compounding formula

ObjectivepH is a critical factor for all those medications prepared as aqueous liquid forms, because it has an impact on the solubility of the molecule, determining the stability of medications, the biological tolerability of the formulation, and the activity of the molecule. The objective of this study is to determine the optimum pH range for the oral liquid formulations more frequently prepared at the Pharmacy Unit, in order to standardize and incorporate said value into the standard protocols of action as a quality control criterion. MethodThe study was conducted in three stages. The first stage consisted in a retrospective study of the records of preparation of those oral liquid formulations prepared at least 5 times since January, 2015 to December, 2016, in our Pharmacy Unit; the main value and standard deviation of the pH values recorded for each formulation were calculated. In a second stage, there was a bibliographic search in order to understand the pH for the maximum stability of the molecule, and to confirm if this characteristic was recorded as a requirement for quality control in the procedures described in the formulation guidelines. In the third stage, it was confirmed if the pH values determined coincided with the maximum stability pH described in literature, and acceptance ranges were established. ResultsIn total, 31 formulations were reviewed (14 solutions / 17 suspensions). The maximum stability pH value was known for 19 (61.3%) of the molecules and/or oral liquid formulations evaluated; 15 (78.9%) of these were within this range, and the remaining 4 (21.1%) presented a standard deviation of ± 0.5 regarding the pH value referenced in the bibliography. The pH range for the same standard work procedure ranged between 0.32 and 1.51. An acceptance pH range of ± 0.75 was determined as quality control. ConclusionsAn optimal pH range has been determined for the 31 oral liquid formulations more widely prescribed in our hospital. This characteristic should be part of the galenic validation for these preparations, as well as of its routine quality control, in order to ensure their quality and efficacy.

Simultaneous removal of antibiotics and metal oxoanions from aqueous solution by Ce-doped UiO-66: Removal mechanisms and solid phase extraction

Simultaneous removal of coexistent antibiotics and heavy metals from wastewater is crucial for the safety and quality of aquatic ecosystems. Metal-organic frameworks (MOFs) are promising candidates for wastewater remediation due to their robust and tailorable pore structure, but the removal mechanisms for the synchronous removal of multiple pollutants remain unclear. Herein, Ce-doped UiO-66 (Ce-UiO-66) was prepared and utilized to efficiently remove multiple pollutants from water under single and mixed pollutant systems. After Ce doping, the adsorption amounts of pefloxacin (PEF), tetracycline (TC) and Cr(VI) reached 476.3 mg/g, 368.6 mg/g and 58.3 mg/g, respectively, which were 5–10 times higher than those of pristine UiO-66. In the binary system, the presence of Cr(VI) broadened the optimal adsorption pH range of PEF, and Cr(VI) adsorption was enhanced in the presence of low concentrated PEF. Various interactions contributed together to the excellent adsorption ability of Ce-UiO-66. The contribution degree of some interactions was as follows: (1) for PEF adsorption, at 2.0 < pH < 5.0, complexation bonding (CB) accounted for 40–95% of the total uptake; at 5.0 < pH < 10.0, the contribution of electrostatic attraction (EA) increased to approximately 5–36% while CB decreased to 32–50%; (2) for TC adsorption, at 2.0 < pH < 7.0, CB accounted for 50–81% of the total uptake; at 7.0 < pH < 10.0, the contribution of CB increased to approximately 30% and EA at 2.0 < pH < 10.0 accounted for 5–14% of the total uptake; and (3) for Cr(VI) adsorption, at 2.0 < pH < 10.0, EA and CB dominated the adsorption, together accounting for 50–100% of the total uptake. More importantly, the order of functional groups participating in adsorption was revealed by 2D-FTIR-COS analysis. Ce-UiO-66 showed excellent recycling ability and was efficient in removing multiple pollutants from various actual water samples. Moreover, simple solid phase extraction (SPE) experiments revealed that Ce-UiO-66 obtained excellent adsorption capacities of 474.63 mg/g and 261.8 mg/g for PEF and TC, respectively. This study provides a new paradigm for devolving highly robust adsorbents for wastewater treatment.

Adsorption of uranium(VI) by natural vermiculite: Isotherms, kinetic, thermodynamic and mechanism studies

Human activities such as mining uranium resources, hydrometallurgy, and nuclear fuel preparation inevitably produce wastewater sludge containing radionuclides, posing a severe threat to the environment around the production site. Natural clay minerals have been widely used in groundwater pollution remediation because of their high cation exchange capacity. Through static batch experiments, the optimal pH range of vermiculite for U(VI) adsorption was 6–8,the maximum adsorption capacity was 1.62 × 10−5 mol g−1. The kinetic adsorption results indicated that the adsorption mode was mainly multilayer non-homogeneous chemisorption. In addition, the adsorption of vermiculite on U(VI) was found to be a heat absorption process according to the thermodynamic model fitting, and the spontaneous reactivity of U(VI) adsorption on vermiculite surface was positively correlated with temperature and negatively correlated with the initial concentration of U(VI). Combined with SEM-EDS and FT-IR results, the adsorption process of vermiculite on U(VI) is mainly an ion exchange and complexation reaction, and U(VI) is removed in the form of ≡ SUOU22+ or ≡ SOUO2OH, etc., by XPS means. The results of this study not only investigated the adsorption behavior and mechanism of natural vermiculite in groundwater contaminated with simulated uranium but also provided theoretical support for its feasibility in remediating uranium-polluted groundwater.

Recent advances in enzymatic properties, preparation methods, and functions of glycoside hydrolase from Bifidobacterium: a review.

Bifidobacterium is a major probiotic of intestinal gut flora and exerts many physiological activities, and it is widely applied in the fields of food and medicine. As an important part of Bifidobacterium, glycoside hydrolase plays a role in its physiological activity. With the continuous development and improvement of genetic engineering technology, research on this type of enzyme will play a crucial role in promoting the further development of Bifidobacterium in the field of probiotics. In this review, the preparation methods, enzymatic properties, and functions of glycoside hydrolase extracted from Bifidobacterium are described and summarized. The common method for preparing glycoside hydrolase derived from Bifidobacterium is heterologous expression in Escherichia coli BL21. The optimal pH range for these glycoside hydrolase enzymes is between 4.5 and 7.5; the optimal temperature is between 30 and 50 °C, which is close to the optimal growth condition of Bifidobacterium. Based on substrate specificity, these glycoside hydrolase could hydrolyze synthetic substrates and natural oligosaccharides, including a series of pNP artificial substrates, disaccharide, and trisaccharides, while they have little ability to hydrolyze polysaccharide substrates. This review will be expected to provide a basis for the development of Bifidobacterium as a probiotic element.

Fully automated radiolabeling of [68Ga]Ga-EMP100 targeting c-MET for PET-CT clinical imaging

Backgroundc-MET is a transmembrane receptor involved in many biological processes and contributes to cell proliferation and migration during cancer invasion process. Its expression is measured by immunehistochemistry on tissue biopsy in clinic, although this technique has its limitations. PET-CT could allow in vivo mapping of lesions expressing c-MET, providing whole-body detection. A number of radiopharmaceuticals are under development for this purpose but are not yet in routine clinical use. EMP100 is a cyclic oligopeptide bound to a DOTA chelator, with nanomolar affinity for c-MET. The aim of this project was to develop an automated method for radiolabelling the radiopharmaceutical [68Ga]Ga-EMP100.ResultsThe main results showed an optimal pH range between 3.25 and 3.75 for the complexation reaction and a stabilisation of the temperature at 90 °C, resulting in an almost complete incorporation of gallium-68 after 10 min of heating. In these experiments, 90 µg of EMP-100 peptide were initially used and then lower amounts (30, 50, 75 µg) were explored to determine the minimum required for sufficient synthesis yield. Radiolysis impurities were identified by radio-HPLC and ascorbic acid and ethanol were used to improve the purity of the compound. Three batches of [68Ga]Ga-EMP100 were then prepared according to the optimised parameters and all met the established specifications. Finally, the stability of [68Ga]Ga-EMP100 was assessed at room temperature over 3 h with satisfactory results in terms of appearance, pH, radiochemical purity and sterility.ConclusionsFor the automated synthesis of [68Ga]Ga-EMP100, the parameters of pH, temperature, precursor peptide content and the use of adjuvants for impurity management were efficiently optimised, resulting in the production of three compliant and stable batches according to the principles of good manufacturing practice. [68Ga]Ga-EMP100 was successfully synthesised and is now available for clinical development in PET-CT imaging.

Chiral resolution of (±)-flurbiprofen using molecularly imprinted hydrazidine-modified cellulose microparticles

Flurbiprofen (FP) is one of the non-steroidal anti-inflammatory drugs (NSAIDs) commonly used to treat arthritic conditions. FP has two enantiomers: S-FP and R-FP. S-FP has potent anti-inflammatory effects, while R-FP has nearly no such effects. Herein, molecularly imprinted microparticles produced from hydrazidine-cellulose (CHD) biopolymer for the preferential uptake of S-FP and chiral resolution of (±)-FP were developed. First, cyanoethylcellulose (CECN) was synthesized, and the -CN units were transformed into hydrazidine groups. The developed CHD was subsequently shaped into microparticles and ionically interacted with the S-FP enantiomer. The particles were then imprinted after being cross-linked with glutaraldehyde, and then the S-FP was removed to provide the S-FP enantio-selective sorbent (S-FPCHD). After characterization, the optimal removal settings for the S- and R-FP enantiomers were determined. The results indicated a capacity of 125 mg/g under the optimum pH range of 5–7. Also, S-FPCHD displayed a noticeable affinity toward S-FP with a 12-fold increase compared to the R-FP enantiomer. The chiral resolution of the (±)-FP was successfully attempted using separation columns, and the outlet sample of the loading solution displayed an enantiomeric excess (ee) of 93 % related to the R-FP, while the eluent solution displayed an ee value of 95 % related to the S-FP.

Natural Antibodies Produced in Vaccinated Patients and COVID-19 Convalescents Recognize and Hydrolyze Oligopeptides Corresponding to the S-Protein of SARS-CoV-2.

The S-protein is the major antigen of the SARS-CoV-2 virus, against which protective antibodies are generated. The S-protein gene was used in adenoviral vectors and mRNA vaccines against COVID-19. While the primary function of antibodies is to bind to antigens, catalytic antibodies can hydrolyze various substrates, including nucleic acids, proteins, oligopeptides, polysaccharides, and some other molecules. In this study, antibody fractions with affinity for RBD and S-protein (RBD-IgG and S-IgG) were isolated from the blood of COVID-19 patients vaccinated with Sputnik V. The fractions were analyzed for their potential to hydrolyze 18-mer oligopeptides corresponding to linear fragments of the SARS-CoV-2 S-protein. Here, we show that the IgG antibodies hydrolyze six out of nine oligopeptides efficiently, with the antibodies of COVID-19-exposed donors demonstrating the most significant activity. The IgGs of control donors not exposed to SARS-CoV-2 were found to be inactive in oligopeptide hydrolysis. The antibodies of convalescents and vaccinated patients were found to hydrolyze oligopeptides in a wide pH range, with the optimal pH range between 6.5 and 7.5. The hydrolysis of most oligopeptides by RBD-IgG antibodies is inhibited by thiol protease inhibitors, whereas S-IgG active centers generally combine several types of proteolytic activities. Ca2+ ions increase the catalytic activity of IgG preparations containing metalloprotease-like active centers. Thus, the proteolytic activity of natural antibodies against the SARS-CoV-2 protein is believed to be due to the similarity of catalytic antibodies' active centers to canonical proteases. This work raises the question of the possible physiological role of proteolytic natural RBD-IgG and S-IgG resulting from vaccination and exposure to COVID-19.

Review in Waste Tire Management-Potential Applications in Mitigating Environmental Pollution.

Increasing year-by-year vehicle production is related to the expanding volume of used tires; therefore, exploring waste management strategies is strongly recommended. The global tire market reached 2.27 billion units in 2021 and is expected to reach 2.67 billion units by 2027. Dumping tires in landfills can cause significant environmental impacts, so waste tire utilisation plays an important role. Predominantly, the following three directions are employed for waste tire disposal: retreading, energy recovery and material recovery. The review shows that used tires can remove environmental pollution from both aqueous solutions containing heavy metal ions, dyes, pharmaceutical compounds, and benzene, toluene, ethylbenzene and xylene (BTEX). Particularly high efficiency was achieved in the removal of dyes (72%), taking into account the high initial concentration of impurities. The adsorption process depends on multiple factors, including, in particular, the following: pH, initial concentration of pollution, contact time and the properties of the sorbent used. The optimal pH range was identified to be between 6 and 7. Considering the principles of circular economy as well as based on the current state of knowledge, it can be concluded that the solid fraction obtained from the combustion of waste tires can be practically utilised for various environmental purposes.

Improving physical stability of pea protein-based emulsions near the isoelectric point via polysaccharide complexation

Development of plant protein-based mildly acidic beverages remains challenging as the pH range falls near the protein isoelectric point, destabilizing emulsions. To overcome this problem, it was hypothesized that complexation between plant proteins and polysaccharides could provide emulsion stability in this critical pH range. Four different polysaccharides (sugar beet pectin, gum Arabic (GA), guar gum, gellan gum) were mixed separately with pea protein isolate (PPI) in 1:1 ratio, and the critical pH values for the formation of soluble complexes were determined. Heating the mixture widened the optimal pH range for soluble complexation for pectin-PPI and GA-PPI below the isoelectric point, which was then used to prepare 5 wt% O/W emulsions with an aqueous phase containing 0.5 wt% biopolymers at pH 8.0 and pH 4.5. Emulsion stability was characterized using droplet size, charge, visual observation, microstructure, and accelerated gravitational separation. PPI-only emulsions were stable at pH 8.0 but extensively destabilized at pH 4.5. The GA-PPI emulsions showed high stability at pH 8.0; however, at pH 4.5, the soluble complexes failed to provide a stable emulsion due to extensive droplet aggregation and phase separation. The emulsion prepared with a co-soluble pectin-PPI mixture at pH 8.0 also showed droplet aggregation and phase separation. The most improved emulsion stability (smallest droplet size, no aggregation) was observed for the pectin-PPI soluble complex at pH 4.5. Findings from this study showed that soluble complexes could be obtained at the desired pH range depending on the polysaccharide sources, which can stabilize O/W emulsions even near the protein's isoelectric point.