Liquid phase selective oxidation of veratryl alcohol to veratraldehyde using pure and Mg-doped copper chromite catalysts

Mg-doped copper chromite (CuCr2O4) nanocomposites were synthesised through conventional technique. The pure and doped CuCr2-xMgx O4 (x = 0.00-0.1, 0.2 and 0.3%) nanocomposites were characterized in terms of their morphology, crystal structure, surface area and catalytic performance. The chemical composition of CuCr2-xMgx O4 was confirmed via FT-IR. The formation of pure and doped catalysts was validated by XRD results. TEM/SEM confirmed the formation of CuCr2-xMgxO4 nanoparticles. Mg-doped samples possess a high specific surface area compared to pure CuCr2O4. Thus, the effects of temperature, solvent, time, oxidant and the amount of catalyst on the oxidation of veratryl alcohol were reported. Furthermore, detailed mechanisms of the catalytic oxidation of veratryl alcohol as well as the reusability and stability of the nanomaterial were investigated. The resulting composites were shown to be effective heterogeneous catalysts for the oxidation of veratryl alcohol.

Green synthesis of ZnO-TiO2/RGO nanocomposites using Senna surattensis extract: a novel approach for enhanced anticancer efficacy and biocompatibility

The purpose of the present study is to enhance the anticancer and biocompatibility performance of TiO2 NPs, ZnO NPs, ZnO-TiO2 (NCs), and ZnO-TiO2/reduced graphene oxide (RGO) NCs against two types of human cancer (HCT116) and normal (HUVCE) cells. A novel procedure for synthesizing ZnO-TiO2/RGO NCs has been developed using Senna surattensis extract. The improved physicochemical properties of the obtained samples were investigated using different techniques such as XRD, TEM, SEM, XPS, FTIR, DLS and UV-visible spectroscopy. XRD results showed that the addition of ZnO and RGO sheets affects the crystal structure and phase of TiO2 NPs. SEM and TEM images displayed that the TiO2 NPs and ZnO NPs were small with uniform spherical morphology in the prepared ZnO-TiO2/RGO NCs. Besides, it is shown that ZnO-TiO2 NCs anchored onto the surface of RGO sheets with a particle size of 14.80 ± 0.5 nm. XPS data confirmed the surface chemical composition and oxidation states of ZnO-TiO2/RGO NCs. Functional groups of prepared NPs and NCs were determined using FTIR spectroscopy. DLS data confirmed that the addition of ZnO and RGO sheets improves the negative surface charge of the prepared pure TiO2 NPs (-22.51 mV), ZnO NPs (-18.27 mV), ZnO-TiO2 NCs (-30.20 mV), and ZnO-TiO2/RGO NCs (-33.77 mV). Optical analysis exhibited that the bandgap energies of TiO2 NPs (3.30 eV), ZnO NPs (3.33 eV), ZnO-TiO2 NCs (3.03 eV), and ZnO-TiO2/RGO NCs (2.78 eV) were further enhanced by adding ZnO NPs and RGO sheets. This indicates that the synthesized samples can be applied to cancer therapy and environmental remediation. The biological data demonstrated that the produced ZnO-TiO2/RGO NCs show a more cytotoxic effect on HCT116 cells compared to pure TiO2 NPs and ZnO-TiO2 NCs. On the other hand, these NCs displayed the lowest level of toxicity towards normal HUVCE cells. These results indicate that the ZnO-TiO2/RGO NCs have strong toxicity against HCT116 cells and are compatible with normal cells. Our results show that the plant extract enhanced the physicochemical properties of NPs and NCs compared with the traditional chemical methods for synthesis. This study could open new avenues for developing more effective and targeted cancer treatments.

The Catalytic Role of Superparamagnetic Iron Oxide Nanoparticles as a Support Material for TiO2 and ZnO on Chlorpyrifos Photodegradation in an Aqueous Solution

Chlorpyrifos (CP) is a globally used pesticide with acute toxicity. This work studied the photocatalytic degradation of CP using TiO2, ZnO nanoparticles, and nanocomposites of TiO2 and ZnO supported on SPIONs (SPION@SiO2@TiO2 and SPION@SiO2@ZnO). The nanocomposites were synthesized by multi-step incipient wetness impregnation. The effects of the initial pH, catalyst type, and dose were evaluated. The nanocomposites of SPION@SiO2@TiO2 and SPION@SiO2@ZnO showed higher CP photodegradation levels than free nanoparticles, reaching 95.6% and 82.3%, respectively, at pH 7. The findings indicate that iron oxide, as a support material for TiO2 and ZnO, extended absorption edges and delayed the electron-hole recombination of the nanocomposites, improving their photocatalytic efficiency. At the same time, these nanocomposites, especially SPION@SiO2@TiO2, showed efficient degradation of 3,5,6-trichloropyridinol (TCP), one of the final metabolites of CP. The stability and reuse of this nanocomposite were also evaluated, with 74.6% efficiency found after six cycles. Therefore, this nanomaterial represents an eco-friendly, reusable, and effective alternative for the degradation of chlorpyrifos in wastewater treatment.

Multifunctional ternary ZnMgFe LDH as an efficient adsorbent for ceftriaxone sodium and antimicrobial agent: sustainability of adsorption waste as a catalyst for methanol electro-oxidation

In order to achieve sustainable benefits for the adsorption of wastewater pollutants, spent adsorbents need to be recycled and/or valorized. This work studied a two-dimensional (2D) ZnMgFe layered double hydroxide (LDH) for ceftriaxone sodium (CTX) adsorption. This LDH showed a crystallite size of 9.8 nm, a BET surface area of 367.59 m2 g-1, and a micro-sphere-like morphology. The factors investigated in this study were the adsorbent dose, initial concentration, initial pH, and contact time. ZnMgFe LDH showed 99% removal of CTX with a maximum adsorption capacity of 241.75 mg g-1 at pH = 5. The Dubinin-Radushkevich model was found to be the most adequate isotherm model. The spent adsorbent (ZnMgFe LDH/CTX) was reused as an electro-oxidation catalyst for direct methanol fuel cells. ZnMgFe LDH/CTX showed almost a 10-fold increase in electrochemical activity for all scan rates compared to bare ZnMgFe LDH in 1 M KOH. As methanol concentration increases, the maximum current density generated by both the ZnMgFe LDH and ZnMgFe LDH/CTX samples increases. Moreover, the maximum current density for ZnMgFe LDH/CTX was 47 mA cm-2 at a methanol concentration of 3 M. Both samples possess reasonable stability over a 3600 S time window with no significant deterioration of electrochemical performance. Moreover, the antimicrobial studies showed that ZnMgFe LDH had a significant antifungal (especially Aspergillus, Mucor, and Penicillium species) and antibacterial (with greater action against Gram-positive than negative) impact on several severe infectious diseases, including Aspergillus. This study paves the way for the reuse and valorization of selected adsorbents toward circular economy requirements.

Transition metal-based nanoparticles as potential antimicrobial agents: recent advancements, mechanistic, challenges, and future prospects

Bacterial transmission is considered one of the potential risks for communicable diseases, requiring promising antibiotics. Traditional drugs possess a limited spectrum of effectiveness, and their frequent administration reduces effectiveness and develops resistivity. In such a situation, we are left with the option of developing novel antibiotics with higher efficiency. In this regard, nanoparticles (NPs) may play a pivotal role in managing such medical situations due to their distinct physiochemical characteristics and impressive biocompatibility. Metallic NPs are found to possess extraordinary antibacterial effects that are useful in vitro as well as in vivo as self-modified therapeutic agents. Due to their wide range of antibacterial efficacy, they have potential therapeutic applications via diverse antibacterial routes. NPs not only restrict the development of bacterial resistance, but they also broaden the scope of antibacterial action without binding the bacterial cell directly to a particular receptor with promising effectiveness against both Gram-positive and Gram-negative microbes. This review aimed at exploring the most relevant types of metal NPs employed as antimicrobial agents, particularly those based on Mn, Fe, Co, Cu, and Zn metals, and their antimicrobial mechanisms. Further, the challenges and future prospects of NPs in biological applications are also discussed.

Catalytic dye degradation by novel phytofabricated silver/zinc oxide composites

Phytofabrication of the nanoparticles with exotic shape and size is an attractive area where nanostructures with noteworthy physicochemical and optoelectronic properties that can be significantly employed for photocatalytic dye degradation. In this study a medicinal plant, Plumbago auriculata leaf extract (PALE) was used to synthesize zinc oxide particles (ZnOPs) and silver mixed zinc oxide particles (ZnOAg1Ps, ZnOAg10Ps, ZnO10Ag1Ps) by varying the concentration of the metal precursor salts, i.e. zinc acetate and silver nitrate. The PALE showed significantly high concentrations of polyphenols, flavonoids, reducing sugar, starch, citric acid and plumbagin up to 314.3 ± 0.33, 960.0 ± 2.88, 121.3 ± 4.60, 150.3 ± 3.17, 109.4 ± 2.36, and 260.4 ± 8.90 μg/ml, respectively which might play an important role for green synthesis and capping of the phytogenic nanoparticles. The resulting particles were polydispersed which were mostly irregular, spherical, hexagonal and rod like in shape. The pristine ZnOPs exhibited a UV absorption band at 352 nm which shifted around 370 in the Ag mixed ZnOPs with concomitant appearance of peaks at 560 and 635 nm in ZnO10Ag1Ps and ZnOAg1Ps, respectively. The majority of the ZnOPs, ZnOAg1Ps, ZnOAg10Ps, and ZnO10Ag1Ps were 407, 98, 231, and 90 nm in size, respectively. Energy dispersive spectra confirmed the elemental composition of the particles while Fourier transform infrared spectra showed the involvement of the peptide and methyl functional groups in the synthesis and capping of the particles. The composites exhibited superior photocatalytic degradation of methylene blue dye, maximum being 95.7% by the ZnOAg10Ps with a rate constant of 0.0463 s−1 following a first order kinetic model. The present result clearly highlights that Ag mixed ZnOPs synthesized using Plumbago auriculata leaf extract (PALE) can play a critical role in removal of hazardous dyes from effluents of textile and dye industries. Further expanding the application of these phytofabricated composites will promote a significant complementary and alternative strategy for treating refractory pollutants from wastewater.

Potato Starch-sodium Alginate-Zr (IV) Phosphate Bio-nanocomposite Ion Exchanger: Synthesis, Characterization and Environmental Application

Background:

The introduction of inorganic fillers into the polymer matrix (with multiplicity in functionalization) augments the specific properties of such materials. One such method employed here, which is environmental friendly and facile is the sol-gel synthesis

Objective:

The nanocomposite synthesized by the above mentioned method was primarily utilized for ion-exchange applications in general and cation exchange in particular. The ZrP based nanocomposite (PS/AG/ZrP) has been examined (as a photocatalyst) for the elimination of toxic cationic dye, methylene blue (Mb) from the wastewater by the mechanism of photodegradation. This study provides the experimental evidence and discussion of the different physicochemical characteristics of the synthesized nanocomposite

Method:

Herein, we synthesized zirconium phosphate (ZrP)-linked-potato starch/sodium alginate nanocomposite ion exchanger (PS/AG/ZrP) employing facile sol-gel method. Highly sophisticated techniques like FTIR, TGA, SEM, TEM, XRD & UV-Vis were subjected to characterize the PS/AG/ZrP nanocomposite

Results:

The ion exchange (IE) results show that the nanocomposite ion exchanger (PS/AG/ZrP-6) exhibited higher IEC (2.1meq/g) and thermal stability as conferred from IEC and TGA studies. Using UV-Vis irradiation, photocatalytic results revealed that 74.5% of Mb dye was degraded by novel nanocomposite (PS/AG/ZrP) within 50 minutes.

Conclusion:

The results discussed reveal that the nanocomposite (PS/AG/ZrP-6) is a potential candidate for ion exchange applications vis-à-vis a photocatalyst for the remediation of wastewater as the time demands. The nanocomposite (PS/AG/ZrP-6) successfully characterized through various techniques and utilized as a potential ion exchanger and a photocatalyst for the dye degradation (MB) under UV-Vis irradiation

Water Pollutants p-Cresol Detection Based on Au-ZnO Nanoparticles Modified Tapered Optical Fiber

In this work, a localized plasmon-based sensor is developed for para-cresol (p-cresol) - a water pollutant detection. A nonadiabatic [Formula: see text] of tapered optical fiber (TOF) has been experimentally fabricated and computationally analyzed using beam propagation method. For optimization of sensor's performance, two probes are proposed, where probe 1 is immobilized with gold nanoparticles (AuNPs) and probe 2 is immobilized with the AuNPs along with zinc oxide nanoparticles (ZnO-NPs). The synthesized metal nanomaterials were characterized by ultraviolet-visible spectrophotometer (UV-vis spectrophotometer) and transmission electron microscope (HR-TEM). The nanomaterials coating on the surface of the sensing probe were characterized by a scanning electron microscope (SEM). Thereafter, to increase the specificity of the sensor, the probes are functionalized with tyrosinase enzyme. Different solutions of p-cresol in the concentration range of [Formula: see text] - [Formula: see text] are prepared in an artificial urine solution for sensing purposes. Different analytes such as uric acid, β -cyclodextrin, L-alanine, and glycine are prepared for selectivity measurement. The linearity range, sensitivity, and limit of detection (LOD) of probe 1 are [Formula: see text] - [Formula: see text], 7.2 nm/mM (accuracy 0.977), and [Formula: see text], respectively; and for probe 2 are [Formula: see text] - [Formula: see text], 5.6 nm/mM (accuracy 0.981), and [Formula: see text], respectively. Thus, the overall performance of probe 2 is quite better due to the inclusion of ZnO-NPs that increase the biocompatibility of sensor probe. The proposed sensor structure has potential applications in the food industry and clinical medicine.

Chemically synthesized (Ag, Mn2O3)-codecorated ZnO nanoparticles for achieving superior visible light-induced photodegradation and enhanced gas sensing activity

Heterostructural engineering and noble metal coupling are effective strategies to optimize semiconductor photocatalytic materials. In this work, (Ag, Mn2O3)-codecorated ZnO nanoparticles with different Mn2O3 contents (0-10 mol%) were synthesized by integrating the two strategies by a facile two-step polymer network-gel process. The photocatalytic activity of Ag/ZnO (AZM0) was significantly enhanced with the optimum Mn2O3 molar ratio of 3 mol%. The degradation efficiency of AZM3 is ∼3 times and ∼4.8 times higher than that of AZM0 for the degradation of methylene blue (MB) upon exposure to simulated sunlight and visible light, respectively. Also, this ternary nanocomposite exhibits enhanced gas sensing performance towards NO2 under ultraviolet/visible light irradiation at room temperature. The analysis of its microstructural, optical and photoelectrical characteristics suggests the synergistic coupling effects of Ag and Mn2O3, in which the significantly enhanced visible light response and hetero-interface charge carrier migration are the critical factors for the improvement of photocatalytic efficiency and gas sensing activity. Furthermore, the effects of recycling ability, the influence of the initial solution pH, the catalyst dosage and the main active species during the catalysis process on photocatalytic activity were explored. This study develops a feasible pathway to consciously construct multiheterostructures for enhancing the photocatalytic activity with great potential applications in toxic pollution abatement and noxious gas detection.

Metal/metal oxide nanocomposites for bactericidal effect: A review

Many microbial species causing infectious disease all over the world became a social burden and creating threat among community. These microbes possess long lifetime, enhancing mortality and morbidity rate in affected organisms. In this condition, the treatment was ineffective and more chances of spreading of infection into other organisms. Hence, it is necessary to initiate infection control efforts and prevention activities against multidrug resistant microbes, to reduce the death rate of people. Seriously concerning towards this problem progress was shown in developing significant drugs with least side effects. Emergence of nanoparticles and its novelty showed effective role in targeting and destructing microbes well. Further, many research works have shown nanocomposites developed from nanoparticles coupled with other nanoparticles, polymers, carbon material acted as an exotic substance against microbes causing severe loss. However, metal and metal oxide nanocomposites have gained interest due to its small size and enhancing the surface contact with bacteria, producing damage to it. The bactericidal mechanism of metal and metal oxide nanocomposites involve in the production of reactive oxygen species which includes superoxide radical anions, hydrogen peroxide anions and hydrogen peroxide which interact with the cell wall of bacteria causing damage to the cell membrane in turn inhibiting the further growth of cell with leakage of internal cellular components, leading to death of bacteria. This review provides the detailed view on antibacterial activity of metal and metal oxide nanocomposite which possessed novelty due to its physiochemical changes.

Cobalt doped nano-hydroxyapatite incorporated gum tragacanth-alginate beads as angiogenic-osteogenic cell encapsulation system for mesenchymal stem cell based bone tissue engineering

Angiogenic-osteogenic cell encapsulation system is a technical need for human mesenchymal stem cell (hMSC)-based bone tissue engineering (BTE). Here, we have developed a highly efficient hMSC encapsulation system by incorporating bivalent cobalt doped nano-hydroxyapatite (HAN) and gum tragacanth (GT) as angiogenic-osteogenic components into the calcium alginate (CA) beads. Physico-chemical characterizations revealed that the swelling and degradation of HAN incorporated CA-GT beads (GT-HAN) were 1.34 folds and 2 folds higher than calcium alginate (CA) beads. Furthermore, the diffusion coefficient of solute molecule was found 2.5-fold higher in GT-HAN with respect to CA bead. It is observed that GT-HAN supports the long-term viability of encapsulated hMSC and causes 50% less production of reactive oxygen species (ROS) in comparison to CA beads. The expression of osteogenic differentiation markers was found 1.5-2.5 folds higher in the case of GT-HAN in comparison to CA. A similar trend was observed for hypoxia inducible factor 1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF). The soluble secretome from hMSC encapsulated in the GT-HAN induced proliferation of endothelial cells and supported tube formation (2.5-fold higher than CA beads). These results corroborated that GT-HAN could be used as an angiogenic-osteogenic cell encapsulation matrix for hMSC encapsulation and BTE application.

Lignin peroxidase in focus for catalytic elimination of contaminants - A critical review on recent progress and perspectives

Lignin peroxidase (LiP) seems to be a catalyst for cleaving high-redox potential non-phenolic compounds with an oxidative cleavage of CC and COC bonds. LiP has been picked to seek a practical and cost-effective alternative to the sustainable mitigation of diverse environmental contaminants. LiP has been an outstanding tool for catalytic cleaning and efficient mitigation of environmental pollutants, including lignin, lignin derivatives, dyes, endocrine-disrupting compounds (EDCs), and persistent organic pollutants (POPs) for the past couple of decades. The extended deployment of LiP has proved to be a promising method for catalyzing these environmentally related hazardous pollutants of supreme interest. The advantageous potential and capabilities to act at different pH and thermostability offer its working tendencies in extended environmental engineering applications. Such advantages led to the emerging demand for LiP and increasing requirements in industrial and biotechnological sectors. The multitude of the ability attributed to LiP is triggered by its stability in xenobiotic and non-phenolic compound degradation. However, over the decades, the catalytic activity of LiP has been continuing in focus enormously towards catalytic functionalities over the available physiochemical, conventional, catalyst mediated technology for catalyzing such molecules. To cover this literature gap, this became much more evident to consider the catalytic attributes of LiP. In this review, the existing capabilities of LiP and other competencies have been described with recent updates. Furthermore, numerous recently emerged applications, such as textile effluent treatment, dye decolorization, catalytic elimination of pharmaceutical and EDCs compounds, have been discussed with suitable examples.

Bifunctional PVA/ZnO/AgI/Chlorophyll Nanocomposite Film: Enhanced Photocatalytic Activity for Degradation of Pollutants and Antimicrobial Property under Visible-Light Irradiation

Here, poly(vinyl alcohol) (PVA) with numerous hydroxyl groups has been applied as a suitable substrate for efficient formation of zinc oxide (ZnO) nanoparticles with a flower shape (confirmed by electron-scanning microscopy), silver iodide (AgI) nanoparticles, and chlorophyll (Chl), as a natural-based photocatalyst (PVA/ZnO/AgI/Chl). First, an efficient preparation route for the PVA/ZnO/AgI/Chl nanophotocatalyst is presented starting from the extraction of Chl from fresh spinach. Then, the catalytic role of the prepared composite is precisely investigated in degradation of methylene blue (MB). The effects of visible-light irradiation, different contact times, and the employed ingredients on the architecture of the PVA/ZnO/AgI/Chl are screened in the degradation process of MB. It is demonstrated that the best result (MB removal efficiency ca. 95.5%) is achieved by applying the visible-light irradiation using a LED lamp (70 W, λ = 425 nm) for a 60 min duration. Moreover, the photocatalytic performance of PVA/ZnO/AgI/Chl has been further confirmed by degradation of Congo red (CR) (ca. 92%, in 150 min) and 4-chlorophenol (4-CP) (88%, in 270 min), as well. As another function of the prepared PVA/ZnO/AgI/Chl composite, a substantial antibacterial property against human bacterial pathogens such as Staphylococcus aureus and Escherichia coli as Gram-positive and Gram-negative bacteria has been noticed, studied by agar diffusion cup plate and colony methods. The zones of inhibition have been evaluated ca. 20 and 12 mm for the S. aureus and E. coli cell lines, respectively. Finally, a great synergy between the prepared composite and the visible light has been observed through the examination of the live bacteria: 99.6% for S. aureus and 99.8% for E. coli in the presence of visible light, after the subjection of PVA/ZnO/AgI/Chl particles to the bacteria, verified by the colony counter method.

A Simple Method for Developing a Hand-Drawn Paper-Based Sensor for Mercury; Using Green Synthesized Silver Nanoparticles and Smartphone as a Hand-Held-Device for Colorimetric Assay

Mercury ions are highly toxic at trace levels, and its pollution has posed a significant threat to the environment and public health, where current detection methods mainly require laborious operation and expensive instrumentation. Herein, a simple, cost-effective, instrument-free approach for selective detection of Hg2+ based on a hand-drawn paper-based naked-eye colorimetric device is developed. To develop a hand-drawn paper-based device, a crayon is used to build hydrophobic barriers and a paper puncher is applied to obtain patterns as a sensing zone. A green method for the synthesis of silver nanoparticles (AgNPs) is applied using Achillea Wilhelmsii (Aw) extract. The sensing ability of Aw-AgNPs toward Hg2+ is investigated in both solution-phase and paper substrate loaded with Aw-AgNPs using colorimetric methods. For the paper-based sensor, the quantification of the target relies on the visual readout of a color-changed sensing zone modified with Aw-AgNPs. Under optimal conditions, the color of Aw-AgNPs in aqueous solution and on the coated paper substrate can change from brown to colorless upon addition of target, with a detection limit of 28 × 10-9 m and 0.30 × 10-6 m, respectively. In conclusion, the present study indicates the potential of this hand-drawn eco-friendly paper-based sensor for monitoring of mercury.

Matrix-dispersed PEI-coated SPIONs for fast and efficient removal of anionic dyes from textile wastewater samples: Applications to triphenylmethanes

Textile industries produce a massive amount of wastewater that should be cleaned from toxic substances such as fats, colors and any chemicals used during the production steps. Water-treatment methods should be facile, economic, fast and efficient. Here, we report the synthesis, characterization and application of matrix-dispersed superparamagnetic iron oxide nanoparticles (SPIONs) for the removal of anionic dyes from wastewater released from textile industrial plants. The matrix-dispersed SPIONs were synthesized via a solvothermal method in which a polyethyleneimine (PEI) shell was deposited onto SPIONs in order to add positive charges to their surfaces. TEM images revealed that the size of PEI-coated and uncoated SPIONs is 30-50 and 15-30 nm, respectively. Moreover, TEM images depicted that the as synthesized PEI-coated SPIONs show matrix-dispersed structures. Furthermore, the particle size obtained with DLS measurements was found to be 87.93 and 158.9 nm for uncoated and PEI-coated SPIONs, respectively. Bromophenol blue (BPB) and bromocresol green (BCG), two triphenylmethanes, were used as model anionic dyes. FTIR spectroscopy revealed the interaction between the PEI surface coating and the anionic dyes. The apparent ζ-potential measurements showed that the surface negative charges decreased from -13.5 to -4.03 mV upon coating with PEI. In order to investigate the anionic dyes removal/entrapment efficiency of SPIONs, a new derivative visible spectrophotometric method was developed for the simultaneous quantification of BPB and BCG before and after treatment where the linear ranges were 6.98-27.9 and 6.70-26.8 μg/mL and the recovery values were in the ranges of 98.10-101.7% and 99.55-104.8% for BCG and BPB, respectively. It was found that the uptake/adsorption capacity of PEI-coated SPIONs is ca.15.5 and 11.3 mg/g for BCG and BPB, respectively. The calculated thermodynamic parameters for the adsorption of BCG (ΔH = 37.08 J/mol and ΔS = 120.89 J/mol K) and BPB (ΔH = 181.26 J/mol and ΔS = 596.46 J/mol K) and the negative ΔG values indicate that the adsorption is thermodynamically favored. The adsorption processes were found to follow the pseudo-second-order kinetic model with r² values of 0.9982 and 0.9956 for BCG and BPB, respectively.

A review on analytical methods with special reference to electroanalytical methods for the determination of some anticancer drugs in pharmaceutical and biological samples

It is widely accepted that cancer, the second leading cause of death, is a morbidity with big impacts on the global health. In the last few years, chemo-therapeutic treatment continually induces alone most lengthy consequents, which is extremely harmful for the physiological and psychological health of the patients. In the present research, we discuss the recent techniques for employed for extraction, and quantitative determination of such compounds in pharmaceutical, and biological specimens. In the frame of this information, this review aims to provide basic principles of chromatography, spectroscopy, and electroanalytical methods for the analysis of anticancer drugs published in the last three years. The review also describes the recent developments regarding enhancing the limit of detection (LOD), the linear dynamic range, and so forth. The results show that the LOD for the chromatographic techniques with the UV detector was obtained equaled over the range 2.0 ng mL^-1-0.2 μg mL^-1, whereas the LOD values for analysis by chromatographic technique with the mass spectrometry (MS) detector was found between 10.0 pg mL^-1-0.002 μg mL^-1. The biological fluids could be directly injected to capillary electrophoresis (CE) in cases where the medicine concentration is at the contents greater than mg L^-1 or g L^-1. Additionally, electrochemical detection of the anticancer drugs has been mainly conducted by the voltammetry techniques with diverse modified electrodes, and lower LODs were estimated between 3.0 ng mL^-1-0.3 μg mL^-1. It is safe to say that the analyses of anticancer drugs can be achieved by employing a plethora of techniques such as electroanalytical, spectroscopy, and chromatography techniques.

Zinc oxide and zinc oxide-based nanostructures: biogenic and phytogenic synthesis, properties and applications

Zinc oxide nanoparticles (ZnO NPs) are considered as very significant and essential material due to its multifunctional properties, stability, low cost and wide usage. Many green and biogenic approaches for ZnO NPs synthesis have been reported using various sources such as plants and microorganisms. Plants contain biomolecules that can act as capping, oxidizing and reducing agents that increase the rate of reaction and stabilizes the NPs. This review emphasizes and compiles different types of plants and parts of plant used for the synthesis of ZnO and its potential applications at one place. The influence of biogenic and phytogenic synthesized ZnO on its properties and possible mechanisms for its fabrication has been discussed. This review also highlights the potential applications and future prospects of phytogenic synthesized ZnO in the field of energy production and storage, sun light harvesting, environmental remediation, and biological applications.

Coupled with EDDS and approaching anode technique enhanced electrokinetic remediation removal heavy metal from sludge

In this work, the novel technology was used to remove heavy metal from sludge. The coupled with biodegradable ethylenediamine disuccinic acid (EDDS) and approaching anode electrokinetic (AA-EK) technique was used to enhance heavy metal removing from sludge. Electric current, sludge and electrolyte characteristics, heavy metal removal efficiency and residual content distribution, and heavy metal fractions percentage of variation were evaluated during the electrokinetic remediation process. Results demonstrated that the coupled with EDDS and AA-EK technique obtain a predominant heavy metal removal efficiency, and promote electric current increasing during the enhanced electrokinetic remediation process. The catholyte electrical conductivity was higher than the anolyte, and electrical conductivity of near the cathode sludge achieved a higher value than anode sludge during the coupled with EDDS and AA-EK remediation process. AA-EK technique can produce a great number of H⁺, which caused the sludge acidification and pH decrease. Cu, Zn, Cr, Pb, Ni and Mn obtain the highest extraction efficiency after the coupled with EDDS and AA-EK remediation, which were 52.2 ± 2.57%, 56.8 ± 3.62%, 60.4 ± 3.62%, 47.2 ± 2.35%, 53.0 ± 3.48%, 54.2 ± 3.43%, respectively. Also, heavy metal fractions analysis demonstrated that the oxidizable fraction percentage decreased slowly after the coupled with EDDS and AA-EK remediation.

Conventional and Nanotechnology-Based Sensing Methods for SARS Coronavirus (2019-nCoV)

Ongoing pandemic coronavirus (COVID-19) has affected over 218 countries and infected 88,512,243 and 1,906,853 deaths reported by Jan. 8, 2021. At present, vaccines are being developed in Europe, Russia, USA, and China, although some of these are in phase III of trials, which are waiting to be available for the general public. The only option available now is by vigorous testing, isolation of the infected cases, and maintaining physical and social distances. Numerous methods are now available or being developed for testing the suspected cases, which may act as carriers of the virus. In this review, efforts have been made to discuss the conventional as well as fast, rapid, and efficient testing methods developed for the diagnosis of 2019-nCoV.Testing methods can be based on the sensing of targets, which include RNA, spike proteins and antibodies such as IgG and IgM. Apart from the development of RNA targeted PCR, antibody and VSV pseudovirus neutralization assay along with several other diagnostic techniques have been developed. Additionally, nanotechnology-based sensors are being developed for the diagnosis of the virus, and these are also discussed.

Synthesis and photocatalytic activity of porous ZnO stabilized by TiO2 and Fe3O4 nanoparticles: investigation of pesticide degradation reaction in water treatment

The present research studies the photocatalytic degradation of a pesticide using TiO₂ and Fe₃O₄ nanoparticles supported on ZnO mesoporous (mZnO) substrate. Chlorpyrifos is an organophosphate pesticide with a C₉H₁₁Cl₃NO₃PS chemical formula. It is broadly utilized in agricultural fields to control product pests. The chlorpyrifos toxicity is acute and still dangerous to any aquatic organisms. The mZnO/TiO₂-Fe₃O₄ material was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and N₂ adsorption and desorption (Brunauer-Emmett-Teller; BET). In order to optimize three important operating parameters, i.e., chlorpyrifos concentration, mZnO/TiO₂-Fe₃O₄ nanocomposite amount, and pH, for photocatalytic degradation of chlorpyrifos, response surface methodology (RSM) was applied. The central composite design (CCD) including 20 experiments was used to conduct experiments. The highest photodegradation performance of about 94.8% was obtained for a chlorpyrifos concentration of 8 ppm, a pH of 10, and an amount of mZnO/TiO₂-Fe₃O₄ nanocomposite of 60 mg. The degradation of chlorpyrifos using mZnO/TiO₂-Fe₃O₄ presented good performance (more than 94%). The photocatalytic reaction followed pseudo-first-order kinetics with a rate constant of 0.058 min^-1 for chlorpyrifos degradation. The results propose that mZnO/TiO₂-Fe₃O₄ nanocomposite is a suitable alternative for the degradation of chlorpyrifos in aqueous solution. The improved photocatalytic efficiency could be attributed to the effective separation of electron-hole pairs via a Z-scheme mechanism.

Kinetic and thermodynamic studies of novel acid phosphates extracted from Cichorium intybus seedlings

Herein for the first time a novel acid phosphatase from the seedlings of Cichorium intybus was purified to homogeneity by using various chromatographic techniques (salt precipitation, ion exchange, size exclusion and affinity chromatography) and thermodynamically characterized. The molecular mass of purified enzyme (66 kDa) was determined by SDS-PAGE under denaturing and non-denaturing conditions and by gel-filtration confirmed as dimer of molecular mass 130 kDa. The Michaelis-Menten (Km) constant for -p-NPP (0.3 mM) and (7.6 μmol/min/mg) Vmax. The enzyme was competitively inhibited by phosphate, molybdate and vanadate. Phenyl phosphate, ɑ and β-glycero-phosphate and-p-NPP were found to be good substrate. When temperature increased from (55 °C to 75 °C), the deactivation rate constant (kd) was increased (0.1 to 4.6 min-1) and half- life was decreased from 630 min to 15 min. Various thermal denaturation parameters; change in enthalpy (ΔH°), change in entropy (ΔS°) and change in free energy (ΔG°) were found 121.93 KJ·mol-1, 72.45 KJ·mol-1 and 98.08 KJ·mol-1 respectively, confirming that acid phosphatase undergoes a significant process of unfolding during deactivation. The biochemical properties of acid phosphatase from C. intybus on the behalf of biological activity and its relationship to pH variations, thermal deactivation and kinetics parameters provide an insight into its novel features.

Synthesis of Poly(vinyl alcohol)-Aided ZnO/Mn2O3 Nanocomposites for Acid Orange-8 Dye Degradation: Mechanism and Antibacterial Activity

Zinc oxide is one of the novel metal oxides utilized for diverse applications. The sol-gel and unintended self-propagation procedures were applied to synthesize the porous and high surface area ZnO-based metal oxide nanocomposite. The p-type manganese(III) oxide was successfully coupled with n-type ZnO. The physical property characterization results revealed the surface area, porosity, and charge transfer capability improvement on the poly(vinyl alcohol) (PVA)-aided binary nanocomposite (PVA-ZnO/Mn2O3), compared to ZnO. The XRD patterns and TEM image analysis validated the nanometer size range for the materials (15-60 nm). The SEM micrographs and BET spectral details have confirmed the porous nature of the PVA-ZnO/Mn2O3 nanocomposite. The supporting results were obtained from the HRTEM (IFFT) and SAED pattern analyses. The EDX and HRTEM analyses were used for the confirmation of elemental composition and reality of the PVA-ZnO/Mn2O3 composite, respectively. The presence of the improved charge transfer property for PVA-ZnO/Mn2O3, compared to ZnO, was evidenced from acid orange-8 dye degradation. The highest zone of inhibition (14 mm) was recorded on Escherichia coli bacteria for the uncalcined PVA-ZnO/Mn2O3 nanocomposite compared to PVA, yet, less zone of inhibition compared to the calcined PVA-ZnO/Mn2O3 nanocomposite. The authors recommend the formation of the couple between metal oxides by electrochemical technique analyses as a future work.

Multifunctional application of PVA-aided Zn-Fe-Mn coupled oxide nanocomposite

Zinc oxide (ZnO) is a fascinating semiconductor material with many applications such as adsorption, photocatalysis, sensor, and antibacterial activities. By using a poly (vinyl alcohol) (PVA) polymer as a capping agent and metal oxides (iron and manganese) as a couple, the porous PVA-aided Zn/Fe/Mn ternary oxide nanocomposite material (PTMO-NCM) was synthesized. The thermal, optical, crystallinity, chemical bonding, porosity, morphological, charge transfer properties of the synthesized materials were confirmed by DTG/DSC, UV-Vis-DRS, XRD, FT-IR, BET, SEM-EDAX/TEM-HRTEM-SAED, and CV/EIS/amperometric analytical techniques, respectively. The PTMO-NCM showed an enhanced surface area and charge transfer capability, compared to ZnO. Using the XRD pattern and TEM image analysis, the crystalline size of the materials was confirmed to be in the nanometer range. The porosity and superior charge transfer capabilities of the PTMO-NCM were confirmed from the BET, HRTEM (IFFT)/SAED, and CV/EIS analysis. The adsorption kinetics (adsorption reaction/adsorption diffusion) and adsorption isotherm test confirmed the presence of a chemisorption type of adsorbate/methylene blue dye-adsorbent/PTMO-NCM interaction. The photocatalytic performance was tested on the Congo red and Acid Orange-8 dyes. The superior ascorbic acid sensing capability of the material was understood from CV and amperometric analysis. The noble antibacterial activities of the material were also confirmed on both gram-negative and gram-positive bacteria.

Use of Nanocellulose extracted from grass for adsorption abatement of Ciprofloxacin and Diclofenac removal with phyto, and fish toxicity studies

The present study deals with the adsorption of antibiotic Ciprofloxacin (CPXO) and anti-inflammatory agent Diclofenac (DCF) on Grass nanocellulose (GNC) extracted from Cyprus rotundas grass. The adsorbent GNC was characterised using various microscopic, elemental and spectroscopic analysis to monitor the physicochemical alterations of the surface before and after adsorption. The size of the converted nanocellulose was found to be 40-50 nm. The experimental measures influencing the adsorption of CPXO and DCF that were optimised are initial solution pH, GNC dosage, temperature and initial concentration of the adsorbate. Halsey isotherm model and pseudo-second order kinetic model agreed best with the experimental outcome for both the adsorbate. The maximum adsorption capacity of GNC were 227.223 and 192.307 mg/g for CPXO and DCF respectively. Phytotoxicity studies were performed using 6 different types of seeds to evaluate the effect of GNC treated effluent on plants. Similarly, acute fish toxicity on zebra fish analysis showed to have lesser mortality rate of the effluent after adsorption of CPXO and DCF on GNC.