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Lung injuries are increasingly prevalent due to various diseases causing alveolar damage, potentially leading to respiratory disorders. This study employed an incubation method to develop nano-encapsulated ibuprofen within a chitosan matrix for targeted pulmonary therapy. The encapsulation was successful without altering the molecular structure of chitosan, and a 500 mg dose was identified as optimal through lung tissue cell viability and histological analysis. The controlled release mechanism of this formulation ensures targeted delivery to the lungs, reducing inflammation and promoting alveolar regeneration. This approach highlights the importance of dose optimization and presents a promising strategy to enhance the efficacy and safety of pulmonary treatments. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work is the evaluation of two bimetallic materials, PdNiO and NiAl‐layered double hydroxides (NiAl‐LDHs) for their prospective use in Lab‐on‐a‐Chip devices, in which urea contained in human urine is used as fuel to provide the energy required by the device and dopamine in the sample is detected. A urea microfluidic fuel cell, using human urine as fuel and NiAl‐LDHs and PdNiO as anodes, was constructed and evaluated, resulting in a cell potential of 1 V with 50.19 mW/cm2 power density for NiAl‐LDHs and 0.9 V and 32.94 mW/cm2 for PdNiO. The multifunctionality of these anodes was extended for detecting dopamine with detection limits of 7.38×10−8 M and 5.46×10−6 M for NiAl‐LDHs and PdNiO, respectively. The higher content of hydroxides on NiAl‐LDHs than PdNiO material allowed a better activity for urea oxidation and dopamine detection. These results show the prospects for self‐powered biomedical Lab‐on‐a‐Chip device development. [ABSTRACT FROM AUTHOR]

Crystallization processes are extremely important in pharmaceutical science since they affect both the solid-state properties of the drug substances, and the drug product stability and performance. The crystallization stage must guarantee the quality of the product by assuring high purity, desired particle size distribution and crystalline morphology. This paper presents the use of artificial neural networks (ANNs) in combination with genetic algorithms (GAs) to model the complex process and identify the main parameters to optimize the crystallization of a specific pharmaceutical product in order to achieve substantial improvement in the quality of the product. Temperature, water content, volume, concentration and time addition of solvents, pH, and stirring speed were defined as inputs to build the ANN model to predict the crystal density. The ANN was able to learn the nonlinear relationships between structural information of the crystal and the main parameters of the process from an experimental set; the maximum mean absolute percentage error for the predicted values was 7.22%. The GA provided an optimal solution to define the operational conditions to take from a crystal density value of 0.61 to 0.737 g cm − 3 which represents a significant improvement in the physical and crystallographic properties. Experimental evaluations were carried out directly in the production plant obtaining crystal density values near the predicted one. [ABSTRACT FROM AUTHOR]

• Successful covalent immobilization of MAO-A enzyme on multi-walled carbon nanotubes. • Improvement of pH, thermal stability and kinetics of immobilized MAO-A enzyme. • Improved operational and storage stability of immobilized MAO-A enzyme. • The biocomposite exhibited a low detection limit for serotonin: 2 × 10−7 M. Serotonin is a potential biomarker for diverse neuropsychiatric and neurodevelopmental disorders. In this study a novel biocomposite based on the enzyme monoamine oxidase-A (MAO-A) immobilized by covalent binding on multi-walled carbon nanotubes (MWCNT) has been developed for detection of serotonin. Immobilized MAO-A (MWCNT/MAO-A) retained 94.3% of its catalytic activity, showing good thermal and pH stability at temperatures from 35 to 40 °C and pH from 7–8.5. A decrease of the apparent Michaelis-Menten constant was observed compared to free MAO-A indicating an improvement of its affinity towards its substrate. Evaluation of MWCNT/MAO-A by scanning electrochemical microscopy (SECM) demonstrated that the immobilized enzyme maintains its activity. The biocomposite was employed for successfull detection of serotonin through quantification of the enzymatically produced hydrogen peroxide (H 2 O 2). A MWCNT/MAOA modified glassy carbon electrode (GCE) was characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Electrochemical measurements were performed in simulated body fluid (SBF), obtaining a linear response of 5.67 × 10-7 M - 2.26 × 10-6 M, with a low detection limit of 2 × 10-7 M (35.6 ng mL-1;S/N = 3) and a quantification limit of 6.73 × 10-7 M (118.7 ng mL-1;S/N = 3); values that are in range with serotonin levels found in different neurological disorders. The biocomposite have the potential to be employed in future development of biosensing devices for serotonin detection. [ABSTRACT FROM AUTHOR]

In this study, the biosynthesis of polyhydroxyalkanoates (PHAs) was carried out using Pseudomonas putida and Pseudomonas aeruginosa . These PHAs were produced using reagent-grade glycerol and crude glycerol as the carbon sources. The objective was to compare the production of PHAs and to functionalize these polymers with silver nanoparticles to provide antibacterial properties for potential biomedical applications. The findings from the physical and chemical analyses confirmed the successful synthesis and extraction of PHAs, achieving comparable yields using both crude glycerol and reagent-grade glycerol as carbon sources across both strains. Approximately 16% higher PHAs production was obtained using Pseudomonas putida compared to Pseudomonas aeruginosa , and no significant difference was observed in the production rate of PHAs between the two carbon sources used, which means that crude glycerol could be utilized even though it has more impurities. Notably, PHAs functionalized with silver nanoparticles showed improved antibacterial effectiveness, especially those derived from reagent-grade glycerol and the Pseudomonas aeruginosa strain.

This paper presents two immobilization methods for the intracellular invertase (INVA), from Zymomonas mobilis. In the first method, a chimeric protein containing the invertase INVA, fused through its C-terminus to CBDCex from Cellulomonas fimi was expressed in Escherichia coli strain BL21 (DE3). INVA was purified and immobilized on crystalline cellulose (Avicel) by means of affinity, in a single step. No changes were detected in optimal pH and temperature when INVA-CBD was immobilized on Avicel, where values of 5.5 and 30 degrees C, respectively, were registered. The kinetic parameters of the INVA-CBD fusion protein were determined in both its free form and when immobilized on Avicel. Km and Vmax were affected with immobilization, since both showed an increase of up to threefold. Additionally, we found that subsequent to immobilization, the INVA-CBD fusion protein was 39% more susceptible to substrate inhibition than INVA-CBD in its free form. The second method of immobilization was achieved by the expression of a 6xHis-tagged invertase purified on Ni-NTA resin, which was then immobilized on Nylon-6 by covalent binding. An optimal pH of 5.5 and a temperature of 30 degrees C were maintained, subsequent to immobilization on Nylon-6 as well as with immobilization on crystalline cellulose. The kinetic parameters relating to Vmax increased up to 5.7-fold, following immobilization, whereas Km increased up to 1.7-fold. The two methods were compared showing that when invertase was immobilized on Nylon-6, its activity was 1.9 times that when immobilized on cellulose for substrate concentrations ranging from 30 to 390 mM of sucrose.

The recombinant invertase INVB (re-INVB) from Zymomonas mobilis was immobilized on microbeads of Nylon-6, by means of covalent bonding. The enzyme was strongly and successfully bound to the support. The activity of the free and immobilized enzyme was determined, using 10% (w/v) sucrose, at a temperature ranging between 15 and 60 degrees C and a pH ranging between 3.5 and 7. The optimal pH and temperature for the immobilized enzyme were 5.5 and 25 degrees C, respectively. Immobilization of re-INVB on Nylon-6 showed no significant change in the optimal pH, but a difference in the optimal temperature was evident, as that for the free enzyme was shown to be 40 degrees C. The values for kinetic parameters were determined as: 984 and 98 mM for Kappm of immobilized and free re-INVB, respectively. Kappcat values for immobilized and free enzymes were 6.1x10(2) and 1.2x10(4) s(-1), respectively, and immobilized re-INVB showed Vappmax of 158.73 micromol h min(-1) mg(-1). Immobilization of re-INVB on Nylon-6 enhanced the thermostability of the enzyme by 50% at 30 degrees C and 70% at 40 degrees C, when compared to the free enzyme. The immobilization system reported here may have future biotechnological applications, owing to the simplicity of the immobilization technique, the strong binding of re-INVB to the support and the effective thermostability of the enzyme.

The recombinant invertase (re-INVB) from Zymomonas mobilis was immobilized by adsorption onto the totally cinnamoylated derivative of D-sorbitol. The polymerization and cross-linking of the derivative initially obtained was achieved by irradiation in the ultraviolet region, where this prepolymer shows maximum sensitivity. Immobilization of re-INVB on this support involves a process of physical adsorption and intense hydrophobic interactions between the cinnamoyl groups of the support and related groups of the enzyme. Enzyme concentration, immobilization time, and irradiation time were important parameters affecting the immobilization efficiency. The optimum reaction pH of immobilized enzyme was 5, and the optimal reaction temperature was 40 degrees C. The apparent Michaelis constant and the apparent catalytic constant of re-INVB immobilized on the SOTCN derivative acting on sucrose was 78+/-5 mM and 5x10(4)+/-3x10(2) s(-1), respectively, while for the free enzyme, it was 98.0+/-4 mM and 1.2x10(4)+/-2.5x10(2) s(-1), respectively, suggesting a better apparent affinity of the enzyme for the substrate and a better hydrolysis rate when immobilized than when in solution. Immobilized re-INVB also showed good thermal stability and good operational stability (40% of the initial activity remaining after 45 cyles of 1 min duration and 90.6 mg of sucrose being hydrolyzed in 45 min per 2.5 mg of immobilized protein). The results showed that cinnamic carbohydrate esters of D-sorbitol are an appropriate support for re-INVB immobilization and the production of invert sugar.