Blue Dye Research Articles

An investigation of photocatalytic and biological properties of Croton bonplandianum-mediated Ag-Cu bimetallic nanoparticles

The green synthesis of nanoparticles using plant parts and their essence is considered an archetypal tactic in material synthesis for environmental beneficence. Multitudinous metal nanoparticles with potential bioactivities have been prepared based on plant extract. This study's main objective is synthesizing Ag-Cu bimetallic nanoparticles (Ag-Cu BMNPs) using leaf extract of Croton bonplandianum L (CB). Furthermore, its photocatalytic, antibacterial, anti-fungal, and anti-tuberculosis activities are systematically investigated in detail. The surface morphology of the prepared sample is shown to be highly porous, with an average grain size of ∼ 16 nm. The FTIR spectra exhibited that the phytomolecules from CB leaf extract serve as a capping and reductantfor forming Ag-Cu BMNP. Brunauer-Emmitte-Teller (BET) comprehends the CB leaf extract to be an active, cost-effective, reusable, and high surface area catalyst. The sample exhibited improved photocatalytic activity with an efficiency of 92.31 % at the moderate catalyst dose of 30 mg against methylene blue (MB) dye. Ag-Cu BMNPs exhibited a 17 mm inhibition zone at higher concentrations against both gram (+ve) and gram (−ve) bacterial strains. Also, the synthesized Ag-Cu BMNPs produced a clear inhibition zone of 16 mm and 15 mm at lower concentrations. The anti-fungal activity against A. flavus and C. albicans at higher and lower concentrations produced a clear inhibition zone of 17 mm,15 mm, and 6 mm, 9 mm, respectively. In addition, the anti-tuberculosis activity against Mycobacteria tuberculosis exhibited good results at a 0.4 µg/mL concentration for the synthesized sample. Moreover, Ag-Cu BMNPs enhanced their biological ability and did not increase their cytotoxicity, which provides a potential for the clinical applications of Ag-Cu BMNPs. In general, the suggested method for producing Ag-Cu bimetallic nanoparticles is successful in combating microbiological diseases.

Protein Kinase C Beta II Inhibitor Conjugated with Myristic Acid and Trans-Activator of Transcription improves intracellular delivery and cardiovascular protection in porcine myocardial ischemia/reperfusion injury

Introduction: While timely reperfusion of oxygenated blood is critical during resuscitation of ischemic myocardium, oxidative stress during reperfusion still leads to ischemia/reperfusion (I/R) injury and ultimately, cardiomyocyte death. The major sources of oxidative stress targeted in this study are NADPH oxidase (NOX-2) and mitochondria, which are both activated by protein kinase C beta II (PKCβII). In previous studies with an ex-vivo rat heart I/R model, Myristic Acid (Myr) and Trans-Activator Transcription (Tat; YGRKKRRQRRR) conjugated PKCβII inhibitor (Myr-Tat-PKCβII-; N-Myr-Tat-CC-SLNPEWNET) showed cardioprotective effects and decreased infarct size. In this study, we hypothesized that Myr-Tat-PKCβII- will offer cardioprotective effects in comparison with a scrambled peptide control (Myr-Tat-PKCβII-scram; N-Myr-Tat-CC-WNPESLNTE) in an in-vivo porcine myocardial I/R model. Methods: Regional I(1 hour)/R(3 hours) was induced in Male Yorkshire pigs (38-50kg) by inflating a balloon to occlude the Left Anterior Descending Artery (LAD) at the level of the second diagonal branch (supplies 40% of anterior left ventricle) and then deflating it to allow for reperfusion. Then, a bolus of either Myr-Tat-PKCβII- or Myr-Tat-PKCβII-scram (20ng/kg; ~100pmol in blood) was immediately administered into the LAD. Cardiac function and injury were measured by monitoring changes in ejection fraction (EF) and through routine measurements of serum creatine phosphokinase (CPK), troponin I, and myoglobin, respectively. After I/R, the hearts were stained with 1% Evans Blue dye to identify the area at risk (AR) and 1% triphenyltetrazolium chloride to determine the area of necrosis (AN). Infarct size was then quantified (AN/AR) and all data was analyzed via Student’s t-test. Results: Analysis showed that Myr-Tat-PKCβII- significantly restored EF to within 1.40.7% of baseline compared to controls which only restored EF to within 6.42.1% (p<0.05) of baseline EF. Myr-Tat-PKCβII- showed a significant increase in serum myoglobin levels at 1 hr of reperfusion (1362.1 83.4 μg/mL, n=4) compared to scrambled control (202.1197.3 μg/mL, n=3 p<0.05). Myr-Tat-PKCβII- reduced infarct size to 10.0±2.8%; n=4; compared to scrambled control hearts (28.5±8.3%; n=6; p<0.05). CPK and Troponin I levels were comparable in both groups. These results suggest that Myr-Tat-PKCβII- can help prevent cardiac injury when given immediately after an ischemic event. Conclusions: Data from ex-vivo rat heart I/R model, coupled with data from this in-vivo porcine myocardial I/R model indicate the effcacy of Myr-Tat-PKCβII- in preventing oxidative stress-induced myocardial I/R injury when given at the beginning of reperfusion. These findings suggest that Myr-Tat-PKCβII- could be useful in the clinical setting when administered immediately after cardiac resuscitation. Future studies include the treatment of rat cardiomyocyte cells with Myr-Tat-PKCβII- prior to 24 hr hypoxia/24 hr reoxygenation, followed by cell viability assays compared to untreated control. This additional data can help determine the optimal dose to use in a 12 week survival study using the same porcine myocardial I/R protocol. Funding: This study was funded by the Philadelphia College of Osteopathic Medicine, Department of Biomedical Sciences, Division of Research, and the Center for Chronic Diseases of Aging, the National Heart, Lung & Blood Institute at NIH (grant # 1R43HL160338-01) and Young Therapeutics, LLC. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Pyroelectric performance of tantalum doped NBT-6BT bulk ceramics

In the present investigation, Ta5+ doped 0.94NBT-0.06BT-0.02Zn-xTa (x=0, 0.25, 0.5 and 1) are synthesized using a solid-state route for pyroelectric analysis. The Zn doping in NBT-6BT increases depolarization temperature, while Ta doping enhances the pyroelectric coefficient, which is beneficial for pyroelectric applications. The pyroelectric coefficient at room temperature is found as 1.03×10−4 C.m−2 °C−1, 3.8×10−4 C.m−2 °C−1, 3.53×10−4 C.m−2 °C−1 and 2.79×10−4 C.m−2 °C−1 for NBT-6BT-2Zn, NBT-6BT-2Zn-0.25Ta, NBT-6BT-2Zn-0.5Ta and NBT-6BT-2Zn-1Ta, respectively. The maximum pyroelectric open circuit current/voltage of 25 nA/100 V is reported for NBT-6BT-2Zn-0.25Ta. The NBT-6BT-2Zn-xTa is used for the methylene blue dye degradation for water treatment via pyrocatalysis.

Kidney disease associated with pre-pubertal obesity initiates pathological alterations in the brain of Dahl salt-sensitive rats

Childhood/pre-pubertal obesity (PPO) is implicated in the development of chronic kidney disease (CKD), and there is evidence that PPO also increases the risk of developing Alzheimer disease (AD) later in life. In the current study, we aim to investigate the correlation between CKD and the development of AD-like pathology in a rat model of CKD associated with PPO. We hypothesize that systemic inflammation due to PPO exacerbates CKD and induces AD-like pathology in the brain at older age. In our preliminary studies, we utilized the Dahl salt sensitive leptin receptor mutant rat (SSLepRmutant), which is a novel model of PPO. 6-week-old Dahl salt-sensitive (SS) (control, n=3) and SSLepRmutant rats (n=5) were monitored for proteinuria every 3 weeks, for a 12-week period. Throughout the study, we observed significantly elevated proteinuria in SSLepRmutant rats (Week-6: 337±81 mg/day, Week-9: 371±147 mg/day, Week-18: 1920±318 mg/day) compared to SS rats (Week-6: 25±7 mg/day, Week-9: 35±39 mg/day, Week-18: 35±33 mg/day). At 18-week, creatinine levels were significantly higher in SSLepRmutant rats (1.5±0.5 mg/dL) versus SS rats (0.4±0.03 mg/dL) indicating CKD. Additionally, we found significant elevation of triglycerides in SSLepRmutant rats (5134±1211 mg/dL) compared to SS rats (79±21 mg/dL). To investigate the brain pathology, we performed immunochemical analysis (dot-blot assay) using A11 antibody to determine the levels of Amyloid-beta oligomers (Aβo). Our results show that there was tendency for Aβo levels to be increased in the brains from obese SSLepRmutant rats compared to SS. Finally, we tested the permeability of the blood-brain barrier to Evans blue dye and observed that the brain of SSLepRmutant rats was more permeable to the dye compared to SS rats as early as 8 weeks of age. Overall, these results indicate that PPO obesity not only increases the susceptibility to develop CKD but also causes Alzheimer-like pathology during the prepubescent stage. NIDDK (DK109133) and AG (AG057842) awarded to Jan M. Williams. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Gelsenicine disrupted the intestinal barrier of Caenorhabditis elegans

Gelsemium elegans Benth. (G. elegans) is a traditional medicinal herb that has anti-inflammatory, analgesic, sedative, and detumescence effects. However, it can also cause intestinal side effects such as abdominal pain and diarrhea. The toxicological mechanisms of gelsenicine are still unclear. The objective of this study was to assess enterotoxicity induced by gelsenicine in the nematodes Caenorhabditis elegans (C. elegans). The nematodes were treated with gelsenicine, and subsequently their growth, development, and locomotion behavior were evaluated. The targets of gelsenicine were predicted using PharmMapper. mRNA-seq was performed to verify the predicted targets. Intestinal permeability, ROS generation, and lipofuscin accumulation were measured. Additionally, the fluorescence intensities of GFP-labeled proteins involved in oxidative stress and unfolded protein response in endoplasmic reticulum (UPRER) were quantified. As a result, the treatment of gelsenicine resulted in the inhibition of nematode lifespan, as well as reductions in body length, width, and locomotion behavior. A total of 221 targets were predicted by PharmMapper, and 731 differentially expressed genes were screened out by mRNA-seq. GO and KEGG enrichment analysis revealed involvement in redox process and transmembrane transport. The permeability assay showed leakage of blue dye from the intestinal lumen into the body cavity. Abnormal mRNAs expression of gem-4, hmp-1, fil-2, and pho-1, which regulated intestinal development, absorption and catabolism, transmembrane transport, and apical junctions, was observed. Intestinal lipofuscin and ROS were increased, while sod-2 and isp-1 expressions were decreased. Multiple proteins in SKN-1/DAF-16 pathway were found to bind stably with gelsenicine in a predictive model. There was an up-regulation in the expression of SKN-1:GFP, while the nuclear translocation of DAF-16:GFP exhibited abnormality. The UPRER biomarker HSP-4:GFP was down-regulated. In conclusion, the treatment of gelsenicine resulted in the increase of nematode intestinal permeability. The toxicological mechanisms underlying this effect involved the disruption of intestinal barrier integrity, an imbalance between oxidative and antioxidant processes mediated by the SKN-1/DAF-16 pathway, and abnormal unfolded protein reaction.

The Physiological Responses to Stellate Ganglion Blockade under Ultrasound-Guidance in the Rat

The stellate ganglion (SG) is an essential component of the sympathetic nervous system, where inhibition via local anesthetics is used as a practical approach to manage many clinical disorders, including regional pain syndrome and cardiovascular diseases. However, this procedure is often technically challenging, with side effects including pneumothorax and vascular injection. Ultrasound-guided SG blockade (SGB) is currently adopted as a more effective method than blind injection techniques as it allows for visualizing SG’s location. However, there is not yet enough information on the physiological responses of this procedure. The present study examined physiological changes following ultrasound-guided SGB in normal rats. We hypothesized that ultrasound-guided SGB is a safe and effective method to inhibit sympathetic nerves in the rat. Male Sprague-Dawley rats (310-350 g) were anesthetized with 2-4% isoflurane and placed on the animal monitor platform (VisualSonics Vevo, SR200) that allowed for monitoring and recording the electrocardiogram, respiratory rate, and body temperature. Normal saline (0.9%) or 1.0-1.5% lidocaine mixed with Chicago blue dye was loaded in a 1 ml insulin syringe with a 26 G needle. Each tested solution in 40-60 μl was injected into the right or left SG region once under ultrasound guidance (VisualSonics Vevo 3100 LT). Ten minutes after the injection, rats were allowed to recover from the anesthesia, and the status of the eyelid and the general condition were examined. Ptosis was observed on the ipsilateral side as the lidocaine was administered to the right (n=9) or left (n=7) sides of SG, indicating the successful execution of SGB. No ptosis was noted in any controls as normal saline was injected into the right (n=6) or left (n=6) SG. Respiratory rate and body temperature were unchanged following the injection in either the right or left side in any control or treatment groups. Heart rate (HR) was significantly decreased after administering lidocaine (354 ± 14 vs. 292 ± 16 bpm, P = 0.008; pre- vs. after-injection) but not normal saline into right SG. Reduced HR lasted for about 7-10 minutes. HR was unaltered after injecting lidocaine or normal saline into the left SG. These data imply that sympathetic nerves controlling HR are likely predominantly associated with right SG. Besides, no abnormal behaviors were noted in any rat. Chicago blue dye was confirmed to be distributed in the SG region. No bleeding and tissue damage were evident in the injected SG area. The results suggest that non-invasive ultrasound-guided SGB is likely a safe and effective approach with a small injection volume to block sympathetic nerves in the rat, which sheds light on its employment in experimental research and clinical practice. Research fund from AEON Biopharma, Inc. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Exploring the potential of olive pomace derived activated charcoal as an efficient adsorbent for methylene blue dye: a comprehensive investigation of isotherms, kinetics, and thermodynamics

Methylene blue (MB) is a heterocyclic aromatic chemical compound used as a dye in various dyeing processes. The accumulation of such an organic compound poses a significant threat to both the environment and human health. Therefore, numerous biological, physical, and chemical processes have been established to remove MB dye, with adsorption being the most predominant dye-based treatment technology. In this context, the aim of this work was to evaluate the adsorption properties of activated carbon derived from olive pomace against methylene blue. To this end, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR) analyses were carried out to confirm the adsorption of MB on carbon structures. In addition, the effect of contact time, pH, initial dye concentration, adsorbent dose, and temperature on the adsorption efficiency of MB was investigated. On the other hand, kinetic and isothermal models were used to further understand the adsorption mechanism, which showed a good correlation with the pseudo-second-order kinetic model and the Langmuir isotherm. Finally, thermodynamic analysis showed favorable conditions for physisorption, with the process being both endothermic and spontaneous.

Abstract 1122: Endothelial Cd36 Mediates Lipid-induced Stiffening Of Aortic Endothelium And Western Diet-induced Barrier Disruption

Introduction: Western diet (WD) associates with elevations in blood lipids. Endothelial cells (EC) uptake lipids through scavenger receptors such as CD36. In our studies we demonstrated that exposure to lipids induces a stiffening response in ECs, with in vivo studies showing that this stiffening is abrogated in mice with a global CD36 knockout. Hypothesis: WD associates with aortic barrier disruption. in vitro studies have demonstrated that EC stiffening correlates with barrier disruption. It is our hypothesis that EC stiffening mediates WD-induced aortic barrier disruption in an endothelial CD36-dependent manner. Methods: To generate a model of endothelial-specific CD36 deficiency, we crossed tamoxifen-inducible Cre mice with an EC-promoter with CD36 fl/fl mice. Cre only mice are employed as controls. At the end of the study window, aortas are excised for assessment of EC stiffening via atomic force microscopy. Separate cohorts are assessed for barrier disruption via quantification of Evans blue dye (EBD) leakage or VE-cadherin junctional thickness. Inhibition of CD36 in vitro was accomplished with SSO. For cell experiments we employed long-chain fatty acids (LCFAs), lipid ligands for CD36. Results: WD induced significant stiffening of the aortic endothelium [p<0.05]. This phenomenon was only observed in male (n=5-6) and not female (n=3-10) mice. EC stiffening associated with aortic barrier disruption as indicated by increased EBD permeation (n=3-8) and increased VE-cadherin thickness (n=3-4) [p<0.05]. Use of an endothelial-specific CD36 deficiency significantly abrogated stiffening and barrier disruption [p<0.05]. Controls demonstrated no effects by tamoxifen (n=2-3). Exposure to 5 μM of palmitic and stearic acids (saturated LCFAs) results in stiffening while exposure to oleic acid (unsaturated LCFA) does not (n=5-12) [p<0.05]. Palmitic acid-induced EC stiffening was shown to be dependent on CD36 (n=5-6) and activation of RhoA protein kinase (n=3-8) [p<0.05]. Conclusions: Our results demonstrate that endothelial CD36 is required for WD-induced EC stiffening and subsequent disruption of the aortic barrier. Furthermore, our results suggest that CD36 mediates EC stiffening through its role as scavenger receptor to saturated LCFAs.

The effect of Ce doping on the structural, optical, and photocatalytic degradation of Mn–Co nanoferrites

This work demonstrates the preparation of Ni0.5Mn0.25Co0.25CexFe2-xO4 spinel nanoferrites (NMCCF nanoferrites) using the citrate combustion method. This study also investigated the characteristics of their structure, optics, and ability to degrade under light. The lattice strain and crystallite size of each NMCCF nanoferrite were measured by evaluating the XRD results using Williamson-Hall plots. The crystallite size was between 40 and 78 nm. The hopping lengths, bond lengths, surface areas, and densities of all NMCCF nanocrystals were measured and calculated. FTIR analysis showed two strong frequency bands at 571 and 390 cm−1, which are characteristic of spinel ferrites. SEM was used to investigate the particle size, composition, and distribution of the nanoferrites in the NMCCF sample. Scanning electron microscopy (SEM) analysis revealed the presence of spherical NMCCF nanoparticles and their tendency to aggregate. The Kubelka-Munk function and Tauc plots were used to predict the direct allowed Eg value of the NMCCF samples. NMCCF0, NMCCF1, NMCCF2, NMCCF3, NMCCF4, and NMCCF5 exhibited bandgap values of 1.515, 1.545, 1.506, 1.507, 1.499, and 1.473 eV, respectively. The behavior of Eg can be explained based on two criteria: doping impact and particle size. A comparative analysis of the photocatalytic degradation of the ideal sample (Ni0.5Mn0.25Co0.25Ce0.1Fe1.9O4) and other published photocatalytic materials demonstrated that the NMCCF5 nanoferrite exhibited a greater ability to remove methylene blue dye (97.38 %, within 60 min) compared to those materials. In addition, this comparative investigation demonstrated the enhanced stability of photocatalytic degradation capability exhibited by the current nanoferrites (with just a 1.55 % loss in efficiency after five cycles). This paper introduces an innovative method for producing spinel nanoferrites, with a specific focus on their structural, optical, and photocatalytic properties, which can be useful in the field of water treatment.

WITHDRAWN: Recombinant osteopontin stabilizes the blood brain barrier following subarachnoid hemorrhage in rats

Background and PurposeRecombinant osteopontin (rOPN) decreases neuronal cell death and brain edema and improves the neurological scores following subarachnoid hemorrhage (SAH) in rats. The molecular mechanisms of the preservation of blood-brain barrier of rOPN following SAH in rats were examined in this study. MethodsAdult rats were divided into 3 groups: sham, vehicle, and treatment groups. Each animal in the SAH group underwent a surgical procedure to induce SAH, and the brains was harvested at 24 hours for analysis. For the mechanism part of the study two additional groups were operated and treated with Fib-14 and Wortmannin additional to rOPN. rOPN was administered via the nasal route and neurological scores as well as brain water content were evaluated at 24 hours after SAH induction. The blood brain barrier (BBB) permeability was evaluated using Evans Blue dye extravasation. The expressions of tight junction proteins claudin-3, claudin-5, occludin and the phosphorylation of β-catenin were examined using Western blot analysis. ResultsrOPN improved neurological scores and reduced brain edema at 24 hours after SAH. The BBB preservation action of rOPN is mediated in part through stabilizing β-catenin and increasing expression of tight junction proteins, claudin-3, claudin-5, and occludin. rOPN is thought to exert its effects through FAK activated PI3K-Akt pathway. ConclusionSince BBB disruption is one of the major pathophysiology of EBI after SAH, rOPN may be a promising drug to maintain BBB integrity and functions in SAH treatment.

Temporal evolution of optical and photocatalytic properties of hydrothermally synthesized EDTA-encapsulated CdS spherical nanostructures

EDTA encapsulated CdS spherical nanocrystals have been prepared via hydrothermal approach at three different reaction times 16 h, 20 h, and 24 h. The XRD investigation confirms the formation of cubic and hexagonal mixed phase of CdS while HRSEM image validates the synthesis of spherical nanocrystals. The EDX spectra confirm the purity of the samples. The optical properties have been studied using UV–Vis and photoluminescence spectroscopic techniques. The PL spectrum at 20 h reaction time shows utmost intensity. The vibrational properties of the synthesized CdS samples have been investigated using FTIR technique in the range of 500 – 4000 cm−1. The photocatalytic properties of EDTA@CdS spherical nanocrystals to degrade methyl blue dye have been studied under sunlight.

Liposomal Nanocarriers of Preassembled Glycocalyx Restore Venular Permeability in Sepsis: Assessed Quantitatively with a Novel Microchamber System

Background: The endothelial glycocalyx (EG), covering the luminal side of endothelial cells, regulates vascular permeability and senses wall shear stress. In sepsis, EG undergoes degradation leading to increased permeability and edema formation. We hypothesized that restoring EG integrity using liposomal nanocarriers of preassembled glycocalyx (LNPG) will restore normal venular permeability in a lipopolysaccharide (LPS)-induced sepsis model of mice. Methods: To test this hypothesis, we designed a unique perfusion microchamber in which the vascular permeability of isolated and cannulated mice mesenteric venules could be assessed by measuring the concentration of Evans blue dye (EBD) by fluorescent spectroscopy in microliter-samples of extravascular solution (ES). Results: Histamine-induced time- and dose-dependent increases in EBD in the ES could be measured, confirming the sensitivity of the microchamber system. Notably, the histamine-induced increase in permeability was significantly attenuated by histamine receptor (H1) antagonist, triprolidine hydrochloride. Subsequently, mice were treated with LPS, or LPS + LNPG. Compared to control mice, venules from LPS-treated mice showed a significant increased permeability, which was significantly reduced by LNPG administration. Moreover, in the presence of wall shear stress, intraluminal administration of LNPG significantly reduced the permeability in isolated venules from LPS-treated mice. Conclusion: Our newly developed microchamber system can quantitatively measure the permeability of isolated venules. LPS-induced sepsis increases permeability of venules that is attenuated by in vivo LNPG administration, which is also reestablished endothelial vasomotor responses to shear stress. Thus, LNPG presents a promising therapeutic potential for restoring EG function and thereby mitigating the increased permeability in sepsis. Support: National Institute of Health [grant number: HL144528, Dong Sun] and the Uehara Memorial Foundation [grant number: 202241049, Shinya Ishiko) and Hungarian Academy of Sciences Post-Covid 2021-34 (AK) and MIT of Hungary, National Research, Development, and Innovation Fund, OTKA K 132596 (AK). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Highly effective ultrafiltration membranes based on plastic waste for dye removal from water.

Applicable and low-cost ultrafiltration membranes based on waste polystyrene (WPS) blend and poly vinylidene fluoride (PVDF) were effectively cast on nonwoven support using phase inversion method. Analysis was done into how the WPS ratio affected the morphology and antifouling performance of the fabricated membranes. Cross flow filtration of pure water and various types of polluted aqueous solutions as the feed was used to assess the performance of the membranes. The morphology analysis shows that the WPS/PVDF membrane layer has completely changed from a spongy structure to a finger-like structure. In addition, the modified membrane with 50% WPS demonstrated that the trade-off between selectivity and permeability is met by a significant improvement in the rejection of the membrane with a reduction in permeate flux due to the addition of PVDF. With a water permeability of 50 LMH and 44 LMH, respectively, the optimized WPS-PVDF membrane with 50% WPS could reject 81% and 74% of Congo red dye (CR) and methylene blue dye (MB), respectively. The flux recovery ratio (FRR) reached to 88.2% by increasing PVDF concentration with 50% wt. Also, this membrane has the lowest irreversible fouling (Rir) value of 11.7% and lowest reversible fouling (Rr) value of 27.9%. The percent of cleaning efficiency reach to 71%, 90%, and 85% after eight cycles of humic acid (HA), CR, and MB filtration, respectively, for the modified PS-PVDF (50%-50%). However, higher PVDF values cause the membrane's pores to become clogged, increase the irreversible fouling, and decrease the cleaning efficiency. In addition to providing promising filtration results, the modified membrane is inexpensive because it was made from waste polystyrene, and as a result, it could be scaled up to treat colored wastewater produced by textile industries. PRACTITIONER POINTS: Recycling of plastic waste as an UF membrane for water/wastewater treatment was successfully prepared and investigated. Mechanical properties showed reasonable response with adding PVDF. The modified membrane with 50% PS demonstrated that the trade-off between selectivity and permeability is met by a significant improvement in the rejection.

Effect of the Photoreduction Process on the Self-Cleaning and Antibacterial Activity of Au-Doped TiO2 Colloids on Cotton Fabric.

This study aims at understanding the effect of the photoreduction process during the synthesis of gold (Au)-doped TiO2 colloids on the conferred functionalities on cotton fabrics. TiO2/Au and TiO2/Au/SiO2 colloids were synthesized through the sol-gel method with and without undergoing the photoreduction step based on different molar ratios of Au:Ti (0.001 and 0.01) and TiO2/SiO2 (1:1 and 1:2.3). The colloids were applied to cotton fabrics, and the obtained photocatalytic self-cleaning, wet photocatalytic activity, UV protection, and antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria were investigated. The obtained results demonstrated that the photoreduction of Au weakened the self-cleaning effect and reduced the photocatalytic activity of coated fabrics. Also, an excess amount of Au deteriorated the photocatalytic activity under both UV and visible light. The most efficient self-cleaning effect was obtained on fabrics coated with a ternary TiO2/Au/SiO2 colloid containing ionic Au, where it decomposed coffee and red-wine stains after 3 h of illumination. Adding silica (SiO2) made the fabrics superhydrophilic and led to greater methylene blue (MB) dye adsorption, a faster dye degradation pace, and more efficient stain removal. Moreover, the photoreduction process affected the size of Au nanoparticles (NPs), weakened the antibacterial activity of fabrics against both types of tested bacteria, and modestly increased the UV protection. In general, the photoactivity of Au-doped colloids was influenced by the synthesis method, the ionic and metallic states of the Au dopant, the concentration of the Au dopant, and the presence and concentration of silica.

Effect of surfactants (cetyl trimethyl ammonium-bromide, ethyl di-tetra amine and polyacrylamide) on the synthesis of zinc oxide for photocatalytic application

In this work, we report the effect of cetyl trimethyl ammonium bromide (CTAB), ethyl di-tetra amine (EDTA) and polyacrylamide as surfactants on synthesis of zinc oxide for photocatalytic application. The ZnO nanoparticles were synthesized with and without the surfactants and characterized using powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR). In addition to this, the morphology of zinc oxide prepared in the absence and presence of these surfactants investigated through scanning electron microscopy (SEM). As confirmed from XRD and FTIR characterization results, the use of different surfactants did not affect the composition of ZnO nanomaterials. The photocatalytic activities were investigated by the degradation of methylene blue (MB) dye under sunlight irradiation. To optimize the effects of operational parameters, the study was carried out as a function of dye concentration, catalyst dose, and pH on the degradation efficiency of the photocatalysts. The optimum values of catalyst dose, dye concentration and pH of solution were found to be 0.09 g, 5 mg/L and 10, respectively. The ZnO nanomaterials prepared with CTAB surfactant showed highest degradation efficiency of 98% indicating potential application for practical decontamination of wastewater from toxic organic pollutants. KEY WORDS: Surfactants, Zinc oxide nanoparticles, Photocatalysis, Methylene blue Bull. Chem. Soc. Ethiop. 2024, 38(4), 923-935. DOI: https://dx.doi.org/10.4314/bcse.v38i4.9

Adsorption and bacterial performance of Nd2O3 modified Ag nanoparticles with enhanced degradation of methylene blue

Our study focused on the optical behavior, methylene blue (MB) dye degradation potential, antibacterial performance, and silver and trioxide mineral interaction with different bacterial species. We found that the addition of silver nanoparticles (Ag NPs) to neodymium oxide (Nd2O3) resulted in a significant response, with an enlargement of the inhibition zone for bacterial species such as Staphylococcus aureus and Escherichia coli. Specifically, the inhibition zone for S. aureus increased from 9.3 ± 0.5 mm for pure Nd2O3 to 16.7 ± 0.4 mm for the Ag/Nd2O3 nano-composite, while for E. coli, it increased from 8.8 ± 0.4 mm for Nd2O3 to 15.9 ± 0.3 mm for Ag/Nd2O3. Furthermore, the optical behavior of the composites showed a clear band-gap narrowing with the addition of Ag NPs, resulting in enhanced electronic localization. The direct and indirect transitions reduced from 6.7 to 6.1 eV and from 5.2 to 2.9 eV, respectively. Overall, these results suggest that the Ag/Nd2O3 nano-composite has potential applications in sensor industries and water treatment, thanks to its enhanced optical behavior, antibacterial performance, and efficient MB degradation capabilities. In terms of MB degradation, the Ag/Nd2O3 mixed system exhibited more efficient degradation compared to pure Nd2O3. After 150 min, the MB concentration in the mixed system decreased to almost half of its starting point, while pure Nd2O3 only reached 33%.

Decolourization of Methylene Blue by using Eucalyptus Globulus Leaf Powder as a Adsorbent

In the present study, the feasibility of using low-cost adsorbent Eucalyptus Globulus leaf powder for the cationic dyes adsorption from aqueous solutions have been investigated. Batch adsorption studies are conducted to study conducted to the different parameters are adsorbent dosage of 2-20 g/L, initial dye concentration of 50-250 mg /L, Temperature of 293oK, 303 oK and 313 oK on adsorption of methylene blue dye at equilibrium time of 80 minutes respectively and optimal pH of 5.0. The equilibrium data is analysed with isotherm models are Langmuir and Freundlich and kinetic models are Pseudo-first order, Pseudo-second order model. The adsorption equilibrium and kinetic data fitted well to Freundlich isotherm model for methylene blue dye and Pseudo-second order model for methylene blue dyes. The adsorption is an Endothermic and it is energetically favourable adsorption. The result demonstrates that Eucalyptus Globulus leaf powder could be employed as effective and low-cost adsorbent for the removal of methylene blue and from aqueous solutions.

BREWERY WASTE FOR INDIGO BLUE ADSORPTION

Brewery waste (BW) is among the natural adsorbents that have been evaluated for different chemical pollutants removal present in the aqueous medium. In this work, we investigated the BW capacity to remove the commercial indigo blue dye (IB) from laboratory aqueous solutions and river water samples. Results utilizing laboratory distilled water showed a satisfactory maximum capacity (166.94 mg/g) of BW for IB. The ∆G value (-16.53 Kj/mol) and other parameters reveal a favorable adsorptive process. Furthermore, tests in glass columns using river water samples enriched with IB (1,000 mg/L) revealed high BW efficiency for IB removal (96.0 %). These results are important to demonstrate that BW can be more a new alternative for IB removal from water. In addition, this study provides an alternative for the reuse of BW.

In vitro analysis of material micro-leakage in pit and fissure sealants

A preferable choice of material offers superior resistance against micro-leakage for clinical applications in preventing dental caries in pits and fissures is of interest. A total of 45 extracted human premolars were cleaned, stored in a saline solution, and randomly divided into three groups, each intended for treatment with one of the sealants: Fuzi VII, ClinPro, and Embrace Wetbond. The application of the sealants followed the manufacturers' instructions strictly. The teeth were subjected to thermal cycling to simulate oral conditions. Marginal micro-leakage was then assessed by dye penetration method using a 0.5% methylene blue dye. Teeth were sectioned, and dye penetration was measured under a stereomicroscope. The results showed that all the tested materials exhibited some degree of micro-leakage. Within the limitations of this in vitro study, it was concluded that Embrace Wetbond exhibited superior performance in terms of minimizing marginal micro-leakage among the tested pit and fissure sealants.

Environmentally friendly silver nanoparticles synthesized from Verbascum nudatum var. extract and evaluation of its versatile biological properties and dye degradation activity

In the present study, green synthesis of silver nanoparticles (VNE-AgNPs) via Verbascum nudatum extract was carried out for the first time. The synthesized AgNPs were characterized by different spectral methods such as UV–vis, FTIR, XRD, TEM, and EDAX. According to TEM analyses, the average size range of AgNPs was 17–21 nm, and the dominant peaks in the 111°, 200°, 221°, and 311° planes in the XRD pattern indicated the Ag-NPs FCC crystal structure. FTIR data showed that VNE-AgNPs interacted with many reducing, capping, and stabilizing phytochemicals during green synthesis. VNE-AgNPs had higher antibacterial activity against S. aureus and E. coli bacterial strains with a maximum inhibition zone of 21 and 18 mm, respectively, than penicillin 5 IU, used as a positive control in the study. The cytotoxic effect of VNE-AgNPs appeared at a concentration of 50 µg/mL in L929 cells and 5 µg/mL in cancer (A549) cells. When the impact of VNE-AgNPs and C-AgNPs on inflammation was compared, it was found that VNE-AgNPs increased TNF-α levels (333.45 ± 67.20 ng/mg-protein) statistically (p < 0.05) more than TNF-α levels (256.92 ± 27.88 ng/mg-protein) in cells treated with C-AgNPs. VNE-Ag-NPs were found to have a degradation efficiency of 65% against methylene blue (MB) dye within 3 h.Graphical