Immobilized Form Research Articles

Insight into γ-Irradiation-Induced Structure Evolution of Uranium(IV) Germanates as Crystalline Nuclear Waste Forms.

New kinds of crystalline waste forms with improved structural stability are desirable for actinide immobilization. In this work, using a molten salt method, two uranium(IV) germanate compounds, namely, K2UGe3O9 (1) and K2UGe2O7 (2), were synthesized, whose compositions consisted of trimeric and dimeric units of germanate, as well as tetravalent uranium, as proved by bond valence calculation and X-ray absorption spectra. Radiation stability assessment is further performed by γ-irradiation to assess the potential of as-synthesized uranium germanate compounds as nuclear waste forms. Powder X-ray diffraction and single-crystal diffraction analyses reveal that 1 remains stable within 1 MGy dosage and undergoes a significant structural change with increasing dosage at 2 MGy, leading to a transformation of 1 to 1-ir analogous to 2 in chemical structure. The underlying mechanism was further studied through a combination of different characterization techniques, including Raman, UV-vis, and electron paramagnetic resonance spectroscopies. Density functional theory calculations of 1 and 2 were also conducted to probe the coordination interaction of germanium and uranium with oxygen atoms. This work reports new crystalline uranium germanates by flux growth and, most importantly, provides insights into the irradiation stability of these materials, which will be beneficial to developing waste forms for long-term immobilization of radionuclides.

Modeling the Change in Amino Acid and Peptide Contents during the Aging of Bottled-Fermented Sparkling Wines by Image Processing Methods

In this study, natural sparkling wine was produced using a mixture (1:1) of Emir and Dimrit grapes harvested (Around the Urgup District of Turkey). The change of free amino acid and peptide contents in sparkling wine depending on the aging time and yeasts (free and immobilized forms of the Saccharomyces bayanus and Saccharomyces oviformis) used in the second fermentation stage were examined by image processing methods. The immobilized yeasts were determined as more than the free ones along the second fermentation. It was also determined that the yeast type does not have a significant effect on both the peptides and free amino acid contents of sparkling wines and these contents were divided into 3 classes from high to low by measuring separately along the aging time. The amino acid contents of sparkling wines reached the highest level between the 335th and 365th days of aging time and also exceeded the amino acid contents of base wine.

Single stage bi-substrate transglycosylation reaction for the synthesis of ascorbic acid 2 glucoside using immobilized α-glucosidase

Alpha glucosidases are multifunctional glycoside hydrolases with hydrolysis and transglycosylation ability. It can be utilized for the glycosidic bond synthesis or glycosylation of Ascorbic acid/Vitamin C to its stable analogue, Ascorbic acid 2 glucoside (AA2G), a compound with wide applications in cosmetics and pharma. The application of α-glucosidases for industrial scale transglycosylation is limited due to the low transglycosylation yield of free enzymes. Enzyme immobilization techniques could enable the development of efficient, reusable catalysts. Only a few glycoside hydrolases have been studied in immobilized form for transglycosylation reactions, and α-glucosidases are probably the least explored in this form. Transglycosylation activity of immobilized α-glucosidase from Aspergillus carbonarius BTCF 5 was studied for AA2G synthesis, where different immobilization techniques like calcium alginate encapsulation, adsorption on chitosan beads, covalent cross-linking on magnetic nanoparticles, and cross-linked enzyme aggregates (CLEA) were employed for the immobilization. The immobilization yield of calcium alginate encapsulated enzyme, enzyme immobilized on Fe-MNP support, enzyme immobilized on chitosan beads and as CLEA were 107%, 99%, 46% and 486%, respectively. CLEA was identified as the best immobilization technique for this bi-substrate reaction due to the high immobilization yield and activity retention (30% activity retained after 5 consecutive cycles). Enzyme immobilization increased the transglycosylation activity by 38%, yielding 118 mM AA2G against 72 mM by the free enzyme. This indicates the potential of immobilized α-glucosidase as a catalyst for synthesizing AA2G at an industrial scale.

Mortality risk factors for adult trauma patients treated with halo brace for cervical spine fracture

Introduction and objectivesHalo braces treat upper cervical spine fractures and serve as the most rigid form of external immobilization. Recently, halo braces have lost favor due to known complications and advances in surgical stabilization. This study aims to determine the contemporary incidence for use of halo braces and identify risk factors associated with mortality in trauma patients undergoing halo brace for cervical spine fractures. Materials and methodsThe 2017–2019 Trauma Quality Improvement Program Database was queried for patients ≥18 years-old with a cervical spine fracture undergoing halo brace. Patients sustaining penetrating trauma and severe torso injuries (abbreviated injury scale >3 for the abdomen or thorax) were excluded. Bivariate and multivariable logistic regression analyses were performed. ResultsFrom 144,434 patients with a cervical spine fracture, 272 (0.2%) underwent halo brace and 14 (5%) of these died. Those who died were older (73.5 vs. 53 years-old, p = 0.011) and had higher rates of hypertension (78.6% vs 33.1%, p < 0.001) and chronic kidney disease (14.3% vs. 1.2%, p < 0.001). Glasgow Coma Scale ≤8 (46.2% vs. 8.2%, p < 0.001) and cervical spinal cord injury (71.4% vs. 21.3%, p < 0.001) were more common in patients who died. In addition, those who died more often sustained respiratory complications (7.1% vs. 0.4%, p = 0.004) and sepsis (7.1% vs. 0.4%, p = 0.004). On multivariable logistic regression analysis, only Glasgow Coma Scale ≤8 (OR 19.77, 3.04–128.45, p = 0.002) was associated with increased mortality. ConclusionsOnly 5% of cervical spine fracture patients undergoing halo brace died. Respiratory complications and sepsis were more common in those who died. On multivariable analysis only Glasgow Coma Scale ≤8 remained an independent associated risk factor for mortality.

Harnessing the hidden environmental power of Bjerkandera adusta laccase: Sustainable production, green immobilization, and eco-friendly decolorization of mixed azo dyes

This research unveils the untapped potential of laccase, derived from the Bjerkandera genus, utilizing it in an immobilized system aimed at detoxifying harmful azo dye effluents from the textile industry, thus contributing to environmental protection. Marking a pioneering achievement, we recorded the highest laccase activity at 94.52 U/g cultivating B. adusta's mycelium on brewer's spent grain, enhanced with lignocellulosic waste, under meticulously optimized conditions −2.69 g of alkali-pretreated beech sawdust, 0.91 g of cypress cone, and 8-day incubation period. The harvested laccase was subjected to an immobilization process on alkali-pretreated beech sawdust, where, through optimization, we established the ideal conditions (30 mg of carrier, pH 7, and 3.5 h), achieving an immobilization efficiency of 72.24% with a residual activity of 57.64%. Remarkably, both free and immobilized forms of the B. adusta TMF1 laccase enzyme demonstrated formidable efficacy in decolorizing a mix of three distinct azo dyes (Orange G, Eriochrome Black T, and Congo Red), eliminating over 63% of the coloration within just 30 min. The immobilized laccase showed consistent performance across four decolorization cycles. Moreover, the breakdown products of the azo dye mix were analyzed using the HPLC method, complemented by evaluations of potential antimicrobial activity, phytotoxicity and cytotoxicity, revealing a non-toxic composition without cytotoxicity, highlighting the process's safety for environmental release. The significance of this research is reflected in the distinguished construction of a green biocatalyst acting as a stable and time-efficient in remediation of targeted azo dye pollution from the textile industry following the principles of circular economy.

Robust peroxidase from Bacillus mojavensis TH309: Immobilization on walnut shell hydrochar and evaluation of its potential in dye decolorization

Peroxidases have received considerable attention as a cost-effective and environmentally friendly catalyst for bioremediation. Their rapid activity loss under harsh environmental conditions and inability to be used repetitively limit their exploitation in real-world wastewater treatment. First, a peroxidase was produced extracellularly by Bacillus mojavensis TH309 and purified 8.12-fold with a final yield of 47.10 % using Sephadex G-100 superfine resin. The pure peroxidase (BmPer) possessed a relatively low molecular weight of ∼21 kDa and was active against L-DOPA on acrylamide gel after electrophoresis. BmPer was immobilized by adsorption functionalized walnut shell hydrochar (WsH) with 61.99 ± 1.34 % efficiency and 37.07 ± 4.16 % activity loss. BmPer and its immobilized form (WsH-BmPer) exhibited maximum activity at 50 °C and pH 9. WsH-BmPer exhibited 3.23-, 2.37-, 1.65-, and 2.25-fold longer half-life than BmPer at 50, 60, 70, and 80 °C, respectively. Immobilization significantly enhanced the stability of the enzyme under acidic conditions. BmPer and WsH-BmPer showed maximal activity in the presence of 1 % salt and retained more than 85 % of their activity even after pre-incubation with 2.5 M salt for 60 min at 50 °C. Their catalytic efficiency was significantly stimulated by pre-incubation with Triton X-100 (1 mM), Tween20 (1 mM), and Mg2+ (1 and 10 mM). Immobilization strongly reduced the loss of activity caused by inhibitors including Ba2+, Hg2+, and Cu2+. Moreover, both forms of the enzyme were compatible with solvents. The Michaelis constant (Km) values of BmPer and WsH-BmPer were 0.88 and 2.66 mM for 2,4 DCP, respectively. WsH-BmPer peroxidase maintained about 82 % and 85 % of its activity when stored at 4 °C for 30 days and reused for up to 10 cycles, respectively. Furthermore, it decolorized Cibacron red (CR), Poly R-478 (PR), Remazol Brilliant Blue R (RBBR), and Methyl red (MR) dyes by 60.13 %, 91.34 %, 86.41 %, and 50.51 % within 60 min, respectively.

Comparative Analysis of Rehabilitation Strategies Following Ankle Fracture Surgery: A Systematic Review.

Considering various forms of immobilization that enable early weight-bearing or exercise initiation, rehabilitation following an ankle fracture can start shortly after the fracture has been repaired. Alternatively, after the period of immobility, physical or manual therapy may be used to begin rehabilitation. This systematic review aimed to compare different rehabilitation strategies after ankle fracture surgery. Four different databases (Scopus, Web of Science, PubMed/MEDLINE (Medical Literature Analysis and Retrieval System Online, and Google Scholar) were used to retrieve the relevant data using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Randomized and quasi-randomized controlled trials involving people undergoing every type of rehabilitation therapy following an ankle fracture surgerywere taken into consideration. The main result was a limitationin activities. Adverse events and impairments were instances of such secondary outcomes. A total of 31 studies were found to be eligible for inclusion in this systematic review. The use of exercise and a removable form of immobilization during the immobilization phase to enhance activity limitation is supported by very little evidence. The patient's capacity to adhere to this treatment plan is crucial due to the possible higher risk. To support the available data, more carefully planned and sufficiently powered clinical trials must be conducted.

Comparison of the Effects of Postoperative Arm Restraints and Mittens on Cleft Lip Scar Quality after Primary Repair.

Introduction: Postoperative management following primary cleft lip repair varies across institutions, cleft care teams, and individual surgeons. Postoperative precautions employed after cleft lip repair include dietary restrictions, pacifier limitations, and immobilization, with arm restraints long being used. Yet, restraint distress has led to the exploration of other forms of immobilization. Thus, this study aims to assess cleft lip scar quality and complication rates after postoperative immobilization with arm restraints versus hand mittens. Methods: A retrospective review of patients with unilateral cleft who underwent primary repair with the senior surgeon was done. Data on demographics, surgical characteristics, and immobilization utilized were gathered. A survey with pictures of postoperative scars were sent to laypeople who assessed scar quality with Modified Scar-Rating Scale scores for surface appearance, height, and color of the scar tissue. Statistical analysis was carried out for significance. Results: Twenty-eight patients with a unilateral cleft underwent arm restraints after primary lip repair, and twenty-seven utilized mittens. In total, 42 medical students completed the scar assessment. Photographs were taken an average of 23.9 (±5.8) and 28.2 (±11.9) months postoperatively in the restraint and mitten groups, respectively (p = 0.239). There were no statistically significant differences in scores between scar surface, height, color, or overall scar appearance. Complication rates were also similar between groups. Conclusions: Arm restraints appear to have no additional benefit relative to scar quality, as compared to mittens. Considering the arm restraints' burden of care, mittens should be considered as a measure to protect the lip after primary repair.

Amphichdiral enhancement on singlet oxygen generation and stable thallium immobilization using iron-driven copper oxide

Thallium (Tl) as a prominent priority contaminant in aquatic environment necessitates rigorous regulation. However, limited horizon devotes the impact of selective oxidation on the process of thallium purification. In this study, selective active radical of singlet oxygen (1O2) was continually generated for Tl(Ⅰ) oxidation accomplished with efficient Tl(Ⅲ) immobilization using iron-driven copper oxide (CuFe)/peroxymonosulfate (PMS). Fe-doping changed the active center of electronic structure for enhancing the catalytic and adsorptive reactivities, and installed magnetism for solid-liquid separation. Rapid reaction rate (0.253 min−1) coupled with vigorous elimination efficiency (98.32%) relied on electrostatic attraction, surface complexation, and H-bond interaction. EPR and XPS analyses demonstrated that the synergistic effects of ≡ Cu(Ⅰ)/≡Cu(Ⅱ) and ≡ Fe(Ⅲ)/≡Fe(Ⅱ) redounded to the sustained generation of 1O2 through the pathway of PMS → •O2− → 1O2, and 1O2 exploited an advantage to selectively oxidize Tl(Ⅰ) to Tl(Ⅲ). 3D isosurface cubic charts revealed that the immobilizing ability of Tl(Ⅲ) hydrate for CuFe was notably superior to that of Tl(Ⅲ) hydrate for CuO and Tl(Ⅰ) hydrate for CuO/CuFe, which further attested surface reactivity promoted stable immobilization form. This work develops the continuous generation of 1O2 and stable immobilization with the goal of efficiently cleansing Tl-containing wastewater.

Evaluation of batch and fed-batch rotating drum biological contactor using immobilized Trametes hirsuta EDN082 for non-sterile real textile wastewater treatment

White rot fungi, in both free and immobilized forms, excel in degrading dyes through adsorption and enzyme degradation. However, existing studies often focus on synthetic wastewater within sterile lab conditions. This study extends the application of Trametes hirsuta EDN082 immobilized in light-expanded clay aggregates (myco-LECAs) packed in a rotating drum biological contactor (RDBC) for treating real textile wastewater under non-sterile conditions to simulate industrial treatment scenarios. Experiments included batch and fed-batch RDBC to assess the impact of additional glucose and stepwise dilution on quality indicators like pH, chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), color, and solids. In fed-batch RDBC with 0.5 % additional glucose, myco-LECAs achieved a maximum of 94 % COD removal (day 15), 99 % NH4+-N reduction (day 33), and 39 % decolorization without additional glucose. In comparison, myco-LECAs in batch RDBC highlighted 89 % NH4+-N reduction in 9 days without pH adjustment or additional nutrients. The pH maintained between 6−9, with no toxicity in Artemia salina, and 97−100 % removal of E. coli. Compared to Indonesian textile wastewater discharge limits, the technology achieved effective ammonia removal below 8 mg/L. This suggests that immobilized T. hirsuta EDN082 in LECAs presents a viable, non-sterile treatment for real textile wastewater.

Low temperature fabrication of Ba0.9Cs0.3Cr2.1Ti5.9O16 ceramic waste form for cesium immobilization using Bi2O3 as sintering aid

In this paper, we present a productive low-temperature fabrication of Cs-hollandite ceramics by adding Bi2O3 as a sintering aid to achieve high cesium retention. The effects of Bi2O3 addition on the phase composition, crystal structure and aqueous stability of the stoichiometric Ba0.9Cs0.3Cr2.1Ti5.9O16 ceramic waste form were investigated. It was found that adding Bi2O3 can effectively reduce the sintering temperature and promote densification of Cs-containing hollandite products. The Cs-hollandite ceramic with 2 wt% Bi2O3 sintered at 1000 °C showed a single phase with > 98 % cesium retention, which was ∼ 200 °C lower and ∼ 11 % retention rate higher than those of reported Cs-bearing hollandite. Moreover, the leached sample remained stable tetragonal structure, the LRCs was in the order of 10-3 g·m-2·d-1 after 28 days and the leaching indexes > 8, exhibiting good aqueous stability. This route can be considered as a promising solution to prevent cesium loss for incorporating the cesium waste in ceramic hosts.

The study of the influence of &lt;i&gt;Thlaspi arvense&lt;/i&gt; L. on the characteristics of the reproductive system of male rats

Introduction. The development of new effective and safe herbal medicines capable of having a positive effect on reproductive status is an urgent task of domestic pharmacy. Medicinal plants are considered as alternative therapies aimed at increasing testosterone levels and fertility in men. The arsenal of medicinal plants used in traditional medicine for the treatment of diseases in men is mainly represented by phytoadaptogens, most of which have a small resource potential in Russia, therefore, it is relevant to search for plants with a sufficient raw material base and with the potential for cultivation. Thlaspi arvense L. is a promising medicinal plant, as it is widely used in folk medicine as a diuretic, anti-inflammatory, diaphoretic, antihistamine, hemostatic, astringent, has a positive effect on the processes of spermatogenesis and is widely distributed in our country. However, information on the chemical composition and biological activity of Thlaspi arvense L. they are insufficient, which shows the relevance of its further more detailed study in order to substantiate the possibility of application in practical medicine and solutions to the issues of standardization of medicinal plant raw materials.Aim. The study of the influence of Thlaspi arvense L. on the characteristics of the reproductive system of male rats.Materials and methods. The object of the study was an infusion of herbа Thlaspi arvense L. The features of the reproductive behavior of male rats after 21-day administration of the infusion of grass yarutka field were studied using tests that allow quantifying the severity of sexual motivation and sexual activity of males. The viability of spermatozoa in the ejaculate of rats was assessed, the total number of spermatozoa (ACS, million), degenerative and immobile forms (%) was calculated. Morphophysiological parameters of spermatogenesis of rats of control and experimental groups of animals were studied using classical histological methods. The concentration of testosterone in the blood serum of experimental groups of animals was determined by the enzyme immunoassay.Results and discussion. The results obtained allow us to conclude that the fertility of rats has increased against the background of the course administration of the infusion of herbа Thlaspi arvense L., as evidenced by an increase in the testosterone content in the blood, improvement of spermogram indicators and morphophysiological characteristics of spermatogenesis in the testicles of rats. The use of the infusion of herbа Thlaspi arvense L. has a protective effect on spermatogenesis. An increase in the thickness of the spermatogenic epithelium, the diameter of the cross-section of the convoluted seminal tubules and the index of spermatogenesis compared with the control group of animals was revealed. The positive effect of Thlaspi arvense L. on indicators of sexual motivation and sexual activity of male rats is shown.Conclusion. Thlaspi arvense L. is a promising medicinal plant, as it is able to have a positive effect on libido, the number and mobility of spermatozoa, the production of sex hormones, spermatogenesis, as well as on the pituitary-gonadal axis, which is associated with the content of a complex of biologically active substances in it.

A New Approach in Lipase-Octyl-Agarose Biocatalysis of 2-Arylpropionic Acid Derivatives.

The use of lipase immobilized on an octyl-agarose support to obtain the optically pure enantiomers of chiral drugs in reactions carried out in organic solvents is a great challenge for chemical and pharmaceutical sciences. Therefore, it is extremely important to develop optimal procedures to achieve a high enantioselectivity of the biocatalysts in the organic medium. Our paper describes a new approach to biocatalysis performed in an organic solvent with the use of CALB-octyl-agarose support including the application of a polypropylene reactor, an appropriate buffer for immobilization (Tris base-pH 9, 100 mM), a drying step, and then the storage of immobilized lipases in a climatic chamber or a refrigerator. An immobilized lipase B from Candida antarctica (CALB) was used in the kinetic resolution of (R,S)-flurbiprofen by enantioselective esterification with methanol, reaching a high enantiomeric excess (eep = 89.6 ± 2.0%). As part of the immobilization optimization, the influence of different buffers was investigated. The effect of the reactor material and the reaction medium on the lipase activity was also studied. Moreover, the stability of the immobilized lipases: lipase from Candida rugosa (CRL) and CALB during storage in various temperature and humidity conditions (climatic chamber and refrigerator) was tested. The application of the immobilized CALB in a polypropylene reactor allowed for receiving over 9-fold higher conversion values compared to the results achieved when conducting the reaction in a glass reactor, as well as approximately 30-fold higher conversion values in comparison with free lipase. The good stability of the CALB-octyl-agarose support was demonstrated. After 7 days of storage in a climatic chamber or refrigerator (with protection from humidity) approximately 60% higher conversion values were obtained compared to the results observed for the immobilized form that had not been stored. The new approach involving the application of the CALB-octyl-agarose support for reactions performed in organic solvents indicates a significant role of the polymer reactor material being used in achieving high catalytic activity.

Modified polymeric biomaterials with antimicrobial and immunomodulating properties

The modification of the surgical polypropylene mesh and the polytetrafluoroethylene vascular prosthesis with cecropin A (small peptide) and puromycin (aminonucleoside) yielded very stable preparations of modified biomaterials. The main emphasis was placed on analyses of their antimicrobial activity and potential immunomodulatory and non-cytotoxic properties towards the CCD841 CoTr model cell line. Cecropin A did not significantly affect the viability or proliferation of the CCD 841 CoTr cells, regardless of its soluble or immobilized form. In contrast, puromycin did not induce a significant decrease in the cell viability or proliferation in the immobilized form but significantly decreased cell viability and proliferation when administered in the soluble form. The covalent immobilization of these two molecules on the surface of biomaterials resulted in stable preparations that were able to inhibit the multiplication of Staphylococcus aureus and S. epidermidis strains. It was also found that the preparations induced the production of cytokines involved in antibacterial protection mechanisms and stimulated the immune response. The key regulator of this activity may be related to TLR4, a receptor recognizing bacterial LPS. In the present study, these factors were produced not only in the conditions of LPS stimulation but also in the absence of LPS, which indicates that cecropin A- and puromycin-modified biomaterials may upregulate pathways leading to humoral antibacterial immune response.

Bioremediation of tannery wastewater using UV-treated bacteria in the free and immobilized form

Bioremediation of tannery wastewater using UV-treated bacteria in the free and immobilized form

Lipases: market study and potential applications of immobilized derivatives

AbstractThe enzyme market is growing constantly, and lipases, in their free and immobilized forms, constitute an important part of this market. This study aimed to analyze and discuss current market scenarios using data from the literature, focusing on lipases and the feasibility of their use in the immobilized form. It also compares the cost of biodiesel production using two commercial lipases: Eversa Transform 2.0 (free lipase) and Novozyme 435 (immobilized lipase). The results show that the European and North American enzyme markets are the most prominent worldwide, with Denmark and the USA as the major exporters and importers, respectively. Lipases can be used in a wide variety of fields, and immobilization brings many advantages to this enzyme class. Finally, we show the use of immobilized enzymes and lipases in biorefinery and food industries and carry out a comparative cost analysis to produce biodiesel using a free and immobilized lipase. We concluded that the enzyme market, in which lipases play an important role, is extensive, and that immobilized lipases seem to be excellent biocatalysts with feasible costs for industrial applications.

Crystallographic insights into monovalent thallium incorporation: Exploring hydropyrochlore structure for environmental remediation

Abstract Hydropyrochlore, ideally (H2O,)2Nb2(O,OH)6(H2O), is a cubic mineral (space group Fd3m, a = 10.56-10.59 Å, Z = 8) belonging to the pyrochlore supergroup (general formula: A2−mB2X6−wY1−n). The K-rich variety of this species is unique to the Lueshe syenitic-carbonatitic deposit (D.R. Congo), where it occurs as the alteration product of primary (Ca,Na)2Nb2O6F pyrochlores. The structure of this mineral is made of a B2X6 (B = Nb, Ti; X = O, OH) framework that generates tunnels along the [110] direction, where the interstitial sites are partially occupied by water molecules and minor amounts of different cations. These features form the basis for the ion-exchange properties of hydropyrochlore, making it a promising candidate as a mineral sink for heavy metals (e.g., Tl+) dispersed in aqueous matrices, with interesting environmental implications. Tl+ incorporation was induced through imbibition experiments in a diluted Clerici solution using single crystals of hydropyrochlore from Lueshe (D.R. Congo); the modifications induced by Tl+ incorporation were then evaluated through single-crystal X-ray diffraction (SCXRD), electron microprobe analyses (EMPA) and Fourier transform infrared (FT-IR) spectroscopy. After Tl+ imbibition, a dramatic increase of the A-site electron density (n.e− from ~4 to ~60) confirms the entry of a substantial amount of Tl+ at this site (up to about 70%), leading to a lengthening of the A-X distances and the consequent expansion of the unit cell. A decrease of the site scattering at the Y' site (from ~9 to ~4 e−) also occurs, suggesting a loss of aqueous species. Although the predominance of neutral H2O molecules at the interstitial sites of hydropyrochlore from Lueshe is widely accepted by the mineralogical community, our crystal-chemical and FT-IR data provide evidence that the dominant species might be the hydronium ion, with significant implications on the nomenclature of the pyrochlore supergroup. Understanding the crystallographic aspects of hydropyrochlore as a potential waste form for monovalent thallium immobilization not only addresses a pressing environmental concern, but also contributes to the broader field of waste management.

Copper-based metal-organic frameworks (BDC-Cu MOFs) as supporters for α-amylase: Stability, reusability, and antioxidant potential

Copper-based metal-organic frameworks (BDC-Cu MOFs) were synthesized via a casting approach using 1,4-benzene dicarboxylic (BDC) as organic ligand and their properties characterized. The obtained materials were then utilized to immobilize the α-amylase enzyme. The chemical composition and functional components of the synthesized support (BDC-Cu MOFs) were investigated with Fourier transform infrared spectroscopy (FTIR), the surface morphology was determined with scanning electron microscopy (SEM), and the elemental composition was established with energy dispersive X-ray (EDX) analyses. X-ray diffraction (XRD) was employed to analyze the crystallinity of the synthesized DBC-Cu MOFs. The zeta potentials of DBC-Cu MOFs and DBC-Cu MOFs@α-amylase were determined. The immobilized α-amylase demonstrated improved catalytic activity and reusability compared to the free form. Covalent attachment of the α-amylase to BDC-Cu provided an immobilization yield (IY%) of 81% and an activity yield (AY%) of 89%. The immobilized α-amylase showed high catalytic activity and 81% retention even after ten cycles. Storage at 4 °C for eight weeks resulted in a 78% activity retention rate for DBC-Cu MOFs@α-amylase and 49% retention for the free α-amylase. The optimum activity occurred at 60 °C for the immobilized form, whereas the free form showed optimal activity at 50 °C. The free and immobilized α-amylase demonstrated peak catalytic activities at pH 6.0. The maximum reaction velocities (Vmax) values were 0.61 U/mg of protein for free α-amylase and 0.37 U/mg of protein for BDC-Cu MOFs@α-amylase, while the Michaelis‒Menten affinity constants (Km) value was lower for the immobilized form (5.46 mM) than for the free form (11.67 mM). Treatments of maize flour and finger millet samples with free and immobilized α-amylase resulted in increased total phenolic contents. The enhanced antioxidant activities of the treated samples were demonstrated with decreased IC50 values in ABTS and DPPH assays. Overall, immobilization of α-amylase on BDC-Cu MOFs provided improved stability and catalytic activity and enhanced the antioxidant potentials of maize flour and finger millet.

Топическая гиалуронидаза: возможности эффективного применения в дерматологии и косметологии

Hyaluronidase is one of the most popular therapeutic agents in modern dermatology and cosmetology. It is used both by injection and in the form of topical therapy in order to treat various types of scars (hypertrophic, keloid, post-acne, post-burn scars), complications after the injection of fillers based on hyaluronic acid, various diseases accompanied by tissue fibrosis. With the advent of an innovative immobilized form of hyaluronidase for topical use, the possibilities of its use have expanded both in the form of monotherapy and in combined protocols with various methods of physiotherapy. The article provides an overview of the research on the effectiveness and safety of topical hyaluronidase, which is part of Imoferase® cream. The article is of interest to a wide range of specialists (cosmetologists, dermatovenerologists, plastic surgeons, physiotherapists).

A Multicomponent Mannich Reaction Catalyzed by Hydrolases Immobilized on Titanate Nanotubes.

This study presents an innovative method for synthesizing β-amino carbonylated compounds, specifically 2-[phenyl(phenylamino)methyl] cyclohexanone, achieving high conversions and diastereomeric ratios. Using trypsin or α-chymotrypsin in both free and immobilized forms on titanate nanotubes (NtsTi), synthesized through alkaline hydrothermal methods, successful immobilization yields were attained. Notably, α-chymotrypsin, when free, displayed a diastereoselective synthesis of the anti-isomer with 97 % conversion and 16 : 84 (syn : anti) diastereomeric ratio, which slightly decreased upon immobilization on NtsTi. Trypsin, in its free form, exhibited diastereoselective recognition of the syn-isomer, while immobilization on NtsTi (trypsin/NtsTi) led to an inversion of diastereomeric ratio. Both trypsin/NtsTi and α-chymotrypsin/NtsTi demonstrated significant catalytic efficiency over five cycles. In conclusion, NtsTi serves as an effective support for trypsin and α-chymotrypsin immobilization, presenting promising prospects for diastereoselective synthesis and potential industrial applications. Furthermore, it offers promising prospects for the diastereoselective synthesis of 2-[phenyl(phenylamino)methyl] cyclohexanone through multicomponent Mannich reaction and future industrial application.