Concentrated Dispersions Research Articles

Fine tuning enzyme activity assays for monitoring the enzymatic hydrolysis of PET

Efficient monitoring of the enzymatic PET-hydrolysis is crucial for developing novel plastic-degrading biocatalysts. Herein, we aimed to upgrade in terms of accuracy the analytical methods useful for monitoring enzymatic PET-degradation. For the HPLC-based assessment, the incorporation of an internal standard within the analytic procedure enabled a more accurate quantification of the overall TPA content and the assessment of molar distributions and relative content of each aromatic degradation product. The provided calibration curves cover a broad concentration range, from µM to low mM scale, facilitating assessment of both lower and higher PETase activities, with a limit of detection positioned below the reported PET-degrading activities. The increased reproducibility and accuracy of the improved HPLC method, compared to the previous methods, was supported by lower dispersion of product concentrations and their lower deviation from theoretical values over multiple measurements. The other predominantly employed UV-spectroscopy assay was also improved in terms of employed wavelength and medium extinction coefficient of the three aromatic degradation products, while being cross-validated by the improved HPLC method. Finally, both methods were used for monitoring the product formation within the leaf-branch compost cutinase (LCC)-mediated PET-hydrolysis and provided individual time-productivity profiles for each aromatic degradation product.

Biocompatible 2D Material Inks Enabled by Supramolecular Chemistry: From Synthesis to Applications.

ConspectusThe emergence of two-dimensional (2D) materials, such as graphene, transition-metal dichalcogenides (TMDs), and hexagonal boron nitride (h-BN), has sparked significant interest due to their unique physicochemical, optical, electrical, and mechanical properties. Furthermore, their atomically thin nature enables mechanical flexibility, high sensitivity, and simple integration onto flexible substrates, such as paper and plastic.The surface chemistry of a nanomaterial determines many of its properties, such as its chemical and catalytic activity. The electronic properties can also be modified by surface chemistry through changes in charge transfer or by the presence of surface states. Surface defects and functional groups can act as trap sites for excitons, hence affecting the optical properties. Furthermore, surface chemistry determines the stability and dispersibility of nanomaterials in colloidal dispersions as well as their biocompatibility and toxicity. In addition, the surface chemistry dictates how nanomaterials interact with biological systems, influencing cellular uptake, immune response, and biodistribution, to name a few examples. It is, therefore, crucial to be able to produce 2D materials with tunable surface chemistry to match target applications.Because of their dimensionality, 2D materials can be easily functionalized with noncovalent and covalent approaches. This review delves into the role of supramolecular chemistry, which is based on noncovalent interactions, in achieving stable and highly concentrated water-based dispersions of 2D materials with specific surface chemistry.In particular, we provide an overview of the recent progress made by our group in the field of solution-processed 2D materials produced by liquid-phase exfoliation with pyrene derivatives used as supramolecular receptors. We highlight the relationship between the structure of the pyrene derivative stabilizer and the concentration, stability, and lateral size and thickness distributions of the produced nanosheets. Subsequently, we give a short overview of the applications enabled by the supramolecular approach in printed electronics, sensing, bioelectronics, and in the biomedical field. We show that the careful design of the pyrene derivative enables us to achieve excellent stability of the material in the cellular medium, which is essential to accurately assess biological effects. We also highlight seminal case studies on the use of cationic graphene in the therapeutics of lysosomal storage disorders, and on the use of TMD nanosheets for trained immunity and as immune-compatible nanoplatforms, traceable at the single-cell and tissue (suborgan) levels.This Account aims to provide a comprehensive guide for readers on the potential of the supramolecular approach for the design of 2D material dispersions with tailored surface chemistry. This approach is expected to be extremely attractive for many applications, from tissue engineering to energy storage devices, so we hope that this Account will drive further efforts and advancements in this field by ultimately leading to the integration of solution-processed 2D materials made by supramolecular chemistry into practical applications.

Freeze-thaw synergistic salt template prepared self-supporting MXene/wood-derived porous carbon electrode for supercapacitors

Supercapacitors are anticipated to be utilized in the upcoming generation of emerging energy storage devices. The electrode stands out as the most crucial component of the supercapacitor, and a bulk electrode containing sufficient electrochemically active substances is beneficial for enhancing the energy density of the energy storage device. Furthermore, the pore structure and wettability regulation of the electrode are pivotal factors that determine its electrochemical performance. In this study, we propose a monolithic electrode which was created by impregnating different concentrations of MXene dispersions into wood-based carbon materials co-treated with freeze-thaw/LiCl salt template, assisted by freezing treatment. The integration of MXene and freeze-thaw/LiCl salt template wood results in a layered porous structure that enhances both wettability and conductivity of the electrode. Freeze-thaw/LiCl salt template carbonized wood@MXene-4 (FCW@MXene-4) demonstrates an impressive electrochemical performance reaching 7.7 F cm−2 (184.5 F g−1) at a current density of 1 mA cm−2. Additionally, when assembled into a symmetric supercapacitor (SSC), it exhibits high specific capacitance at 3.4 F cm−2 (34.1 F g−1/17 F cm−3) and high energy density at 0.478 mWh cm−2 (6 Wh kg−1/2.39 mWh cm−3) at 1 mA cm−2, with a capacity retention rate of 88 % after 10,000 cycles. This research introduces an innovative self-supporting thick electrode design strategy for high-performance energy storage devices.

In Situ Raman Spectroscopy-Enabled Microfluidic Gel Chromatography for Revealing Real-Time Separation Dynamics of Single-Walled Carbon Nanotubes.

Single-walled carbon nanotubes (SWNTs) exhibit distinct electronic properties, categorized as metallic or semiconducting, determined by their chirality. The precise and selective separation of these electronic types is pivotal for advancing nanotechnology applications. While conventional gel chromatography has been widely employed for large-scale separations, its limitations in addressing microscale dynamics and electronic-type differentiation have persisted. Here, we present a polydimethylsiloxane (PDMS)-based microfluidic gel chromatography platform, coupled with real-time in situ Raman spectroscopy, designed to achieve the high-resolution electronic-type separation of SWNTs. This platform systematically isolates metallic- and semiconducting-enriched fractions (M1-M3 and S1-S3) while quantitatively analyzing separation dynamics through G-band spectral shifts and G-/G+ intensity ratios. By normalizing the SDS concentration and calculating rate constants, we reveal the intrinsic elution kinetics of SWNTs, with metallic fractions exhibiting faster elution dynamics compared to their semiconducting counterparts. Our approach bridges the gap between microscale precision and industrial scalability, emphasizing the critical role of dispersant concentration in fine-tuning separation outcomes. This advancement not only resolves the challenges of electronic-type differentiation but also demonstrates the versatility of PDMS microfluidic systems in delivering real-time insights into nanomaterial purification processes. By integrating continuous dynamic analysis with gel chromatography, this study establishes a transformative framework for scaling nanomaterial separations and unlocking new potential in chirality-specific applications.

Rheology and structure of ceramic stereolithography slurries: Role of powder nature, dispersant, and orthogonal strain

AbstractWe investigate the rheological properties of ceramic slurries designed for laser stereolithography manufacturing in relation to their formulation, including the powder morphology, their volume fraction, and the concentration of dispersing agent. By combining dynamic strain sweep and Small‐Angle X‐ray Scattering (SAXS) experiments, we first illustrate that slurry viscosity follows an exponential trend with increasing particles content, with steeper increase observed for more aggregated particles. We then show that increasing the dispersant concentration up to an optimal value decreases slurry viscosity, as SAXS measurements reveal a reduction and homogenization in agglomerate size. Finally, we evidence that applying vertical oscillatory deformation during steady shear flow induces fluidization of the slurry. The shear viscosity exhibits a time–strain rate equivalence, enabling the generalization of this effect across a wide range of formulations. This methodology holds potential for industrial applications, where introducing vibration perpendicular to the scraping blade motion could improve the surface quality of the spread slurry prior to polymerization.

Application the Mike 3 model to simulate the turtibity dispersion due to sediment dumping activities in Nghi Son Port, Thanh Hoa Province

The study applied the Mike 3 hydrodynamic model to simulate the turbidity propagation from sediment mud deposition activities at sea in the Nghi Son port area, Thanh Hoa province. The research results show that during the northeast monsoon period, the sediment mud concentration field is distributed southward from the deposition area, with sediment mud concentrations ranging from 0.01 kg/m³ to 0.4 kg/m³ within an influence radius of approximately 2.5 km. During the southwest monsoon period, the turbidity concentration distribution expands northward from the deposition area due to the influence of wind and currents during this season. The northern area of Nghi Son port is affected by the dispersion of turbidity concentrations below 0.04 kg/m³. The area surrounding Hon Me island has sediment mud concentrations ranging from 0.015 kg/m³ to 0.025 kg/m³. The turbidity concentration distribution with depth ranges from 0.01 kg/m³ to 0.4 kg/m³ and is primarily located at the seafloor depths ranging from -14 m to -18 m. The turbidity concentration gradually decreases towards the water surface. The turbidity concentration in the upper water layer is relatively low, ranging from 0.01 kg/m³ to 0.08 kg/m³, with depths from 0 to -5 m.

Optical properties of nanoparticles in blood: considering blood absorption

Nanomedicine is emerging as a crucial avenue for exploring new therapeutic and diagnostic techniques in the medical field. Effective monitoring of the dispersion concentration of nanoparticles using optical methods is an extremely important topic in this area. However, existing research has not recognized that the light absorption of blood can lead to significant errors in related optical measurements. This paper, considering the absorption properties of the background medium, meticulously discusses the variations in the single-scattering characteristics of nanoparticles in plasma and whole blood, and analyzes the influence of parameters such as incident wavelength, particle size, refractive index, and background medium refractive index. The results indicate that neglecting the light absorption of the background medium may lead to differences of up to approximately 50% in the results, but this is also influenced by parameters such as incident wavelength, particle size, and refractive index. Furthermore, there are still significant differences in the variations of the single-scattering properties of nanoparticles with identical characteristics in plasma and whole blood. These results indicate the importance of in-depth research into calibration techniques for optical instruments in monitoring nanoparticles in the blood, and further enhance the development of nanoparticle monitoring technology in nanomedicine.

Impact of stochastic collisions on cloud droplet number concentration and relative dispersion during Meiyu frontal system

Impact of stochastic collisions on cloud droplet number concentration and relative dispersion during Meiyu frontal system

Validating ex210Pb sediment dating methods applied to a large anthropogenically-impacted river basin

Sediment dynamics in five sites within the Mobile River Basin, Alabama, impacted by (i) dam-and-lock use, (ii) urbanization, (iii) industrial/mining practices, (iv) flooding, and (v) storm surge events were evaluated to understand better anthropogenic impacts on regional sediment budgets. Three widely used sediment dating models based on excess 210Pb (ex210Pb) (i.e., Constant Rate of Supply, CRS, Constant Initial Concentration, CIC, and Advective Dispersion Equation, ADE) and two recently developed ones (i.e., Porosity Variation, PV and Porosity Variation Without Diffusion, PVWD) were tested to determine their applicability to these anthropogenically altered lacustrine and coastal areas. To verify results from ex210Pb models, we used conventional time markers, including regional hydrograph records and historical aerial images. We found that the traditional time-marker 137Cs is no longer helpful due to its current low inventories in the sediments. Drainage-to-lake area ratios were used to determine relative runoff and atmospheric radionuclide contributions. Statistical analysis of physical properties such as porosity, bulk and dry density, water content, and sediment geochemical compositions were utilized to support sediment transport and site development hypotheses. When constructing the sediment history at each site using these proxies, we found that the conventional CIC and ADE models produced unreliable ages because of violation of requirements for exponentially decreasing porosity and ex210Pb activity with depth. We found that two new models, PV and PVWD, that account for heterogeneous porosity, produced more reliable sediment ages. These two models produced ages with lower uncertainties than the CRS model, outperforming the other conventional models tested. We conclude that the PV and PVWD models are more appropriate for environments experiencing erosional and abrupt depositional events, which in our study resulted from dam construction and storm-surge events. Model sensitivity analysis showed that decreasing average particle density produces younger sediment ages by the PV and PVWD models. Higher ex210Pb activity analytical uncertainty resulted in lower sedimentation rates and higher estimated ages by all five models.

Migration and catalytic viscosity reduction of biochar-based catalyst fluid in heavy oil reservoir pores

The method for reducing heavy oil viscosity through catalysts has remained experimental. Catalyst aggregation in reservoirs is a challenging issue. This study prepares catalyst fluids with both hydrophilic and oleophilic properties and uses dispersants to inhibit aggregation. Stability is assessed using direct observation and an ultraviolet-visible spectrophotometer, with results showing that a dispersant concentration of 0.05 wt. % stabilizes catalyst fluids. Micromodel experiments are conducted to investigate the catalytic performance and dispersion characteristics of catalyst fluids under various conditions. A post-processing method based on the hue, saturation, and value color space for image recognition and error calculation is proposed to analyze the migration and sweeping effects of catalyst fluids. This method involves identifying images captured by a digital camera, calculating area ratios, and determining recognition errors. The results show that catalyst fluids exhibit the best viscosity reduction ratio (80.0%) and the largest dispersion area ratio (55.7%) when the catalyst concentration is 4 wt. %, the injection velocity is 0.01 ml/min, the reaction temperature is 200 °C, and the reaction time is 24 h. With the increase in injection velocity, the viscosity reduction effect becomes worse. The viscosity reduction effect is improved with the increase in reaction temperature. With the growth of reaction time, the viscosity reduction effect increases and then becomes gentle. The combined mechanism of catalytic viscosity reduction and sweeping effects of catalyst fluids in porous media is proposed. This study provides a theoretical foundation for the large-scale development of heavy oil catalytic viscosity reduction.

Prediction of FAE concentration based on Physics-Informed Neural Network

Abstract The dispersion concentration distribution of Fuel-Air Explosives (FAE) directly affects fuse warhead matching, thereby influencing the FAE weapon’s effectiveness. Therefore, real-time simulation of the concentration distribution during the fuel dispersion process is a key technology for the design of FAE weapon’s fuse warhead matching. This paper simplifies the FAE fuel dispersion process, constructs a model of the fuel dispersion process, establishes fuel diffusion control equations, designs the training process of Physics Informed Neural Networks (PINN) to fit the fuel diffusion process, and predicts of concentration of fuel clouds at different spatial coordinates at different times. The global relative error of the predicted values for the three physical fields is approximately 15% to 20%, providing a new method for simulating experiments on the dispersion process of FAE.

Preparation, morphology, antiradical and biological activity of quercetin-containing nanoparticles of zein and their submicron aggregates

Nanoparticles of corn prolamine protein zein (NPQ) containing 0.005–0.26 g/g quercetin (Q) were prepared by desolvation of a 25–30 mg/mL ethanol protein solution containing the encapsulated compound with an aqueous polystyrene sulfonate. The size of zein nanoparticles and their aggregates was characterized by dynamic light scattering and atomic force microscopy; the quercetin content – by the Folin-Ciocalteu assay. While the quercetin/zein ratio in solution is less than 0.08 g/g, the polyphenol is quantitatively included in the nanoparticles, and their hydrodynamic diameter is 60–75 nm. As the quercetin/zein ratio rises to 0.20 g/g, the average particle diameter increases to 150 nm. In concentrated dispersions, aggregates with a diameter of 500–600 nm are formed. The kinetics of quercetin release from NPQ with different mass fractions of Q in distilled water and solutions simulating the environment of the stomach and intestines at 37 °C were studied.Zein nanoparticles exhibit weak activity in the reaction with ABTS cation-radicals. Quercetin encapsulated in the zein matrix generally retains the antiradical activity characteristic of the free flavonoid, however, the rate of decolorization of ABTS cation-radicals decreases due to the prolonged release of quercetin from NPQ. The cytoprotective properties of quercetin in zein nanoparticles are significantly reduced and manifest themselves only in partial preservation of the integrity of cell membranes and a decrease in the release of lactate dehydrogenase from UV-C irradiated HaCaT cells. In contrast to free quercetin, the introduction of Q in zein nanoparticles or their submicron aggregates increases the number of metabolically dead UV-C-irradiated HaCaT cells, enhancing the cytotoxic effect of UV radiation. Empty zein aggregates of submicron size have a similar effect.

Numerical analysis of solute transport and longitudinal dispersion coefficients in vegetated flow

Reasonable estimates of longitudinal dispersion coefficients are essential for predicting solute dispersion processes. However, the current knowledge of solute dispersion processes in vegetated waters is limited. In this work, we coupled a refined hydrodynamic model with scalar transport equations to simulate the flow field and dispersion process of solutes in water under the effect of vegetation. First, the proposed numerical model was verified using laboratory experiments, revealing the excellent performance of the coupled model in complex conditions. Eight different cases were subsequently simulated to analyse the effects of the upstream flow rate and vegetation height on the streamwise velocity, solute concentration, and longitudinal dispersion coefficients. The simulation results show that the upstream flow variation exerts a marked effect on the streamwise velocity and flow field within the vegetation zone, with a velocity difference within the shear layer reaching 54.7 % for an upstream flow of 0.018 m3·s-1. The height of the vegetation affects both the velocity profile and solute dispersion. Placing emergent vegetation upstream can enhance solute dispersion in the longitudinal direction. The correlation analysis reveals that the longitudinal dispersion coefficients obtained using the routing producer are close to those determined using the theoretical method, with correlation coefficients reaching 0.75. This work presents the appropriate application range and parameters that must be considered in deriving formulas for longitudinal dispersion coefficients.

Effect of Solid Content on Rheological, Mechanical, and Thermal Properties of Adipic Acid‐Based Flame Retardant Polyurethane Dispersion

ABSTRACTThe solid concentration of polyurethane dispersion is an important aspect of the coating application. In the present work, anionic waterborne polyurethane was prepared by reacting PPG‐100, adipic acid, and THPP‐based monophosphate polyester diol with IPDI. The formulation was done by varying solid concentrations of dispersion. The chemical structure was confirmed using FTIR and NMR. The surface morphology of coated panels was analyzed by SEM that shows as solid concentration increases surface roughness increases. The rheological property indicates that the solid concentration of FRPUDs increases viscosity and storage modulus whereas loss modulus decreases. The thermal degradation rate increases from 348°C to 354°C with increased solid concentration. LOI increases from 26% to 29% with increase in solid concentration. Tensile strength increases from 10.5 to 14.8 MPa with an increase in solid concentration in dispersion. Flexibility or elongation increases from 268% to 299% with a decrease in solid concentration. Scratch hardness in coating increases with increase in solid concentration.

Interface-mediated nano-downsizing for concentrated black phosphorene dispersions in volatile systems

Black phosphorene (BP) shows great potential as a versatile two-dimensional material. Its scalable preparation and practical applications often rely on processable forms such as dispersions. However, the inherent instability of concentrated BP dispersions and the use of high-boiling point solvents pose significant challenges, particularly during solvent removal. Here, we introduce an interface-mediated nano-downsizing strategy to achieve uniformly small lateral dimensions in few-layered BP nanosheets. This method enables the efficient and scalable preparation of concentrated phytic acid (PA)-stabilized BP dispersions in low-boiling point solvents such as acetone. These dispersions remain stable for at least 18 days in nitrogen and 8 days in air, demonstrating efficient photothermal conversion (45.8 %) and excellent photothermal stability. The volatile system facilitates the rapid preparation of uniform BP coatings on various substrates at room temperature. This work provides a general method for preparing concentrated nano-dispersions in volatile solvents, optimizing their performance for various applications.

Adding More Shape to Nanoscale Reference Materials─LiYF4:Yb,Tm Bipyramids as Standards for Sizing Methods and Particle Number Concentration.

The increasing industrial use of nanomaterials calls for the reliable characterization of their physicochemical key properties like size, size distribution, shape, and surface chemistry, and test and reference materials (RMs) with sizes and shapes, closely matching real-world nonspheric nano-objects. An efficient strategy to minimize efforts in producing nanoscale RMs (nanoRMs) for establishing, validating, and standardizing methods for characterizing nanomaterials are multimethod nanoRMs. Ideal candidates are lanthanide-based, multicolor luminescent, and chemically inert nanoparticles (NPs) like upconversion nanoparticles (UCNPs), which can be prepared in different sizes, shapes, and chemical composition with various surface coatings. This makes UCNPs interesting candidates as standards not only for sizing methods, but also for element-analytical methods like laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), quantitative bioimaging methods like X-ray fluorescence computed tomography (XFCT), and luminescence methods and correlative measurements. Here, we explore the potential of two monodisperse LiYF4:Yb,Tm bipyramids with peak-to-peak distances of (43 ± 2) nm and (29 ± 2) nm as size standards for small-angle X-ray scattering (SAXS) and tools for establishing and validating the sophisticated simulations required for the analysis of SAXS data derived from dispersions of nonspheric nano-objects. These SAXS studies are supplemented by two-dimensional (2D)-transmission electron microscopy measurements of the UCNP bipyramids. Additionally, the particle number concentration of cyclohexane dispersions of these UCNP bipyramids is determined by absolute SAXS measurements, complemented by gravimetry, thermogravimetric analysis (TGA), and inductively coupled plasma optical emission spectrometry (ICP-OES). This approach enables traceable particle number concentration measurements of ligand-capped nonspheric particles with unknown chemical composition.

Thermo- and light responsive microgels for efficient brackish and seawater forward osmosis desalination

Forward osmosis desalination presents a promising solution to address water shortages in areas near brackish or seawater sources. This study investigates the use of thermo-responsive poly(N-isopropyl acrylamide-rand‑sodium acrylate) microgels as innovative draw agents for forward osmosis desalination. The drawing ability and responsiveness of these microgels are significantly influenced by the charged comonomer content. Unlike bulk hydrogels, these microgels, owing to their core-shell morphology, maintain thermo-responsivity even at higher comonomer content. Incorporating graphene oxide as a light absorber allows for partial heating, required to reach the transition temperature, to be obtained using UV light radiation. In forward osmosis, microgels can be used either in a dried state or as a concentrated aqueous dispersion. A sample with 25 mol% charged units achieved a balance between water flux and responsiveness. It reached fluxes of 2.84, 4.79 and 4.39 L·m−2·h−1 for the dried state, 40 wt% and 20 wt% dispersions, respectively, when tested with 5 g·L−1 brackish water. Furthermore, a 40 wt% dispersion drew 35 g·L−1 seawater at a flux of 1.36 L·m−2·h−1. This sample, which contains graphene oxide, exhibited a volume phase transition temperature at 41 °C that can be achieved through UV light radiation or natural sunlight exposure. Water separation from the microgels was accomplished through filtration under UV-light radiation with a power of 4 kW·m−2, at 2–4 bar pressure, with a microfiltration membrane and a flux of 36 L·m−2·h−1. These findings highlight the potential of these thermo-responsive microgels for efficient forward osmosis desalination.

Effect of deflocculants on the rheological behavior of high alumina matrix suspensions for self-flowing bauxite castable

This study investigates the influence of commercially available polyphosphates and polycarboxylate ethers as deflocculants on aqueous suspensions containing high alumina cement (HAC), reactive alumina (RA), and various matrix compositions. Utilizing rheological methods, the research explores the interplay between dispersant concentration and the apparent viscosity and flow behavior of RA suspensions and matrix mixtures. The Casson model is employed to effectively describe the obtained flow data. Moreover, the study discerns specific impacts of polycarboxylate ethers on the thickening properties of matrix mixtures characterized by varying RA and HAC contents. Additionally, the research evaluates the physical and mechanical properties of low-cement bauxite castables treated with a range of polycarboxylate esters. The findings demonstrate that all deflocculated suspensions exhibit Non-Newtonian structured fluid behavior with a discernible yield stress (τ0) at shear rates below 20 s-1. At higher shear rates, there is a significant reduction in apparent viscosity, aligning well with the Casson model. Comparative assessments, based on flow curve values τ0, elucidate differing degrees of suspension flocculation depending on the type of dispersant used.

In-situ carbon integration on atomically dispersed platinum metal oxide nanocomposites for hydrogen evolution reaction

In this study, a novel in-situ carbon growth technique by a modified sol gel synthesis method is presented. The carbon support developed on a transition metal oxide composite transforms the electronic conductivity and is engineered for hydrogen evolution reaction by a dispersion of unit atomic concentration of platinum. Through two different synthesis techniques, platinum dispersion is implemented on the metal oxide-carbon system, one by direct sol-gel technique and another by chemical reduction technique, whereby a homogeneous dispersion of the noble metal on the composite is achieved. Carbon-based cerium oxide and titanium oxide composites are used as the base material, and one atomic percentage of platinum metal is ensured while synthesizing each of the carbon composites. The functionality of these catalysts towards hydrogen evolution reaction in a 0.5 M H2SO4 acidic media revealed the synthesis technique's uniqueness and the effect of metal support interaction that plays a vital role in the electrocatalytic activity. The intrinsic activity of the titania system, along with enhanced metal support interaction due to highly enriched platinum availability on the surface of the substrate, provides for strong electrochemical activity. The titanium oxide carbon composite with platinum dispersed by hydrazine reduction exhibited the finest activity with an overpotential of just 44 mV at j = 10 mA/cm2 and a tafel slope of 118 mV/dec. The gas chromatographic analysis on platinum supported titania catalyst showcased better performance by a margin of four times than the commercial three weight percentage platinum supported carbon.

Process analytical technology based quality assurance of API concentration and fiber diameter of electrospun amorphous solid dispersions

In this study, a novel quality assurance system was developed utilizing Process analytical technology (PAT) tools and artificial intelligence (AI). Our goal was to monitor the critical quality attributes (CQAs) like drug concentration, morphology and fiber diameter of electrospun amorphous solid dispersion (ASD) formulations with fast at-line techniques. Doxycycline-hyclate (DOX), a tetracycline-type antibiotic was used as a model drug with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) as the matrix excipient. The water-based formulations were electrospun with high-speed electrospinning (HSES). Raman and NIR sensors and machine vision-based color measurement techniques were employed to accurately determine the drug concentration. Given that morphology can influence the solubility of the drug, a convolutional neural network (CNN)-based AI model was developed to examine this property and detect manufacturing defects. Additionally, the diameter of electrospun fibrous samples was measured using camera images and a trained AI model, enabling rapid analysis of fiber diameter with results similar to that of scanning electron microscopy (SEM). These methods and models demonstrate potential in-line analytical tools, offering rapid, cheap and non-destructive analysis of ASD formulations.