Dye Diffusion Research Articles

Studies of third order nonlinearity and thermal diffusivity of C3OC dye using thermal lens technique

An FT-IR spectrometer and a UV–Visible spectrometer were utilised in order to characterise the Cyanidin-3-O-glucoside chloride (C3OC) dye. The dye’s thermally induced optical nonlinearity was measured in a dimethylformamide solvent using an adjustable diode-pumped solid-state (DPSS) laser at 473 nm. The optical response was measured using the Z-scan technique. The dye showed negative and large nonlinear refractive index) NRX) values, with high nonlinear absorption coefficients (NBO). Because of its ability to change with concentration, the NRX is a viable candidate for applications in the field of nonlinear optics. Thermal lens (THS) technique was used to investigate thermo-optical properties and the NRX. The optical limiter capabilities of the C3OC dye are being investigated as a potential use.

Study of substituents-regulated dyeing properties in non-aqueous media systems based on MD simulation and DFT

To investigate the relationship between N-acetoxyethyl group and dyeing properties of disperse dyes in D5 non-aqueous medium dyeing system, the adsorption and diffusion behaviors of three disperse dyes with different structures were studied by molecular dynamics (MD). The diffusion coefficients, the planar distribution densities of dyes in different directions, and the intermolecular interaction energies were calculated. Molecular dynamics simulation (MD) was used to calculate molecules polarity index (MPI). Meanwhile, the practical dyeing experiments also were investigated to compare with simulated results. The results showed that the adsorption and diffusion behavior of disperse dyes with different structures were significantly different. Compared with dye B257, D-1 and D-2 are more easily adsorbed and diffused into the interior of the fiber because of the introduction of polar acetoxyethyl group. Moreover, the diffusion coefficient of D-2 in the fiber was relatively low, indicating that the combination between dye and polyester fiber was stable. XY plane distribution density and MPI revealed that the introduction of acetoxyethyl was beneficial to increase the adsorption amount of dye on the fiber, which was mainly related to the high binding energy between dye molecule and polyester fiber. The results of dyeing experiments showed that the decreased solubility of disperse dyes in the D5 medium was conducive to improving the dyeing rate of disperse dyes. This was consistent with the simulated interaction between dyes and D5. This study will provide a basis for further rapid and accurate development and selection of disperse dyes with high dyeing rate in non-aqueous medium systems.

From Bioink to Tissue: Exploring Chitosan-Agarose Composite in the Context of Printability and Cellular Behaviour

This study presents an innovative method for producing thermosensitive bioink from chitosan hydrogels saturated with carbon dioxide and agarose. It focuses on a detailed characterisation of their physicochemical properties and potential applications in biomedicine and tissue engineering. The ORO test approved the rapid regeneration of the three-dimensional structure of chitosan–agarose composites in a unidirectional bench press simulation test. The diffusion of dyes through the chitosan–agarose hydrogel membranes strongly depended on the share of both polymers in the composite and the molecular weight of the dyes. Glucose, as a nutrient marker, also diffused through all membranes regardless of composition. Biocompatibility assessment using MTT tests on 46BR.1N fibroblasts and HaCaT keratinocytes confirmed the safety of the bioink. The regenerative potential of the bioink was confirmed by efficient cell migration, especially HaCaT. Long-term viability studies showed that chitosan–agarose scaffolds, unlike the agarose ones, support cell proliferation and survival, especially 14 days after bioink extrusion. Experiments in a skin wound model in mice confirmed the biocompatibility of the tested dressing and the beneficial action of chitosan on healing. Studies on vessel formation in chicken embryos highlight the potential of the chitosan–agarose composition to enhance proangiogenic effects. This composition meets all entry criteria and possesses excellent biological properties.

Steady and transient modeling of dye-sensitive solar cells: The impact of electrode thickness and dye specifications

Investigating the impact of dye compounds on cell performance is crucial for advancing dye-sensitized solar cells (DSSCs). This research focuses on the sensitivity analysis of the effect of critical parameters to enhance DSSC efficiency using a thermo-electric numerical model. These parameters include dye types, trapping parameters, diffusion coefficients, and photoanode thickness. When the type of dye changes, in fact, both physical and chemical properties (molar absorption coefficient, etc.) Change, but to avoid the complexity of solving the equations and only to evaluate the effect of the absorption wavelength range on the cell performance only changes in physical properties are considered. The model calculates steady and transient currents under actual weather conditions and sunlight. It incorporates time/space-dependent relationships for increased accuracy and examines electron, iodide, and triiodide ion interactions under varying environmental conditions. Key concepts include the quasi-Fermi level and the multiple trap model, assuming that trapping processes are faster than electron transport and recombination. The results showed that increasing the trapping parameter can affect the transient current behavior, also increasing the thickness of the photoanode and the wavelength range of the dye increases the efficiency of the cell, so that the N749-BD provides the best performance. The findings provide insights into current–voltage characteristics, electron production, and the effects of photoanode thickness and dye types on cell performance, offering pathways for optimizing DSSC technology.

Efficient removal of organic pollutants on sponge-type inorganic adsorbent derived from spent cotton fiber/layered double hydroxides

For the whole life cycle of the textile industry, the disposal of printing and dyeing wastewater and the reuse of spent fibers were two of the main environmental problems. In this work, activated carbon fiber/layered double oxides (ACF/LDO) were prepared by the pyrolysis of spent cotton fiber/layered double hydroxides (LDH) composite. Compared to 2D structure LDH, 3D hierarchical ACF/LDO was formed by introducing activated carbon nanofibers as a skeleton. ACF/LDO had excellent adsorption properties for organic dye and the maximum adsorption capacity of acid red 27 (AR27) exceeded 800 mg/g. Due to the memory effect of LDH, the interconversion of ACF/LDO to ACF/LDH was observed during the adsorption and regeneration process. Meanwhile, the shrinkage and expansion of adsorbent occurred, which was similar to that of a sponge absorbing water. During the adsorption process, the average pore diameter of the adsorbent increased as ACF/LDO was converted to ACF/LDH, which increased the diffusion of organic dye inside the pores. On the contrary, the specific surface area and pore structure were restored during the regeneration process. Therefore, this composite displayed excellent adsorption capacity and repeatability, with no significant decrease was observed in adsorption capacity even after five consecutive cycles. The adsorption mechanism revealed that the removal of AR27 was dominated by electrostatic attraction and π-π interactions. The experiment provided a new strategy of treating wastewater with waste fiber.

The plasticisation model of dye diffusion: Part 2

AbstractTemperature dependent equilibrium dye adsorption data reported for Chlorazol Fast Scarlet 8B, Durazol Red 2B and Chrysophenine G on cotton, CV and CUP fibres and Durazol Grey RG on cotton and CV fibres in the presence of a constant amount of added inorganic electrolyte between 60°C and 90°C, as well as Chrysophenine G on cellophane sheet in the presence of varying amounts of added inorganic electrolyte, between 60°C and 97.5°C, was re‐evaluated using the Williams‐Landel‐Ferry equation. The results obtained suggest that the plasticisation model of dye diffusion appears to offer a reasonable explanation of the temperature dependent equilibrium adsorption of direct dyes on cellulosic fibres/polymers.

Influence of a cross-linker agent on mechanical and other properties of polysiloxane based scintillators

Polysiloxane scintillators (PSS) are of great interest due to their neutron and gamma-ray (n/γ) discrimination capability and excellent radiation hardness. However, one major drawback is their low mechanical hardness. To address this issue, we present a cross-linking agent, 1,3-diethenyl-1,3-dimethyl-1,3-diphenyldisiloxane (DS), incorporated into PSS to study its effects on various physical properties. It was found that the enhanced inter-chain entanglement of covalently bonded polymer chains by the DS cross-linker significantly improved the mechanical hardness and optical properties. Gravimetric analysis (TGA) indicated a slightl improvement in stability during thermal degradation. This cross-linker at 0-17 wt% concentrations has also slightly positive impact on the PSD performance as demonstrated by measurements of pulse shape discrimination (PSD) using a 238Pu-Be neutron source. The improved cross-linking density helped prevent both the generation of free molecule radicals and diffusion of fluorophore dyes. Consequently, the cross-linked samples remained transparent with no dye precipitation, even after 12 months of storage.

Diffusion Mapping with Diffractive Optical Elements for Periodically Patterned Photobleaching.

Fourier transform-fluorescence recovery after photobleaching (FT-FRAP) using a diffractive optical element (DOE) is shown to support distance-dependent diffusion analysis in biologically relevant media. Integration of DOEs enables patterning of a dot array for parallel acquisition of point-bleach FRAP measurements at multiple locations across the field of view. In homogeneous media, the spatial harmonics of the dot array analyzed in the spatial Fourier transform domain yield diffusion recovery curves evaluated over specific well-defined distances. Relative distances for diffusive recovery in the spatial Fourier transform domain are directly connected to the 2D (h,k) Miller indices of the corresponding lattice lines. The distribution of the photobleach power across the entire field of view using a multidot array pattern greatly increases the overall signal power in the spatial FT-domain for signal-to-noise improvements. Derivations are presented for the mathematical underpinnings of FT-FRAP performed with 2D periodicity in the photobleach patterns. Retrofitting of FT-FRAP into instrumentation for high-throughput FRAP analysis (Formulatrix) supports automated analysis of robotically prepared 96-well plates for precise quantification of molecular mobility. Figures of merit are evaluated for FT-FRAP in analysis for both slow diffusion of fluorescent dyes in glassy polymer matrices spanning several days and model proteins and monoclonal antibodies within aqueous solutions recovering in matters of seconds.

Lumbar Intrathecal Injection in Adult and Neonatal Mice.

This article describes a step-by-step process of lumbar intrathecal injection of Evans blue dye and AAV9-EGFP in adult (2-month-old) and neonatal (postnatal day 10) mice. Intrathecal injection is a clinically translatable technique that has already been extensively applied in humans. In mice, intrathecal injection is considered a challenging procedure that requires a trained and experienced researcher. For both adult and neonatal mice, lumbar intrathecal injection is directed into the L5-L6 intervertebral space. Intrathecally injected material enters the cerebrospinal fluid (CSF) within the intrathecal space from where it can directly access the central nervous system (CNS) parenchyma. Simultaneously, intrathecally injected material exits the CSF with pressure gradient and enters the endoneurial fluid and ultimately the peripheral nerves. While in the CSF, the injectable material also enters the bloodstream and systemic circulation through the arachnoid villi. A successful lumbar intrathecal injection results in adequate biodistribution of the injectable material in the CNS, PNS, and peripheral organs. When correctly applied, this technique is considered as minimally invasive and non-disruptive and can be used for the lumbar delivery of any solute. © 2024 Wiley Periodicals LLC. Basic Protocol 1: C57BL/6 adult and P10 mice lumbar intrathecal injection Basic Protocol 2: Tissue collection and preparation for evaluating Evans blue dye diffusion Basic Protocol 3: Tissue collection and preparation for immunohistochemistry staining Basic Protocol 4: Tissue collection and vector genome copy number analysis.

The plasticisation model of dye diffusion: Part 1 introduction

The plasticisation model of dye diffusion: Part 1 introduction

The roles of elevated temperature and carriers in the dyeing of polyester fibres using disperse dyes: Part 4 plasticisation model of dye diffusion

AbstractThis review concerns the application of disperse dyes to poly(ethylene terephthalate) fibres using aqueous immersion dyeing processes and the roles of both elevated dyeing temperatures and carriers in the dyeing system. In this part of the paper, a novel plasticisation model of dye diffusion is proposed which reflects the crucially important mechanistic role that water‐induced fibre/polymer plasticisation adopts in the diffusion of disperse dyes within polyester and other types of polymeric material.

Pathways of dye spread after injections in the paraspinal spaces-A cadaveric study.

The erector spinae plane (ESP) block is the most sought-after block since its inception. However, it is more of dorsal rami block with unpredictable ventral diffusion to the paravertebral area. We injected dye in ESP and other paraspinal spaces to study and compare the dye diffusion pattern along the neuroaxis and paraspinal region in human cadavers. In six soft-embalmed cadavers (12 specimens), 20 mL methylene blue dye (erector spinae plane and paravertebral space) or indocyanine green dye (inter-ligament space) was injected bilaterally using an in-plane ultrasound-guided technique at the level of the costotransverse junction of fourth thoracic vertebrae. Dye spread was evaluated bilaterally in the coronal plane in the paravertebral and intercostal spaces from the 1st and the 12th rib. Axial and sagittal sections were performed at the level of the 4th thoracic vertebrae. After cross sections, the extent of dye spread was investigated in ESP, inter-ligament, and paravertebral spaces. The staining of the ventral and dorsal rami and spread into the intercostal spaces was evaluated. ESP injection was mainly restricted dorsal to the costotransverse foramen and did not spread anteriorly to the paravertebral space. The paravertebral injection involved the origin of the spinal nerve and spread laterally to the intercostal space. The inter-ligament space injection showed an extensive anterior and posterior dye spread involving the ventral and dorsal rami. Following ESP injection, there was no spread of the dye anteriorly to the paravertebral space and it only involved the dorsal rami. Inter-ligamentous space injection appears to be the most promising block as dye spread both anteriorly to paravertebral space and posteriorly toward ESP.

Studies on Fluorescence Quenching, Decay Rate Parameters, Dipole Moment, Rotational Diffusion of 3-(benzo[d]thiazol-2-yl)-7-(diethylamino)-2H-chromen-2-one Laser Dye in Excited Singlet State: Temperature Effect.

The effect of temperature on the absorption and emission characteristics of 3-(benzo[d]thiazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (3BT7D2H-one) laser dye in glycerol solvent has been studied by the steady-state method. Fluorescence intensity decreases with an increase in temperature and shifts towards a shorter wavelength. Parameters like fluorescence lifetime, rate constants, activation energy, and dipole moment (using the thermochromic method) are determined experimentally. Also, the temperature effect on rotational diffusion of 3BT7D2H-one laser dye is studied and also estimated theoretical and experimental hydrodynamic volumes.

“All in one” nanoprobe Au-TTF-1 for target FL/CT bioimaging, machine learning technology and imaging-guided photothermal therapy against lung adenocarcinoma

The accurate preoperative diagnosis and tracking of lung adenocarcinoma is hindered by non-targeting and diffusion of dyes used for marking tumors. Hence, there is an urgent need to develop a practical nanoprobe for tracing lung adenocarcinoma precisely even treating them noninvasively. Herein, Gold nanoclusters (AuNCs) conjugate with thyroid transcription factor-1 (TTF-1) antibody, then multifunctional nanoprobe Au-TTF-1 is designed and synthesized, which underscores the paramount importance of advancing the machine learning diagnosis and bioimaging-guided treatment of lung adenocarcinoma. Bright fluorescence (FL) and strong CT signal of Au-TTF-1 set the stage for tracking. Furthermore, the high specificity of TTF-1 antibody facilitates selective targeting of lung adenocarcinoma cells as compared to common lung epithelial cells, so machine learning software Lung adenocarcinoma auxiliary detection system was designed, which combined with Au-TTF-1 to assist the intelligent recognition of lung adenocarcinoma jointly. Besides, Au-TTF-1 not only contributes to intuitive and targeted visualization, but also guides the following noninvasive photothermal treatment. The boundaries of tumor are light up by Au-TTF-1 for navigation, it penetrates into tumor and implements noninvasive photothermal treatment, resulting in ablating tumors in vivo locally. Above all, Au-TTF-1 serves as a key platform for target bio-imaging navigation, machine learning diagnosis and synergistic PTT as a single nanoprobe, which demonstrates attractive performance on lung adenocarcinoma.Graphical

The roles of elevated temperature and carriers in the dyeing of polyester fibres using disperse dyes: Part 1 fundamental aspects

AbstractThis review concerns the application of disperse dyes to poly(ethylene terephthalate) (PET) fibres using aqueous immersion dyeing processes and the roles of both elevated dyeing temperatures and carriers in such dyeing systems. This part of the paper presents a review of the fundamental properties and characteristics of PET fibres, disperse dyes and dyeing accelerants. In the next part of the paper, the various theories and concepts that have been proposed to explain the promotional effects imparted by elevated dyeing temperatures and carriers to disperse dye uptake on PET and other types of fibre, are reviewed and analysed, from the viewpoints of the essential physico‐chemical aspects of both the aqueous disperse dye/PET and disperse dye/carrier/PET systems. Later parts of the paper will present a mechanistic model of the disperse dye adsorption process based on dye solubility as well as a novel plasticisation model of dye diffusion.

Superficial Inferior Epigastric Artery Flap: Vascular Pattern and Territory Across the Midline.

Superficial inferior epigastric artery (SIEA) flap offers a significant advantage of lower donor site morbidity over other abdominal-based flaps for breast reconstruction. However, the inconsistent anatomy and territory across the midline remains a major issue. This study aimed to investigate the SIEA and determine its pattern and territory across the midline. Twenty cadavers were studied. Ipsilateral dye was injected to the dominant SIEA. Dissection was performed to evaluate the SIEA origin, artery and vein pattern, vessel diameter, and dye diffusion territory. Overall, three SIEA patterns were identified: bilateral presence (45%), ipsilateral presence (30%), and bilateral absence (25%). The territory depended on the vessel course and dominant SIEA diameter, not on its common origin from the femoral artery, at the pubic tubercle level. Regarding the midline territory (pubic tubercle level to umbilicus), SIEA (type 1a) with a diameter of ≥1.4 mm on either side supplied at least half the distance, whereas SIEA with a diameter of <1 mm was limited to the suprapubic area. Designing a SIEA flap island across the midline is feasible when contralateral SIEA is present to augment the contralateral territory (e.g., type 1a SIEA) or in SIEA with a common/superficial external pudendal artery origin. Preoperative imaging studies are important for confirming the SIEA system. When the diameter at the origin of the SIEA flap is larger than 1.4 mm, the blood supply to the ipsilateral and contralateral sides is sufficient to enable safe flap elevation.

Design a dual-response two-photon fluorescent probe for simultaneous imaging of mitochondrial viscosity and peroxynitrite in a thrombosis model

BackgroundVenous thromboembolism is a sudden cardiovascular disease that can lead to death, and its pathologic development is closely related to vascular viscosity and inflammation. However, direct evidence from in vivo is really scarce. The key limitation is that the combined probes cannot detect multiple markers simultaneously, which may lead to unreliable results. Therefore, to develop a single probe that can simultaneously monitor the variations of viscosity in the vascular microenvironment as well as inflammation level during venous thrombosis. ResultsA dual-responsive two-photon fluorescent probe, Cou-ONOO, was designed and synthesized. Cou-ONOO provides a visualization tool for monitoring the viscosity of the vascular as well as the inflammatory marker ONOO‾ during thromboembolism via dual-channel simultaneous imaging. As a single probe that can recognize dual targets, Cou-ONOO effectively avoids the problems from unreliable results caused by complex synthesis and differences in intracellular localization, diffusion, and metabolism of different dyes as using combinatorial probes. Using Cou-ONOO, simultaneous imaging the variations of viscosity and ONOO‾at the cellular and tissue levels was successfully performed. In addition, Cou-ONOO also successfully visualized and tracked the viscosity of the vascular microenvironment and ONOO‾ during venous embolism in mice. SignificanceExperimental results show that both viscosity and inflammation are abnormally overexpressed in the microenvironment at the thrombus site during venous thrombosis. An intuitive visualization tool to elucidate the variations of viscosity as well as inflammation level in the vascular microenvironment during thrombosis was provided, which will facilitate a better clinical understanding of the pathological process of thrombosis.

Explorative Image Analysis of Methylene Blue Interactions with Gelatin in Polypropylene Nonwoven Fabric Membranes: A Potential Future Tool for the Characterization of the Diffusion Process.

This manuscript explores the interaction between methylene blue dye and gelatin within a membrane using spectroscopy and image analysis. Emphasis is placed on methylene blue's unique properties, specifically its ability to oscillate between two distinct resonance states, each with unique light absorption characteristics. Image analysis serves as a tool for examining dye diffusion and absorption. The results indicate a correlation between dye concentrations and membrane thickness. Thinner layers exhibit a consistent dye concentration, implying an even distribution of the dye during the diffusion process. However, thicker layers display varying concentrations at different edges, suggesting the establishment of a diffusion gradient. Moreover, the authors observe an increased concentration of gelatin at the peripheries rather than at the center, possibly due to the swelling of the dried sample and a potential water concentration gradient. The manuscript concludes by suggesting image analysis as a practical alternative to spectral analysis, particularly for detecting whether methylene blue has been adsorbed onto the macromolecular network. These findings significantly enhance the understanding of the complex interactions between methylene blue and gelatin in a membrane and lay a solid foundation for future research in this field.

Development of novel parameters for characterising scale morphology of wool fibre and its correlation with dye diffusion coefficient of acid dye

This paper reports the development of novel surface parameters which can be used to characterise the scale structure of wool fibres obtained from different breeds. Scanning electron microscopy and subsequent image analysis technique were used to study wool fibres from Leicester, Dartmoor, Ryeland and Herdwick breeds of sheep. Novel scale parameters related to wool fibre’s effective chemical diffusion pathway were developed. Namely, the total scale perimeter per 100 µm fibre length and scale perimeter index, which is the total scale perimeter per 100 µm length divided by the fibre diameter. Wool fibres obtained from different breeds showed significant differences in their scale pattern with the change in fibre diameter. The scale perimeter per 100 µm length increased with the fibre diameter and showed a polynomial correlation. It was also demonstrated that an increase in the diameter of the wool fibre resulted in an increase in the apparent dye diffusion coefficient, which contrasts the established theory that finer fibres are associated with a higher dyeing rate. The increase in effective diffusion pathway (total scale perimeter per 100 µm) for the wool fibres (among different breeds) resulted in a higher dye diffusion rate at the initial phase of dyeing (liquor to surface).

Investigating the effects of polypropylene-TiO2 loading on the performance of polysulfone/polyetherimide ultrafiltration membranes for azo dye removal: Experimental and molecular dynamics simulation

This research paper delves into developing and analyzing advanced composite ultrafiltration (UF) membranes specifically tailored for water treatment and dye removal applications. The composite UF membranes were designed using a combination of polysulfone (PSF), polyetherimide (PEI), and polypropylene-80 wt% TiO2 (PPTiO2) to create the active layer, while a flat polyamide (PA) serves as the support material and is prepared via the spin/spray-coating method. Three different PPTiO2 contents were considered, including 5 wt% (M05), 10 wt% (M10), and 15 wt% (M15). The properties of these membranes were characterized using a range of techniques, including Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Atomic Force Microscopy (AFM), contact angle measurements, mechanical testing and zeta potential. Performance evaluation involved filtering Reactive Red 120 (RR120) and Direct Blue 6 (DB6) solutions through the prepared composite membranes at 5 bar and demonstrates that the optimized membrane M15 exhibited remarkable water permeability of 82.13 L.m−2.h−1 bar−1 and maximum dye rejections of 92.82 % and 97.07 % for DB6 and RR120 respectively. Furthermore, molecular dynamics (MD) simulations were conducted to analyze the thermal and structural properties of the membranes. The simulations reveal that increasing the content of PPTiO2 reduced membrane pore size, consequently limiting dye mobility and diffusion. This study is the first-of-its-kind to explore the effect of PPTiO2 content on the membrane (PSF/PEI) properties; the optimized composite UF membrane showcases exceptional water permeability and dye rejection performance, making it a promising candidate for water treatment and dye removal applications.