Catalytic innovations: Improving wastewater treatment and hydrogen generation technologies.

The effective reduction of hazardous organic pollutants in wastewater is a pressing global concern, necessitating the development of advanced treatment technologies. Pollutants such as nitrophenols and dyes, which pose significant risks to both human and aquatic health, making their reduction particularly crucial. Despite the existence of various methods to eliminate these pollutants, they are not without limitations. The utilization of nanomaterials as catalysts for chemical reduction exhibits a promising alternative owing to their distinguished catalytic activity and substantial surface area. For catalytically reducing the pollutants NaBH4 has been utilized as a useful source for it because it reduces the pollutants quiet efficiently and it also releases hydrogen gas as well which can be used as a source of energy. This paper provides a comprehensive review of recent research on different types of nanomaterials that function as catalysts to reduce organic pollutants and also generating hydrogen from NaBH4 methanolysis while also evaluating the positive and negative aspects of nanocatalyst. Additionally, this paper examines the features effecting the process and the mechanism of catalysis. The comparison of different catalysts is based on size of catalyst, reaction time, rate of reaction, hydrogen generation rate, activation energy, and durability. The information obtained from this paper can be used to steer the development of new catalysts for reducing organic pollutants and generation hydrogen by NaBH4 methanolysis.

Manganese cobalt-MOF@carbon nanofiber-based non-enzymatic histamine sensor for the determination of food freshness.

Early detection of histamine in foodstuffs/beverages could be useful in preventing various diseases. In this work, we have prepared a free-standing hybrid mat based on manganese cobalt (2-methylimodazole)-metal organic frameworks (Mn-Co(2-MeIm)MOF) and carbon nanofibers (CNFs) and explored as a non-enzymatic electrochemical sensor for determining the freshness of fish and bananas based on histamine estimation. As-developed hybrid mat possesses high porosity with a large specific surface area and excellent hydrophilicity those allow easy access of analyte molecules to the redox-active metal sites of MOF. Furthermore, the multiple functional groups of the MOF matrix can act as active adsorption sites for catalysis. The Mn-Co(2-MeIm)MOF@CNF mat-modified GC electrode demonstrated excellent electrocatalytic activities toward the oxidation of histamine under acidic conditions (pH = 5.0) with a faster electron transfer kinetics and superior fouling resistance. The Co(2-MeIm)MOF@CNF/GCE sensor exhibited a wide linear range from 10 to 1500 µM with a low limit of detection (LOD) of 89.6 nM and a high sensitivity of 107.3 µA mM-1 cm-2. Importantly, as-developed Nb(BTC)MOF@CNF/GCE sensor is enabled to detect histamine in fish and banana samples stored for different periods of time, which thus indicates its practical viability as analytical histamine detector.

In situ retrieval and correction of aberrations in moldless lenses using Fourier ptychography.

Liquid droplets cured at low temperatures or using ultraviolet light are primary approaches for fabricating refractive lenses without molds. Until now the performance of moldless lens fabrication process relied heavily on this step to precisely control the shape of each liquid droplet. Hence, a major hurdle in lenses fabricated from liquid droplets is the large variability of droplet shapes because they are sensitive to small amounts of interfacial forces. The shape of the final droplet critically affects the imaging performance of the lenses and cannot be reversed easily. Here, we aim to overcome this hurdle by performing in situ aberration correction using Fourier ptychography techniques. We demonstrate, for the first time, that computational optics can reverse high amounts of optical aberrations in moldless lenses and achieve high resolution imaging. In terms of imaging resolution, we successfully increased the resolving power of low powered moldless elastomer lenses by almost three-fold, from a numerical aperture of 0.035 to 0.099. The computational approach directly elucidates the spatially varying wavefront aberrations from each lens using the same imaging system. This provides direct feedback of droplet lens fabrication techniques without the need for advanced wavefront correction methods. The application of computational imaging onto moldless lenses, using consumer digital imaging systems, lends itself to the global efforts in decentralising high resolution image intensive scientific tools to the wider community.

Fabrication and Investigation of Deformable Rubber-Carbon Nanotube-Glue Gel-Based Impedimetric and Capacitive Tactile Sensors for Pressure and Displacement Measurements.

Carbon nanotube-glue composite gel-based surface-type elastic sensors with a cylindrical shape deformable (flexible) metallic body were fabricated for tactile pressure and compressive displacement sensing. The fabrication of the sensors was performed using the rubbing-in technique. The effect of the pressure and the compressive displacement on the capacitance and the impedance of the sensors were investigated at various frequencies (in the range of 1 kHz to 200 kHz). It was found that under the effect of pressure from 0 to 9 g/cm2, the capacitance increased by 1.86 and 1.78 times, while the impedance decreased by 1.84 and 1.71 times at the frequencies of 1 kHz to 200 kHz, respectively. The effect of displacement on the impedance and the capacitance of the device was also investigated at various frequencies from 1 kHz to 200 kHz. The results showed that under the effect of compressive displacement up to 25 µm, the impedance of the sensors decreased on average by 1.19 times, while the capacitance increased by 1.09 times, accordingly. The frequency response of the displacement sensor showed that it matched with the low-pass filter. The obtained results are explained based on changes in the shape and geometrical parameters of the cylindrical-shaped conductive body. These results have also been explained on the basis of the distance between the conductive plates of the capacitive sensors during compression, which takes place under the effect of applied pressure or displacement. Moreover, the design of the sensors is simple and easy to fabricate, and their use is also earthy. The fabricated sensors have great potential for commercialization.

An efficient wastewater treatment through reduction of organic dyes using Ag nanoparticles supported on cellulose gum beads.

This work reports silver nanoparticles (AgNPs) supported on biopolymer carboxymethyl cellulose beads (Ag-CMC) serves as an efficient catalyst in the reduction process of p-nitrophenol (p-NP) and methyl orange (MO). For Ag-CMC synthesis, first CMC beads were prepared by crosslinking the CMC solution in aluminium nitrate solution and then the CMC beads were introduced into AgNO3 solution to adsorb Ag ions. Field emission scanning electron microscopy (FE-SEM) analysis suggests the uniform distribution of Ag nanoparticles on the CMC beads. The X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis revealed the metallic and fcc planes of AgNPs, respectively, in the Ag-CMC catalyst. The Ag-CMC catalyst exhibits remarkable reduction activity for the p-NP and MO dyes with the highest rate constant (kapp) of a chemical reaction is 0.519 and 0.697 min-1, respectively. Comparative reduction studies of Ag-CMC with CMC, Fe-CMC and Co-CMC disclosed that Ag-CMC containing AgNPs is an important factore in reducing the organic pollutants like p-NP and MO dyes. During the recyclability tests, the Ag-CMC also maintained high reduction activity, which suggests that CMC protects the AgNPs from leaching during dye reduction reactions.

Development of silver-doped copper oxide and chitosan nanocomposites for enhanced antimicrobial activities.

Antimicrobial resistance (AMR) has emerged as a significant and pressing public health concern, posing serious challenges to effectively preventing and treating persistent diseases. Despite various efforts made in recent years to address this problem, the global trends of AMR continue to escalate without any indication of decline. As AMR is well-known for antibiotics, developing new materials such as metal containing compounds with different mechanisms of action is crucial to effectively address this challenge. Copper, silver, and chitosan in various forms have demonstrated significant biological activities and hold promise for applications in medicine and biotechnology. Exploring the biological properties of these nanoparticles is essential for innovative therapeutic approaches in treating bacterial and fungal infections, cancer, and other diseases. To this end, the present study aimed to synthesize silver@copper oxide (Ag@CuO) nanoparticles and its chitosan nanocomposite (Chi-Ag@CuO) to investigate their antimicrobial efficacy. Various established spectroscopic and microscopic methods were employed for characterization purposes, encompassing scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Subsequently, the antimicrobial activity of the nanoparticles was assessed through MIC (minimum inhibitory concentration), MBC (minimum bactericidal concentration), and well-disk diffusion assays against Pseudomonas aeruginosa, Acinetobacter baumannii Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans. The size of the CuO-NPs, Ag@CuO, and Chi-Ag@CuO NPs was found to be 70-120 nm with a spherical shape and an almost uniform distribution. The nanocomposites were found to possess a minimum inhibitory concentration (MIC) of 5 µg/mL and a minimum bactericidal concentration (MBC) of 250 µg/mL. Moreover, these nanocomposites generated varying clear inhibition zones, with diameters ranging from a minimum of 9 ± 0.5 mm to a maximum of 25 ± 0.5 mm. Consequently, it is evident that the amalgamation of copper-silver-chitosan nanoparticles has exhibited noteworthy antimicrobial properties in the controlled laboratory environment, surpassing the performance of other types of nanoparticles.

Silver oxide doped iron oxide/alginate nanocomposite coated cotton cloth for selective catalytic reduction of potassium ferricyanide.

Silver oxide doped iron oxide (Ag2O-Fe2O3) nanocatalyst was prepared and coated on cotton cloth (CC) as well as wrapped in sodium alginate (Alg) hydrogel. Ag2O-Fe2O3 coated CC (Ag2O-Fe2O3/CC) and Ag2O-Fe2O3 wrapped Alg (Ag2O-Fe2O3/Alg) were utilized as catalysts in reduction reaction of 4-nitrophenol (4-NP), congo red (CR), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]). Ag2O-Fe2O3/CC and Ag2O-Fe2O3/Alg were found to be effective and selective catalyst for the reaction of K3[Fe(CN)6]. Further amount of catalyst, K3[Fe(CN)6] quantity, amount of NaBH4, stability of catalyst and recyclability were optimized for the reaction of K3[Fe(CN)6] reduction. Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were appeared to be the stable catalysts by maintaining high activity during recyclability tests showing highest reaction rate constants (kapp) of 0.3472 and 0.5629 min-1, correspondingly. However, Ag2O-Fe2O3/CC can be easily recovered as compared to Ag2O-Fe2O3/Alg by simply removing from the reaction which is the main advantage of Ag2O-Fe2O3/CC. Moreover, Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were also examined in real samples and found useful for K3[Fe(CN)6] reduction involving real samples. The Ag2O-Fe2O3/CC nanocatalyst is a cost and time saving material for economical reduction of K3[Fe(CN)6] and environmental safety.

Zn/Al layered double hydroxide and carboxymethyl cellulose composite beads as support for the catalytic gold nanoparticles and their applications in the reduction of nitroarenes.

Until now, many efficient catalysts have been reported that are used for the reduction of nitroarenes. However, a catalyst reusability is a challenge that is often faced in practical environment. In this report, we designed a hydrogel composite (CMC-LDH), which act as support and making it possible to address this challenge. In this research work, zinc/aluminum based layered double hydroxides (Zn/Al LDH) have been assembled with carboxymethyl cellulose (CMC) to prepare CMC/LDH hydrogel beads. The CMC/LDH hydrogel beads were prepared by the ionotropic gelation method. For CMC/LDH/Au preparation, the already prepared CMC/LDH beads were kept in gold ion (Au3+) solution, and their subsequent reduction with sodium borohydride (NaBH4). For the characterization of the prepared samples different instrumental techniques, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy, and scanning electron microscopy (SEM) were adopted. For the catalytic evaluation of CMC/LDH/Au, it was utilized as a catalyst in 4-NP and 4-NA reduction reactions. The continuity of the reaction was monitored by a UV-visible spectrophotometer. Rate constant (kapp) of 0.48474 min-1 and 0.7486 min-1 were obtained for 4-NP and 4-NA reduction, respectively. The hydrogel beads were recycled and reused for up to five successive cycles without significantly changing their catalytic efficiency.

Chitosan hydrogel anchored phthalocyanine supported metal nanoparticles: Bifunctional catalysts for pollutants reduction and hydrogen production.

Metal nanoparticles possess high catalytic activity in various organic transformation reactions. A catalyst must be recovered and re-used effectively and economically to lower the overall reaction cost. The recovery of a catalyst remains a challenge due to their extreme small size. In this research work, catalytic metal nanoparticles were synthesized on Zn-phthalocyanine (ZnPc) and chitosan hydrogel (CH) composite which acts as catalyst support. The ZnPc-CH support facilitate the easy recovery of the loaded metal nanoparticles. Metal nanoparticles (M0) based on Cu0, Ag0, Ni0, Co0 and Fe0 were decorated inside and on ZnPc-CH hydrogel surface. The developed M0@ZnPc-CH were utilized for the enhanced selective reduction of toxins and hydrogen production by methanolysis and hydrolysis of NaBH4. Effective catalytic reduction and hydrogen generation was successfully achieved with Co0@ZnPc-CH and ZnPc-CH. Under optimized conditions, Co0@ZnPc-CH showed complete reduction of 4-nitrophenol (4-NP) in 8.0 min with the fast 4-NP reduction kinetics (K = 0.611 min-1). Among the developed catalysts, ZnPc-CH showed fast H2 generation with high H2 generation rate (HGR = 4100 mLg-1min-1) under optimized conditions. Metal leaching from Co0@ZnPc-CH was negligible during recycling of the catalyst, suggesting that it could be implemented to 4-NP treatment from real water samples. Similarly, ZnPc-CH could produce same quantity of H2 throughout 4 continuous cycles of durability testing without any deactivation and leaching and ZnPc-CH showed high stability, indicating the effectiveness of the catalyst to be applied for H2 production on large scale.

Shockproof Deformable Infrared Radiation Sensors Based on a Polymeric Rubber and Organic Semiconductor H2Pc-CNT Composite.

Polymeric rubber and organic semiconductor H2Pc-CNT-composite-based surface- and sandwich-type shockproof deformable infrared radiation (IR) sensors were fabricated using a rubbing-in technique. CNT and CNT-H2Pc (30:70 wt.%) composite layers were deposited on a polymeric rubber substrate as electrodes and active layers, respectively. Under the effect of IR irradiation (0 to 3700 W/m2), the resistance and the impedance of the surface-type sensors decreased up to 1.49 and 1.36 times, respectively. In the same conditions, the resistance and the impedance of the sandwich-type sensors decreased up to 1.46 and 1.35 times, respectively. The temperature coefficients of resistance (TCR) of the surface- and sandwich-type sensors are 1.2 and 1.1, respectively. The novel ratio of the H2Pc-CNT composite ingredients and comparably high value of the TCR make the devices attractive for bolometric applications meant to measure the intensity of infrared radiation. Moreover, given their easy fabrication and low-cost materials, the fabricated devices have great potential for commercialization.

Signal Transducer and Activator of Transcription 6 Changes and Protein Frustration by Single Amino Acid Substitutions: Implications for Cancer Progression.

Signal transducer and activator of transcription 6 (STAT6) is a multifunctional protein that plays critical functions in cell proliferation, apoptosis, differentiation, and angiogenesis. Mutations in STAT6 may contribute to the development of certain complex diseases such as cancer. This study examined single amino acid substitutions in STAT6 to pinpoint deleterious variants and their related structural and functional impairments. Data on STAT6 mutations were obtained from the Ensembl database and analyzed to evaluate the selected mutations for their pathogenicity and destabilizing or harmful effects. Specifically, we analyzed aggregation propensity, nonpacking density, and accessible surface area on the chosen mutations. The results suggest that seven out of eight mutations are less soluble, which might lead to aggregation, disrupt ordered helices, and alter strand propensity. Four mutations lay in the conserved regions of the protein, as revealed by the Consurf analysis. We found that three mutations, E318G, L365F, and R562H, change hydrophobic contacts and lead to frustration of STAT6, which can alter its stability, contributing to disease progression in cancer. In conclusion, these findings inform how single amino acid changes can destabilize STAT6. This has implications for cancer progression which warrants further experimental research.

Development of low-cost bacterial cellulose-pomegranate peel extract-based antibacterial composite for potential biomedical applications.

This study was aimed to develop low-cost bacterial cellulose (BC)-based antibacterial composite with pomegranate (Punica granatum L.) peel extract (PGPE) for potential biomedical applications. BC was cost-effectively produced by utilizing food wastes, and PGPE was ex situ impregnated into its hydrogel. Field-emission scanning electron microscopic (FE-SEM) observation showed a nanofibrous and microporous morphology of pristine BC and confirmed the development of BC-PGPE composite. Fourier transform infrared (FTIR) spectroscopy indicated the chemical interaction of PGPE with BC nanofibers. BC-PGPE composite held 97 % water of its dry weight and retained it for more than 48 h. The BC-PGPE composite exhibited better reswelling capabilities than pristine BC after three consecutive re-wetting cycles. The antibacterial activity of the BC-PGPE composite was determined via minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), disc diffusion, and plate count methods. The PGPE extract showed good antimicrobial activity against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative), both in the form of extract and composite with BC, with relatively better activity against the former. The BC-PGPE composite produced a 17 mm zone of inhibition against S. aureus, while no inhibition zone was formed against E. coli. Furthermore, BC-PGPE composite caused a 100 % and 50 % reduction in the growth of S. aureus and E. coli, respectively. The findings of this study indicate that BC-PGPE composite could be a promising antibacterial wound dressing material.

Microencapsulation of Lacticaseibacillus rhamnosus GG for Oral Delivery of Bovine Lactoferrin: Study of Encapsulation Stability, Cell Viability, and Drug Release.

Probiotics are delivered orally for treating gastrointestinal tract (GIT) infections; thus, they should be protected from the harsh environment of the GIT, such as through microencapsulation. Here, we microencapsulated cells of the probiotic Lacticaseibacillus rhamnosus GG via the liquid-droplet-forming method and evaluated them for oral delivery of bovine lactoferrin (bLf). Briefly, sodium alginate capsules (G-capsules) were first prepared, crosslinked with calcium chloride (C-capsules), and then modified with disodium hydrogen phosphate (M-capsules). All capsules showed good swelling behavior in the order of G-capsules > C-capsules > M-capsules in simulated gastric fluid (SGF, pH 2) and simulated intestinal fluid (SIF, pH 7.2). FE-SEM observations showed the formation of porous surfaces and successful microencapsulation of L. rhamnosus GG cells. The microencapsulated probiotics showed 85% and 77% viability in SGF and SIF, respectively, after 300 min. Compared to the 65% and 70% viability of gelation-encapsulated and crosslinking-encapsulated L. rhamnosus GG cells, respectively, the mineralization-encapsulated cells showed up to 85% viability after 300 min in SIF. The entrapment of bLf in the mineralization-encapsulated L. rhamnosus GG cells did not show any toxicity to the cells. FTIR spectroscopy confirmed the successful surface modification of L. rhamnosus GG cells via gelation, crosslinking, and mineralization, along with the entrapment of bLf on the surface of microencapsulated cells. The findings of these studies show that the microencapsulated L. rhamnosus GG cells with natural polyelectrolytes could be used as stable carriers for the oral and sustainable delivery of beneficial biotherapeutics without compromising their viability and the activity of probiotics.

Cost-Effective Synthesis of Bacterial Cellulose and Its Applications in the Food and Environmental Sectors.

Bacterial cellulose (BC), also termed bio-cellulose, has been recognized as a biomaterial of vital importance, thanks to its impressive structural features, diverse synthesis routes, high thermomechanical properties, and its ability to combine with multiple additives to form composites for a wide range of applications in diversified areas. Its purity, nontoxicity, and better physico-mechanical features than plant cellulose (PC) make it a better choice for biological applications. However, a major issue with the use of BC instead of PC for various applications is its high production costs, mainly caused by the use of expensive components in the chemically defined media, such as Hestrin-Schramm (HS) medium. Furthermore, the low yield of BC-producing bacteria indirectly accounts for the high cost of BC-based products. Over the last couple of decades, extensive efforts have been devoted to the exploration of low-cost carbon sources for BC production, besides identifying efficient bacterial strains as well as developing engineered strains, developing advanced reactors, and optimizing the culturing conditions for the high yield and productivity of BC, with the aim to minimize its production cost. Considering the applications, BC has attracted attention in highly diversified areas, such as medical, pharmaceutics, textile, cosmetics, food, environmental, and industrial sectors. This review is focused on overviewing the cost-effective synthesis routes for BC production, along with its noteworthy applications in the food and environmental sectors. We have made a comprehensive review of recent papers regarding the cost-effective production and applications of BC in the food and environmental sectors. This review provides the basic knowledge and understanding for cost-effective and scaleup of BC production by discussing the techno-economic analysis of BC production, BC market, and commercialization of BC products. It explores BC applications as food additives as its functionalization to minimize different environmental hazards, such as air contaminants and water pollutants.

Effect of Vibrations, Displacement, Pressure, Temperature and Humidity on the Resistance and Impedance of the Shockproof Resistors Based on Rubber and Jelly (NiPc-CNT-Oil) Composites.

Here, we present the design, fabrication and characterization of shockproof rubber-jelly (NiPc-CNT-oil) composite-based resistors. To fabricate the resistors, gels of CNT and NiPc with edible oil were prepared and deposited on a flexible rubber substrate using rubbing-in technique. The devices' resistance and impedance were investigated under the effect of pressure, displacement, humidity, temperature and mechanical vibrations. The resistance and the impedance decreased, on average, by 1.08 times under the effect of pressure (up to 850 gf/cm2) and by 1.04 times under the effect of displacement (up to 50 µm). Accordingly, upon increasing the humidity from 60% to 90% RH, the resistance and impedance decreased by up to 1.04 times, while upon increasing the temperature from 25 °C to 43 °C, the resistance and impedances also decreased by up to 1.05 times. Moreover, under the effect of vibration, a decrease in resistance and impedance, by up to 1.03 times, was observed. The investigated samples can potentially be used as prototypes for the development of shockproof jelly electronic-based devices in particular resistors. The technological achievement in the fabrication of these devices is the use of edible organic oil, which allows for the fabrication of uniform jelly films of organic materials that cannot be realized simply by mixing "dry" ingredients. Especially, we highlight that edible organic oil is environmentally friendly, unlike some other inorganic oils that are used in practice.

Alginate biopolymer as a reactor container for copper oxide-tin oxide: Efficient nanocatalyst for reduction of different pollutants.

The need of clean water demands to design an efficient catalytic system with high effective and selective reduction of water pollutants. Here, we successfully prepared copper oxide-tin oxide (CuO-SnO2) nanomaterial and further wrapped in Na-alginate hydrogel (Alg/CuO-SnO2). CuO-SnO2 and Alg/CuO-SnO2 were characterized by FESEM, EDS, FTIR-ATR, and XRD and tested for the reduction of water pollutants. The catalytic ability of CuO-SnO2 and Alg/CuO-SnO2 was examined for numerous pollutants like 4-nitrophenol (4-NP), methyl orange (MO), congo red (CR), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]) where the designed CuO-SnO2 and Alg/CuO-SnO2 nanocatalysts were most selective toward MB reduction. Further on optimization of catalyst amount, stability, and reducing agent amount, it was found that the increase of nanocatalyst amount and NaBH4 concentration increase the rate of MB reduction. CuO-SnO2 and Alg/CuO-SnO2 nanocatalysts reduced MB in 3.0 min with reaction rate constants (kapp) of 1.2944 min-1 and 1.2715 min-1, respectively. Additionally, Alg/CuO-SnO2 nanocatalyst was easily recovered by simply pulling hydrogel after completion of reaction and reused four times with no loss in efficiency. Besides, Alg/CuO-SnO2 nanocatalyst was further investigated in real samples like sea water, irrigation water, well water, university wastewater and found effective for MB reduction even in real samples.

Preparation, Characterization, and Biological Features of Cactus Coated Bacterial Cellulose Hydrogels.

The current study was aimed at developing BC-Cactus (BCC) composite hydrogels with impressive mechanical features for their potential applications in medical and environmental sectors. BCC composites hydrogels were developed through cactus gel coating on a never dried BC matrix. The FE-SEM micrographs confirmed the saturation of BC fibrils with cactus gel. Additionally, the presence of various functional groups and alteration in crystalline behavior was confirmed through FTIR and XRD analysis. Mechanical testing illustrated a three-times increase in the strain failure and an increase of 1.6 times in the tensile strength of BCC composite. Absorption capabilities of BCC were much higher than pure BC and it retained water for a longer period of time. Additionally, the rewetting and absorption potentials of composites were also higher than pure BC. The composite efficiently adsorbed Pb, Zn, Cu, and Co metals. Biocompatibility studies against human HaCat cell line indicated much better cell adhesion and proliferation of BCC compared to BC. These findings advocate that the BCC composite could find applications in medical, pharmaceutical and environmental fields.

Copper Oxide-Antimony Oxide Entrapped Alginate Hydrogel as Efficient Catalyst for Selective Reduction of 2-Nitrophenol.

Copper oxide-antimony oxide (Cu2O-Sb2O3) was prepared and entrapped inside Na-alginate hydrogel (Alg@Cu2O-Sb2O3). The developed Alg@Cu2O-Sb2O3 was used as catalytic reactor for the reduction of 4-nitrophenol (4-NP), 2-nitrophenol (2-NP), 2,6-dinitrophenol (2,6-DNP), methyl orange (MO), congo red (CR), acridine orange (AO), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]). Alg@Cu2O-Sb2O3 was found to be selective and more efficient for the reduction of 2-NP among all the pollutants. Therefore, 2-NP was selected for a detailed study to optimize various parameters, e.g., the catalyst amount, reducing agent concentration, 2-NP concentration and recyclability. Alg@Cu2O-Sb2O3 was found to be very stable and easily recyclable for the reduction of 2-NP. The Alg@Cu2O-Sb2O3 nanocatalyst reduced 2-NP in 1.0 min, having a rate constant of 3.8187 min-1.

Ultraviolet and Infrared Irradiations Sensing of Gel-Orange Dye Composite-Based Flexible Electrochemical Cells.

The flexible and shockproof rubber-based Al/OD-Gel/Cu electrochemical cell was designed, fabricated, and investigated for the detection of IR and UV irradiations. For this purpose, the transparent gel-orange dye composite was deposited on the porous rubber substrate between aluminum and copper electrodes. It was observed that the gel-orange dye composite was mechanically like a gel: soft and flexible. Electrically, this composite (gel-orange dye) forms a flexible electrolyte. It was found that the impedance of the samples under the effect of infrared irradiation decreased by 2.02 to 2.19 times on changing frequency from 100 Hz to 200 kHz. Accordingly, under the effect of ultraviolet irradiation, the impedance of the samples decreased by 1.23 to 1.45 times on increasing frequency from 100 Hz to 200 kHz. Under the effect of infrared irradiation up to 4000 W/m2, the cell's open-circuit voltage increased by 1.59 times. The cell's open-circuit voltage also increased by 1.06 times under the effect of ultraviolet irradiation up to 200 uW/cm2. The mechanism of the absorption of the infrared and ultraviolet irradiations by the OD-Gel composite has been discussed in detail. The fabricated flexible rubber substrate-based Al/OD-Gel/Cu electrochemical cells can be used as a prototype for the development of gel electronics-based devices.

Nanoarchitectured Cu based catalysts supported on alginate/glycyl leucine hybrid beads for tainted water treatment.

Water pollution reached worrying point due to different dye pollutants which demands an instant solution. One of the best ways to manage water pollutants is their reduction and decolorization to less-toxic and useful compounds. However, reduction process requires an effective, stable, and recyclable catalyst to reduce such pollutants more effectively. Metal nanoparticles (M0) are highly effective catalysts but separation of nanoparticles after reaction is difficult and requires a high-speed centrifugation. If loaded on polymer-beads, they can be easily separated from the reaction-mixture. Hearin, alginate/glycyl leucine (AGL) hybrid-beads were prepared, and copper nanoparticles (Cu0) were grown on it by simple process. M0/AGL bead catalysts were tested toward reducing various toxic compounds. Among all developed composite-beads, the catalytic performance of Cu0/AGL was highest in terms of reduction kinetics. After initial screening for different pollutants, Cu0/AGL was much more effective for MO reduction, thus, all optimized different parameters i.e., catalyst dosage, stability, amount of reducing-agent and recyclability were experimentally determined. The Cu0/AGL showed high-rate constants (kapp) of 0.7566 and 2.9506 min-1 depending on beads content. The reusability of the Cu0/AGL catalysts up to the 7th cycle has been checked. With the use of AGL as support for the Cu nanoparticles, not only the catalytic activity was retained for longer times during reusability, but it helped in their easy separation.