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In this study, four Brazilian clays (Bofe, Verde-lodo, commercial Fluidgel, and expanded commercial vermiculite) were evaluated for their adsorptive capacity and removal percentage in relation to different toxic metals (Ni2+, Cd2+, Zn2+, and Cu2+). The best results were obtained by expanded vermiculite, with cadmium removal reaching values of 95%. The most promising clay was modified by the sodification process, and the metal cadmium was used to evaluate the ion exchange process. The clays expanded vermiculite (EV) and VNa-sodified vermiculite were evaluated by equilibrium study at 25, 35, and 45 °C. At 25 °C, EV obtained a maximum adsorption capacity of 0.368 mmol/g and sodified vermiculite 0.480 mmol/g, which represents an improvement of 30.4% in modified clay capacity. At 45 °C, the sodified vermiculite reached 0.970 mmol/g adsorption capacity. The Langmuir, Redlich-Peterson Freundlich, and Dubinin-Raduskevich models were adjusted to the results. Langmuir provided the best fit among the models. The thermodynamic quantities (ΔS, ΔH, and ΔG) demonstrated that the process is spontaneous and endothermic and the metal is captured by physisorption and chemisorption in the studied temperature range. For the ion exchange equilibrium, the binary Langmuir and binary Langmuir-Freundlich models were adjusted to the expanded vermiculite and sodified vermiculite isotherms, respectively. Both models were predictive. Thermal analysis indicated good heat resistance even after material modification. The apparent and real densities demonstrated that after each treatment or contamination, the clayey material undergoes contraction in its structure. An improved efficiency of the adsorbent was found after sodification.

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Mefloquine (MQ) is an antimalarial medication prescribed to treat or malaria prevention.. When taken by children, vomiting usually occurs, and new doses of medication frequently need to be taken. So, developing pediatric medicines using taste-masked antimalarial drug complexes is mandatory for the success of mefloquine administration. The hypothesis that binding mefloquine to an ion-exchange resin (R) could circumvent the drug's bitter taste problem was proposed, and solid-state 13C cross-polarization magic angle spinning (CPMAS) NMR was able to follow MQ-R mixtures through chemical shift and relaxation measurements. The nature of MQ-R complex formation could then be determined. Impedimetric electronic tongue equipment also verified the resinate taste-masking efficiency in vitro. Variations in chemical shifts and structure dynamics measured by proton relaxation properties (e.g., T1ρH) were used as probes to follow the extension of mixing and specific interactions that would be present in MQ-R. A significant decrease in T1ρH values was observed for MQ carbons in MQ-R complexes, compared to the ones in MQ (from 100-200 ms in MQ to 20-50 ms in an MQ-R complex). The results evidenced that the cationic resin interacts strongly with mefloquine molecules in the formulation of a 1:1 ratio complex. Thus, 13C CPMAS NMR allowed the confirmation of the presence of a binding between mefloquine and polacrilin in the MQ-R formulation studied.

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This study aimed to produce, characterize and purify a protease from Aspergillus heteromorphus URM0269. After production by solid fermentation of wheat bran performed according to a central composite design, protease was characterized in terms of biochemical, kinetic, and thermodynamic parameters for further purification by chromatography. Proteolytic activity achieved a maximum value of 57.43 U/mL using 7.8 g of wheat bran with 40 % moisture. Protease displayed high stability in the pH and temperature ranges of 5.0-10.0 and 20-30 °C, respectively, and acted optimally at pH 7.0 and 50 °C. The enzyme, characterized as a serine protease, followed Michaelis-Menten kinetics with a maximum reaction rate of 140.0 U/mL and Michaelis constant of 11.6 mg/mL. Thermodynamic activation parameters, namely activation Gibbs free energy (69.79 kJ/mol), enthalpy (5.86 kJ/mol), and entropy (-214.39 J/mol.K) of the hydrolysis reaction, corroborated with kinetic modeling showing high affinity for azocasein. However, thermodynamic parameters suggested a reversible mechanism of unfolding. Purification by chromatography yielded a protease purification factor of 7.2, and SDS-PAGE revealed one protein band with a molecular mass of 14.7 kDa. Circular dichroism demonstrated a secondary structure made up of 45.6 % α-helices. These results show the great potential of this protease for future use in the industrial area.

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A H2-based membrane biofilm reactor (MBfR) was used to remove nitrate from a synthetic ion-exchange brine made up of 23.8 g L-1 NaCl. To aid the selection of the best nitrate management strategy, our research was based on the integrated analysis of ionic exchange and MBfR processes, including a detailed cost analysis. The nitrate removal flux was not affected if key nutrients were present in the feed solution including potassium and sodium bicarbonate. Operating pH was maintained between 7 and 8. By using a H2 pressure of 15 psi, a hydraulic retention time (HRT) of 4 h, and a surface loading rate of 13.6 ± 0.2 g N m-2 d-1, the average nitrate removal flux was 3.3 ± 0.6 g N m-2 d-1. At HRTs of up to 24 h, the system was able to maintain a removal flux of 1.6 ± 0.2 g N m-2 d-1. Microbial diversity analysis showed that the consortium was dominated by the genera Sulfurimonas and Marinobacter. The estimated cost for a 200 m3/h capacity, coupled ion exchange (IX) + MBfR treatment plant is 0.43 USD/m3. This is a sustainable and competitive alternative to an IX-only plant for the same flowrate. The proposed treatment option allows for brine recycling and reduces costs by 55% by avoiding brine disposal expenses.

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The formation and properties of silver and iron nanoscale components in the Ag-Fe bimetallic system deposited on mordenite depend on several parameters during their preparation. Previously, it was shown that an important condition for optimizing nano-center properties in a bimetallic catalyst is to change the order of sequential deposition of components; the order "first Ag+, then Fe2+" was chosen as optimal. In this work, the influence of exact Ag/Fe atomic proportion on the system's physicochemical properties was studied. This ratio has been confirmed to affect the stoichiometry of the reduction-oxidation processes involving Ag+ and Fe2+, as shown by XRD, DR UV-Vis, XPS, and XAFS data, while HRTEM, SBET and TPD-NH3 show little change. However, it was found the correlation between the occurrence and amount of the Fe3+ ions incorporated into the zeolite's framework and the experimentally determined catalytic activities towards the model de-NOx reaction along the series of nanomaterials elucidated in this present paper.

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Titanate nanotubes were synthesized and subjected to an ion exchange reaction with erbium salt aqueous solution to obtain titanate nanotubes exchanged with erbium (3+) ions. In order to evaluate the effects of the thermal treatment atmosphere on the structural and optical properties of erbium titanate nanotubes, we subjected them to heat treatment in air and argon atmospheres. For comparison, titanate nanotubes were also treated in the same conditions. A complete structural and optical characterizations of the samples was performed. The characterizations evidenced the preservation of the morphology with the presence of phases of erbium oxides decorating the surface of the nanotubes. Variations in the dimensions of the samples (diameter and interlamellar space) were promoted by the replacement of Na+ by Er3+ and the thermal treatment in different atmospheres. In addition, the optical properties were investigated by UV-Vis absorption spectroscopy and photoluminescence spectroscopy. The results revealed that the band gap of the samples depends on the variation of diameter and sodium content caused by ion exchange and thermal treatment. Furthermore, the luminescence strongly depended on vacancies, evidenced mainly by the calcined erbium titanate nanotubes in argon atmosphere. The presence of these vacancies was confirmed by the determination of Urbach energy. The results suggest the use of thermal treated erbium titanate nanotubes in argon atmosphere in optoelectronics and photonics applications, such as photoluminescent devices, displays, and lasers.

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Immunological mechanisms of non-IgE-mediated cow's milk protein allergy (CMPA) are not well understood. Such a circumstance requires attention with the aim of discovering new biomarkers that could lead to better diagnostic assays for early treatment. Here, we sought both to investigate the mechanism that underlies non-IgE-mediated CMPA and to identify cow's milk immunoreactive proteins in a Mexican pediatric patient group (n = 34). Hence, we determined the IgE and IgG1-4 subclass antibody levels against cow's milk proteins (CMP) by ELISA. Then, we performed 2D-Immunoblots using as first antibody immunoglobulins in the patients'serum that bound specifically against CMP together with CMP enrichment by ion-exchange chromatography. Immunoreactive proteins were identified by mass spectrometry-based proteomics. The serological test confirmed absence of specific IgE in the CMPA patients but showed significant increase in antigen-specific IgG1. Additionally, we identified 11 proteins that specifically bound to IgG1. We conclude that the detection of specific IgG1 together with an immunoproteomics approach is highly relevant to the understanding of CMPA's physiopathology and as a possible aid in making a prognosis since current evidence indicates IgG1 occurrence as an early signal of potential risk toward development of IgE-mediated food allergy. SIGNIFICANCE: Allergies are one of the most studied topics in the field of public health and novel protein allergens are found each year. Discovery of new principal and regional allergens has remarkable repercussions in precise molecular diagnostics, prognostics, and more specific immunotherapies. In this context, specific IgE is widely known to mediate physiopathology; however, allergies whose mechanism does not involve this immunoglobulin are poorly understood although their incidence has increased. Therefore, accurate diagnosis and adequate treatment are delayed with significant consequences on the health of pediatric patients. The study of type and subtypes of immunoglobulins associated with the immunoreactivity of cow's milk proteins together with an immunoproteomics approach allows better comprehension of physiopathology, brings the opportunity to discover new potential cow's milk protein allergens and may help in prognosis prediction (IgG1 occurrence as an early signal of possible risk toward development of IgE-mediated food allergy).

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Recombinant proteins have revolutionized modern medicine and therapeutics. Currently recombinant proteins are used to treat diseases of great worldwide impact, as they allow maintenance and improvement of the life’s quality of patients with rare genetic diseases, metabolic syndromes, and immunological diseases. Since 1982, after the production of the first therapeutic recombinant protein (PRT), recombinant insulin, all major pharmaceutical companies have tried to develop PRT and supported its growth in the market. The right choice of expression systems and purification processes become essential steps to produce high-quality recombinant proteins with high yield. The recombinant protein Lsa63, the target of this project, is a leptospiral adhesin involved in the bacteria adhesion to the host. Lsa63 is expressed on the surface of patogenic Leptospiras and is absent in saprophytic ones. That said, the use of this protein in the development of new therapies and diagnosis for leptospirosis could be interesting. During this project, Lsa63 was purified from the frozen biomass of E. coli previously produced using liquid chromatography techniques). In all purification steps Lsa63 was quantified by BCA (bicinchoninic acid) and analyzed by SDS-PAGE electrophoresis and Western Blotting. The relative purity of Lsa63 was estimated by densitometry of SDS-PAGE bands. Immobilized-metal affinity chromatography (IMAC) was chosen as the first purification step and 24.4% of Lsa63 was yield with relative purity of 54.8%, followed by size-exclusion chromatography (SEC) with recovery of 95.2% and last step ion-exchange chromatography (IEC) with 7.9% and 80.3% of relative purity. Despite having obtained 80.3% of relative purity the global yield was low (7.9%).

As proteínas recombinantes revolucionaram a medicina moderna e a terapêutica. Por isso, atualmente, as proteínas recombinantes são utilizadas para tratamento de doenças de grande impacto mundial, pois permitem manutenção e melhoria da qualidade de vida de pacientes portadores de doenças genéticas raras, síndromes metabólicas e doenças imunológicas. Desde 1982, após a produção da primeira proteína recombinante terapêutica (PRT), insulina recombinante, todas as grandes farmacêuticas começaram a desenvolver PRT e impulsionaram o crescimento destas no mercado. A escolha correta dos sistemas de expressão e processos de purificação tornam-se etapas essenciais para produção de proteínas recombinantes de alta qualidade e em alto rendimento. A proteína recombinante Lsa63, alvo deste projeto, é uma adesina de leptospira envolvida na adesão da bactéria no organismo dos hospedeiros. A Lsa63 é expressa na superfície de Leptospiras patogênicas e apresenta-se ausente em cepas saprofíticas. Dito isto, a utilização desta proteína, no desenvolvimento de novas terapias e diagnóstico para leptospirose pode ser interessante. Durante o decorrer deste projeto, a Lsa63 foi purificada a partir da biomassa congelada de E. coli utilizando técnicas de cromatografia líquida. Em todas as etapas de purificação a Lsa63 foi quantificada por BCA (ácido bicinchonínico) e analisada por eletroforese SDS-PAGE e Western Blotting. A pureza relativa da Lsa63 foi estimada por densitometria das bandas do gel de eletroforese. A cromatografia de afinidade por íons metálicos imobilizados (IMAC) foi escolhida como primeira etapa de purificação sendo que a Lsa63 foi obtida com rendimento de 24,4% e pureza relativa de 54,8%, seguida pela cromatografia de exclusão molecular com recuperação de 95,2% e a última etapa a cromatografia de troca iônica com recuperação de 52,0% e pureza relativa de 80,3%. Apesar de ter obtido uma pureza relativa de 80,3% a recuperação global incluindo todas as etapas cromatográficas foi baixa sendo 7,9%.

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Lolium multiflorum grass is the major pollen allergen source in the southern region of Brazil, but most of its allergens remain poorly characterized. The aim of this study was to investigate antibody reactivity to L. multiflorum crude and carboxymethyl-ligand extracts in allergic patients and healthy individuals. Ion exchange carboxymethyl (CM) chromatography (CM-Sepharose) was used to isolate proteins (S2) from L. multiflorum crude extract (S1), which were assessed by SDS-PAGE. S1- and S2-specific IgE and IgG4 levels were measured by ELISA using sera from 55 atopic and 16 non-atopic subjects. Reactive polypeptide bands in S1 and S2 were detected by immunoblotting, and the most prominent bands in S2 were analyzed by mass spectrometry (MS-MS). Similar IgE and IgG4 levels were observed to both S1 (IgE median absorbance: 1.22; IgG4 median absorbance: 0.68) and S2 (IgE median absorbance: 1.26; IgG4 median absorbance: 0.85) in atopic subjects. S1 and S2 had positive correlations for IgE and IgG4 (IgE: r=0.9567; IgG4: r=0.9229; P<0.0001) levels. Homology between S1 and S2 was confirmed by IgE (84%) and IgG4 (83%) inhibition. Immunoblotting revealed that the 29-32 kDa band was recognized by 100% of atopic subjects in both S1 and S2. MS-MS analysis identified similarity profile to groups 1 and 5 grass allergens. This study revealed that carboxymethyl-ligand fraction played an important role for pollen allergy diagnosis by containing clinically relevant allergens and constituted a promising candidate for allergen-specific immunotherapy.

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Contemporary industrial processes and the application of new technologies have increased the demand for rare earth elements (REEs). REEs are critical components for many applications related to semiconductors, luminescent molecules, catalysts, batteries, and so forth. REEs refer to a group of 17 elements that have similar chemical properties. REE mining has increased considerably in the last decade and is starting an REE supply crisis. Recently, the viability of secondary REE sources, such as mining wastewaters and acid mine drainage (AMD), has been considered. A strategy to recover REEs from secondary water-related sources is through the usage of adsorbents and ion exchange materials in preconcentration steps due to their presence in low concentrations. In the search for more sustainable processes, the evaluation of synthetic polymers and natural source materials, such as cellulose-based materials, for REE capture from secondary sources should be considered. In this review, the chemistry, sources, extraction, uses, and environmental impact of REEs are briefly described to finally focus on the study of different adsorption/ion exchange materials and their performance in capturing REEs from water sources, moving from commercially available ion exchange resins to cellulose-based materials.

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Genome editing using the CRISPR/Cas9 system is one of the trendiest methodologies in the scientific community. Many genome editing approaches require recombinant Streptococcus pyogenes Cas9 (SpCas9) at some point during their application, for instance, for in vitro validation of single guide RNAs (SgRNAs) or for the DNA-free editing of genes of interest. Hereby, we provide a simple and detailed expression and purification protocol for SpCas9 as a protein fused to GFP and MBP. This protocol improves protein yield and simplifies the purification process by overcoming the frequently occurring obstacles such as plasmid loss, inconsistent protein expression levels, or inadequate protein binding to affinity resins. On average, this protocol yields 10 to 30 mg of purified, active, His6−MBP−SpCas9 NLS−GFP protein. The purity addressed through SDS-PAGE is > 80%.

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Phytate is the main form of phosphorus in corn ethanol coproducts and poses digestion issues in monogastric-animal feed. Extracting phytate as a commodity chemical will bring extra revenue to the corn ethanol industry and reduces potential phosphorus pollution from livestock waste management. We assessed a simplified scale-up approach of an ion-exchange separation system applied to extract phytate from thin stillage using volumetric parameters and simplifications of the van Deemter model. Thin stillage is one of the main byproducts generated on dry-grind corn-to-ethanol plants and accounts for the liquid portion of the bottom product generated in the ethanol distillation process. Thin stillage is rich in dissolved phytate, which served as the basis for an ion-exchange extraction system developed with a scalability factor of 50. Under the evaluated conditions, similar breakthrough profiles were obtained when similar Péclet and Stanton numbers were maintained for the scales studied, demonstrating that a simple and straightforward scale-up can be attained if special attention is given to maintaining both parameters as the basis of calculations of the plate numbers of ion-exchange columns.

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In this study, chloroquine resinates were prepared at a 1:1 (w:w) drug-to-resin ratio using the batch method with polacrilex (PC), sodium polystyrene sulfonate (SPS), and polacrilin potassium (PP) ion exchange resins (IER). The influence of drug/resin ratio and pH of the medium on drug loading efficiency was explored. UV-VIS spectrophotometric analysis showed that SPS resin had high loading efficiency for chloroquine diphosphate (CLP), above 89%, regardless of the pH. PP resin was more effective at pH 5.0 (90.68%) than at pH 1.0 (2.09%), and PC resin had only 27.63% of CLP loading efficiency. CLP complexation with IER yielded amorphous mixtures according to results from differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD), thus indicating drug-resin interaction. The taste masking efficiency was evaluated with in vitro methods using an adapted dissolution test and an electronic tongue system. During dissolution tests, SPS released only 1.0% of CLP after 300 s, while PP released over 10% after 90 s in simulated saliva solution. The electronic tongue distinguished the samples containing CLP, resins, and resinates by using multidimensional projection techniques that indicated an effective drug taste masking. In an accelerated stability study, the drug contents did not decrease in chloroquine resinates, and there was no physical degradation of the resinates after 60 days. Using chloroquine resinates therefore represents a novel way to evaluate taste masking in vitro which is relevant for the early formulation development process.

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The use of mineral clays as alternative adsorbent has received attention due to their physicochemical characteristics, superficial negative charge, abundance of vermiculite (especially in Brazil), low cost, and chemical composition, which allows the material modification to increase the adsorptive capacity. This manuscript evaluated the use of expanded vermiculite (EV) and sodium-modified vermiculite (VNa) in the adsorption and ion exchange of Cd2+ ions. The sodification was successfully carried out making the ion exchange capacity greater in the modified clay, confirmed by EDX, cation exchange capacity (CEC), DRX, and FTIR analysis. The CEC was 210 and 233 mEq/100 g for the EV and VNa, respectively, with 97.8% exchangeable ion (Na+) in the VNa. FTIR spectra showed small variations in the groups related to ion exchange and XRD analysis indicated changes in the distance of the layers with loss of crystallinity after clay modification, which was recovered after cadmium adsorption. The kinetics became faster with an equilibrium time of 10 min for VNa and 45 min for EV. Cd2+ removal by vermiculite above 99% was achieved. Pseudo-second order model best described the kinetics, in which the resistance to mass transfer in external film is the limiting step of the process and, once this resistance is overcome, the ion exchange happens quickly. Despite the decrease in surface area after sodification, the adsorptive capacity increased 158% in the sodified adsorbent, from 0.107 mmol/g for EV to 0.276 mmol/g for VNa, under the evaluated conditions.

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Sulfate polysaccharides with unique structures of the chondroitin/dermatan and heparin/heparan families of sulfated glycosaminoglycans have been described in several species of ascidians (Chordata-Tunicata). These unique sulfated glycans have been isolated from the ascidians and characterized by biochemical and spectroscopic methods. The ascidian glycans can be extracted by different tissues or cells by proteolytic digestion followed by cetylpyridinium chloride/ethanol precipitation. The total glycans are then fractionated by ion-exchange chromatography on DEAE-cellulose and/or Mono Q (HR 5/5) columns. Alternatively, precipitation with different ethanol concentrations can be employed. An initial analysis of the purified ascidian glycans is carried out by agarose gel electrophoresis on diaminopropane/acetate buffer, before or after digestion with specific glycosaminoglycan lyases or deaminative cleavage with nitrous acid. The disaccharides formed by exhaustive degradation of the glycans are purified by gel-filtration chromatography on a Superdex Peptide column and analyzed by HPLC on a strong ion-exchange Sax Spherisorb column. 1H- or 13C-nuclear magnetic resonance spectroscopy in one or two dimensions is used to confirm the structure of the intact glycans.

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Even at low concentrations in environmental waters, some viruses are highly infective, making them a threat to human health. They are the leading cause of waterborne enteric diseases. In agriculture, plant viruses in irrigation and runoff water threat the crops. The low concentrations pose a challenge to early contamination detection. Thus, concentrating the virus particles into a small volume may be mandatory to achieve reliable detection in molecular techniques. This paper reviews the organic monoliths developments and their applications to concentrate virus particles from waters (waste, surface, tap, sea, and irrigation waters). Free-radical polymerization and polyaddition reactions are the most common strategies to prepare the monoliths currently used for virus concentration. Here, the routes for preparing and functionalizing both methacrylate and epoxy-based monoliths will be shortly described, following a revision of their retention mechanisms and applications in the concentration of enteric and plant viruses in several kinds of waters.

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This study analyzed the thermostability and effect of calcium ions on the enzymatic activity of α-amylase produced by Bacillus licheniformis strain LB04 isolated from Espinazo Hot springs in Nuevo Leon, Mexico. The enzyme was immobilized by entrapment on agar-agarose beads, with an entrapment yield of 19.9%. The identification of the bacteria was carried out using 16s rDNA sequencing. The enzyme was purified through ion exchange chromatography (IEX) in a DEAE-Sephadex column, revealing a protein with a molecular weight of ≈130 kDa. The enzyme was stable at pH 3.0 and heat stable up to 80 °C. However, the optimum conditions were reached at 65 °C and pH 3.0, with a specific activity of 1851.7 U mg-1 ± 1.3. The agar-agarose immobilized α-amylase had a hydrolytic activity nearly 25% higher when compared to the free enzyme. This study provides critical information for the understanding of the enzymatic profile of B. licheniformis strain LB04 and the potential application of the microorganisms at an industrial level, specifically in the food industry.

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Water for human consumption is the main source of fluoride exposure. The concentration in water should not exceed 1 mg/L of fluoride since, at higher levels; it increases the risk of dental fluorosis, among other adverse effects. The fluoride content of 149 water samples from different aqueducts in Cauca (Colombia) has been determined by ion exchange chromatography with the aim of fluoride risk assessment. The rural area of the Municipality of Santander de Quilichao registered fluoride concentrations between 0.012 and 0.150 mg/L. The urban area of Santander de Quilichao recorded lower fluoride levels than the rural area (0.027-0.068 mg/L). The urban area of the Municipality of Cajibío registered fluoride levels of 0.082-0.186 mg/L. The highest levels of fluoride were found in Timbío (0.121-0.210 mg/L). The fluoride levels recorded in this study are not considered sufficient to trigger dental fluorosis. Likewise, optimal levels are not considered to protect the child population against dental caries. However, a monitoring plan of fluoride concentrations in water should be implemented to assure the quality and safe of the water.

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Fluoride can cause some diseases to humans when ingested in large quantities and for a long time. Due to this, it is necessary to remove or reduce the amount of fluoride in effluents before release into the water bodies. This work aimed to evaluate the ability of hydrocalumites synthesized by two different methodologies and calcined hydrocalumite in reducing the content of fluoride in aqueous solutions. The materials were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), N2 physisorption, thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The removal capacity of fluoride ions ranged from 14.9 to 189.6 mg F- g-1. The removal mechanisms by hydrocalumites were ion exchange and adsorption at low concentrations, while at high concentrations were adsorption and precipitation of calcium fluoride. In relation to the use of calcined hydrocalumite, the removal mechanisms were ion exchange and reconstruction of structure (memory effect) in low concentrations. By the adsorption tests, it was observed that the results fit better the Langmuir isotherm model.

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This work characterizes and comparatively assess two cation exchange membranes (PSEBS SU22 and CF22 R14) and one bipolar membrane (FBM) in microbial electrolysis cells (MEC), fed either by acetate or the mixture of volatile fatty acids as substrates. The PSEBS SU22 is a new, patent-pending material, while the CF22 R14 and FBM are developmental and commercialized products. Based on the various MEC performance measures, membranes were ranked by the EXPROM-2 method to reveal which of the polymeric membranes could be more beneficial from a complex, H2 production efficiency viewpoint. It turned out that the substrate-type influenced the application potential of the membranes. Still, in total, the PSEBS SU22 was found competitive with the other alternative materials. The evaluation of MEC was also supported by analyzing anodic biofilms following electroactive bacteria's development over time.

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