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This review describes the occurrence and distribution of microplastics in freshwater and marine environments in recent years (2017-2022). Use of microplastics often results in contamination of aquatic environments, threatens biodiversity, and creates the need for environmental remediation. Such remediation strategies can involve primary, secondary, and tertiary treatments. Tertiary treatment is a frequent research subject due to its high efficiency and the possibility for advancements and enhancements. This study discusses tertiary treatments with remediation efficiencies of 95% and greater and their advantages, disadvantages, and future perspectives. Biochar-mediated remediation of microplastics is an effective method that may be able to achieve efficiencies approaching 100%. The study concludes by exploring methods of removing microplastics, including constructed wetlands and biochar, which offer high efficiency. PRACTITIONER POINTS: Tertiary treatments are an effective microplastic remediation strategy applicable succeeding secondary or primary treatments or as an individual remediation strategy. Biochar is a highly efficient adsorbent for microplastic remediation from aquatic environment with eco-friendly aspect and reusability. Modifications in tertiary treatments and enhancement in remediation efficiency are still a subject of research for future studies.

Lignocellulose wastes stemming from agricultural residues can offer an excellent opportunity as alternative energy solutions in addition to fossil fuels. Besides, the unrestrained burning of agricultural residues can lead to the destruction of the soil microflora and associated soil sterilization. However, the difficulties associated with the biodegradation of lignocellulose biomasses remain as a formidable challenge for their sustainable management. In this respect, metagenomics can be used as an effective option to resolve such dilemma because of its potential as the next generation sequencing technology and bioinformatics tools to harness novel microbial consortia from diverse environments (e.g., soil, alpine forests, and hypersaline/acidic/hot sulfur springs). In light of the challenges associated with the bulk-scale biodegradation of lignocellulose-rich agricultural residues, this review is organized to help delineate the fundamental aspects of metagenomics towards the assessment of the microbial consortia and novel molecules (such as biocatalysts) which are otherwise unidentifiable by conventional laboratory culturing techniques. The discussion is extended further to highlight the recent advancements (e.g., from 2011 to 2022) in metagenomic approaches for the isolation and purification of lignocellulolytic microbes from different ecosystems along with the technical challenges and prospects associated with their wide implementation and scale-up. This review should thus be one of the first comprehensive reports on the metagenomics-based analysis of different environmental samples for the isolation and purification of lignocellulose degrading enzymes.

In this research, a computational study is carried out to describe the insertion of a vital monomer, methyl 2-acetamidoacrylate (MAAA), into catalyst A (A = [(POOMe,OMe)PdMe]) (POOMe,OMe = 2[2-MeOC6H4](2-SO3-5-MeC6H4)P). Accordingly, the existence of both insertion products is found as a result of 1,2 and 2,1-insertion of MAAA in the Pd–Me bond. The 1,2-insertion of MAAA was more favorable due to the higher interaction energy among the monomers and catalyst A. Stable amide chelation was intended to hinder copolymerization and reduce the activity of catalyst A. As such, the 2,1-insertion product as a five-membered chelate could allow further insertion with a kinetically acceptable energy barrier compared to the six-membered 1,2-insertion product. The feasibility of a modified catalyst (C) (prepared from catalyst A) was also investigated to offset the effect of chelation on the copolymerization process. The newly modified catalyst (C) reduced the chelation effect by changing the steric factor around the metal (Pd) center. To upgrade the copolymer yield, the poor regioselectivity of monomer MAAA has been altered from the 1,2-insertion mode to the 2,1-insertion mode. Finally, the substituent (R) effect on C's aryl group revealed that certain substituents such as H and OMe were useful to increase the catalytic activity through the alteration of the electronic parameters.

Bioaerosols in the form of microscopic airborne particles pose pervasive risks to humans and livestock. As either fully active components (e.g., viruses, bacteria, and fungi) or as whole or part of inactive fragments, they are among the least investigated pollutants in nature. Their identification and quantification are essential to addressing related dangers and to establishing proper exposure thresholds. However, difficulties in the development (and selection) of detection techniques and an associated lack of standardized procedures make the sensing of bioaerosols challenging. Through a comprehensive literature search, this review examines the mechanisms of conventional and advanced bioaerosol detection methods. It also provides a roadmap for future research and development in the selection of suitable methodologies for bioaerosol detection. The development of sample collection and sensing technology make it possible for continuous and automated operation. However, intensive efforts should be put to overcome the limitations of current technology as most of the currently available options tend to suffer from lengthy sample acquisition times and/or nonspecificity of probe material.

In this manuscript, we report the insitu growth of gold nanoparticles (GNPs) and silver nanoparticles (SNPs) over Ce/Tb-doped Y-benzene tricaroboxylate metal organic frameworks (MOF-76). The photocatalytic potential of these nanocomposites (NCs) was then assessed for the photocatalytic reduction of p-nitrophenol (p-NP) in aqueous medium. The NCs had large surface area to favorably showcase the efficient absorption of light energy. Correspondingly, it facilitated the electron transfer between the valance and conduction bands to promote the reductive removal of p-NP. Among the tested catalysts, GNPs@MOF-76 (Ce) (MOF-76(1a)) (dosage: 10 μl of 5 mg.ml−1) recorded the maximum catalytic efficiency (96.3%) with an apparent rate constant ( K a p p ' : 0.33 min−1). Further, MOF-76 (1a) NCs exhibited good recyclability (e.g., a catalytic efficiency of 77.45% over 3 cycles). Moreover, the proposed NCs exhibited superior performance over commercial photocatalysts (e.g., p25 TiO2 nanopowder) towards p-NP reduction. As such, the results of this experimental study successfully demonstrated the superiority of the MOF immobilized nanoparticles (NPs) as an efficient platform for the removal of industrial grade pollutants.

In this study, the composition of mainstream smoke was investigated with an emphasis on a list of volatile organic compounds (VOCs: e.g., isoprene, acrylonitrile, methyl ethyl ketone, benzene, toluene, m-xylene and styrene) using the two types of flavor capsule cigarettes (FCCs, here coded as F1 and F2) in reference to one commercial, non-flavored (NF) and 3R4F cigarette. The concentrations of all the target compounds from FCCs were quantified under two contrasting conditions (i.e., with and without breaking the capsules). The effect of breaking the capsule was apparent in the FCC products with the enhancement of VOC levels, specifically between after and before breaking the capsules (e.g., 1.10-1.58 folds (benzene) and 1.30-1.53 folds (acetonitrile)). Such increases were apparent in both FCC samples if assessed in terms of the total amount of VOCs (TVOC): (1) F1 (from 2159 to 2530 μg cig

A facile/clean/sustainable route for the preparation of silver nanoparticles (Ag NPs) was investigated using Trigonella foenum-graecum (TF) leaf extract. The bio-reduced Ag NPs showed photocatalytic degradation potential of 88% and 86% for reactive blue 19 (RB19) and reactive yellow 186 (RY186), respectively (at 180 min). The complete mineralization of degraded medium was monitored by decline in chemical oxygen demand (COD). The role of activation energy in photocatalytic degradation process was investigated across different temperatures. In light of their photocatalytic efficiency, reusability, and environment friendly synthesis approach, biogenic Ag NPs were demonstrated as effective system for efficient water purification.

In this work, nickel oxide nanoparticles (NiO NPs) have been synthesised via cost-effective and highly convenient co-precipitation method, using cetyl trimethyl ammonium bromide (CTAB) as capping agent and NaOH as a reducing agent. The as-synthesised NPs have been analysed by a number of spectroscopic and microscopic techniques such as UV–visible spectroscopy, transmission electron microscope, X-ray diffraction, Fourier transformed infrared and energy dispersive X-ray. The prepared NiO NPs hold the prodigious potential towards the photocatalytic degradation of reactive blue 81 and Coomassie brilliant blue R-250 dyes with degradation efficiency of 90.8 and 95.7% and have high dye degradation rate constants of 1.3 × 10 − 2 min − 1 and 2.2 × 10 − 2 min − 1, respectively. Thus, this work signifies an efficient way to employ the NiO NPs as effective photocatalyst towards the alleviation of noxious industrial dyes.

Porous coordination compounds, commonly known as metal–organic frameworks (MOFs), exhibit many unique characteristics (e.g., high surface area, high porosity, and tunability). The corresponding naturally occurring counterparts, CD-MOFs have opened a new avenue of research in light of its non-toxic, edible, and renewable nature. These characteristics have led to their applications into numerous directions including drug delivery, CO2 capture, separation/purification, adsorption, sensors, food packaging, electrical conductors, memristors, photocatalysis, and polymerization. In this review, we provide a brief discussion about the available technologies for the synthesis of CD-MOFs and their applications in many prospective areas.

The pollution associated with hydrocarbons is one of the biggest threats to the environment, especially marine resources and wildlife. To date, numerous solutions have been proposed and implemented...

Rapid industrial growth has been accompanied by the pollution of hazardous volatile organic pollutants (VOCs) in air. Among various options available for the treatment of VOCs, the use of metal oxide composites as photocatalysts has been adopted preferably due to their potential to induce the synergistic interactions between the metal nanoparticles (NPs) and metal oxides (especially titanium dioxide (TiO

Surface plasmon resonance approach is a highly useful option to offer optical and label-free detection of target bioanalytes with numerous advantages (e.g., low-cost fabrication, appreciable sensitivity, label-free detection, and outstanding accuracy). As such, it allows early diagnosis of cancer biomarkers to monitor tumor progression and to prevent the recurrence of oncogenic tumors. This work highlights the recent progress in SPR biosensing technology for the diagnosis of various cancer types (e.g., lung, breast, prostate, and ovarian). Further, the performance of various SPR biosensors is also evaluated in terms of the basic quality assurance criteria (e.g., limit of detection (LOD), selectivity, sensor response time, and reusability). Finally, the limitations and future challenges associated with SPR biosensors are also discussed with respect to cancer biomarker detection.

Hypothesis Oil spills stemming from supertankers, drilling, and natural events represent a serious problem worldwide due to the potential harms to marine ecosystems and aquatic life. To date, various functional absorbents have been developed to treat spilled oil. Among them, carbon nanotube (CNT)-based aerogels and sponges gained attention due to superior performance in uptake and recovery of various types of oil and organic solvents. CNT aerogel/sponge absorbents are demonstrated for a multitude of merits such as: rapid superhydrophobic/superoleophilic absorption (water contact angle > 150°), high capacity (≥100 mg g−1), large surface area (300–400 m2 g−1)), enhanced strength and flexibility (>95% volume reduction and restoration of pristine morphology at 99% porosity), recyclability, and easy surface modification. Experiments This review compares CNT sponge–based absorbents with conventional techniques for remediation/recovery of spilled oil. Typically, synthesis of CNT sponges is performed using chemical vapor deposition (CVD) approach in the presence of a catalyst or using sacrificial removal of template. This work summarizes recent progress in strategies for oil-spill treatment based on CNT sponge techniques. The performance of CNT sponges for oil spill removal was evaluated in terms of their adsorption capacity, compressive stressability, and desorption methods (e.g., heat treatment, burning, or squeezing). Findings CNT sponges were observed to have high performance for removal of oil spills in terms of key performance metrics. This review offers valuable insights into the current state of CNT-mediated oil-spill cleanup technologies and guidance for future research at the same time. This literature survey would help the stakeholders (researchers, scientists, entrepreneurs, and commercial houses) pursue contamination-free water.

Porous materials have been identified as efficient sorbent media to remove volatile organic compounds. To evaluate their potential as adsorbents, the adsorptive removal of formaldehyde (FA) in aqueous environments was investigated using four materials, two water-stable metal–organic frameworks (MOFs) of UiO-66 (U6) and U6-NH2 (U6N) and two covalent organic polymers (COPs) with amine-functionality, CBAP-1-EDA (CE) and CBAP-1-DETA (CD). U6N exhibited the highest removal capacity of 93% (0.56 mg g–1) of the tested materials [e.g., CE (81.1%, 0.53 mg g–1) > CD (67.2%, 0.43 mg g–1) > U6 (66.9%, 0.42 mg g–1)], which was 2 times higher than that of the reference sorbent, activated carbon (AC: 50%, 0.30 mg g–1). The results of Fourier transform infrared and powder X-ray diffraction analyses confirmed the interactions between FA molecules and the amine components of the materials (U6N, CD, and CE). According to density functional theory calculations, the formation of hydrogen bonds between FA molecules and amine c...

Nanomaterials have been the subject of intense and extensive research in developing various optical sensing tools due to their light dependent remarkable structural and functional attributes. In this review, we conducted a comprehensive and critical assessment of the optical sensing methods (e.g., colorimetry and fluorometry) using various types of nanomaterials (e.g., metal organic frameworks, metal nanoparticles, carbon nanomaterials, quantum dots, chiral molecules, and polymers). Special emphasis was placed on explaining key factors that govern their sensing capabilities, sensing mechanisms, and practical applications toward optical sensing of diverse metal species. Some recent case studies elaborating on the detection of toxic and heavy metal species are described in depth. The discussion is also extended to assess the reliability of nanomaterial-based optical sensing approaches with respect to their performance along with the major challenges and constraints in this research field.

Development of benign and efficient approaches towards abatement of industrial grade toxic organic dyes from the fresh water resources is an evolving challenge. To this end, current study was focused on the removal of reactive yellow 186 dye (RY-186) dye using green synthesized SnO2 nanoparticles prepared from Piper betle leaf extract. As synthesized nanoparticles were characterized by pertinent spectroscopy and microscopy tools, which ascertained the formation of highly crystalline, spherical, and ultrafine nanoparticles of 8.4 nm diameter with tetragonal rutile structure. Nanoparticle catalyzed photolysis of RY-186 dye in presence of sunlight revealed degradation efficiency and apparent rate constant (K’app) values as 92.17% and 1.3 × 10−2 min−1, respectively. Kinetic analysis of the dye degradation process rendered manifestation of pseudo-first order kinetics. Current study demonstrated the application of biogenic SnO2 NPs as a heterogeneous catalyst towards the purification of industrially polluted water for the savage of the environment.

The manuscript reports synthesis of exceptionally stable gold nanoparticles (GNPs) using Momordica charantia fruit extract. The synthesis approach was optimized by refining three experimental variables including source of the fruit extract (peel, seed, and seed coat), pH of the solution, and temperature of the reaction medium. As synthesized GNPs showed excellent stability against various thiolated compounds (e.g., thioglycolic acid, thiourea, l -cystine, 1-dodecanethiol, and cysteamine hydrochloride). Moreover, these nanoparticles showed distinctive colorimetric responses against Cd2+ and thiophenol (TP) from their potential interferences. The limit of detection (LOD) values for Cd2+ and TP were determined as 0.186 and 0.154 μM, respectively.

Luminescent metal organic frameworks (LMOFs), formed by coordinated bridging between metal ions and multidentate organic ligands with relevant fluorescent structures, have been the subject of intense research due to their tunable photoluminescent properties. The numerous permutations and combinations of available metal ions and organic linkers can yield novel LMOFs for countless applications. The luminescent characteristics of LMOFs depend upon many factors, including their structural components, coordination milieu of the metal ions, chemical structure/volume of the pore surfaces, and host-guest interactions between the LMOFs and reacting species (e.g., non-covalent interactions, coordination bonds, and π-π interactions). The combined effects of these parameters justify the expansion of their application in various fields. In addition, they are recognized as ideal candidates for biological applications due to their high loading capacity of functional molecules, facile surface modification and conjugation with biocompatible ligands (such as antibodies and proteins), tunable structural geometry, and intrinsic biocompatibility. By elaborating on these points, this article provides up-to-date information on the developments in the scientific/technological application of LMOFs, with special emphasis on the types, properties, and potential in sensing and biological applications. The discussion is further expanded to describe the major challenges and constraints of this research field.

In this study, we investigated the optimal conditions for solvothermal-assisted synthesis of Eu-BDC-NH2 metal organic frameworks (MOFs) to improve their sensing capacity toward some selected target metal species. To this end, we focused on the interactive relationships between key synthesis variables (e.g., the relative molar ratios (and absolute amounts) of the reactants [EuCl3·6H2O vs. amino terephthalic acid (BDC-NH2)], temperature, and reaction duration). It was observed that different types of MOFs synthesized under diverse conditions consistently exhibited emission profiles of Eu3+. However, their luminescence properties were distinguished systematically by the synthesis conditions set for each sample group. The sensing potential of luminescent MOFs was explored for detection of toxic metal ions through two approaches, i.e., direct chemosensing and indirect biomolecule mediated sensing approach. In the former, the MOFs exhibited noticeable turn-off fluorescence behavior, especially with Hg2+ ions (i.e., a high Stern-Volmer quenching constant (Ksv) of 6.42 × 105 M−1 and limit of detection (LOD) of 0.007 M). In the latter, nanocomposites of MOFs-cyanocobalamin were characterized by a highly selective turn on fluorescence response towards Co2+ ions (Ksv = −6.25 × 103 M−1; LOD = 0.7 M). As such, the sensing capacity of these MOFs was distinguished efficiently by control of synthesis variables.

Despite the improvement in sensing technologies, detection of small and highly reactive molecules like formaldehyde remains a highly challenging area of research. Applications of nanomaterials/nanostructures and their composites have increased as effective sensing platforms (e.g., reaction time, sensitivity, and selectivity) for the detection of aqueous or gaseous formaldehyde based on diverse sensing principles. In this review, the basic aspects of important nanomaterial-based sensing systems (e.g., electrochemical, electrical, biological, and mass variation sensors) were evaluated in relation to performance, cost, and practicality of sensing gas phase formaldehyde. Accordingly, existing knowledge gaps in such applications were assessed in various respects along with suitable recommendations for building a new roadmap for the expansion of chemical sensing technology of gas phase formaldehyde.

The use of fragrances is often essential to create an elegant, welcoming, or exhilarating environment. Through encapsulation, the release and delivery of fragrances are customized in many consumer products. For such purposes, cost-effective techniques have been developed and employed with the use of various polymers and porous organic materials to efficiently impart fragrances to foods and various other consumer products. After entrapment or uptake/storage of fragrant molecules within a polymeric complex, the properties can be investigated by automated thermal desorption (ATD) analysis. For efficient delivery, fragrances are adsorbed (or entrapped) in some media (e.g., fabric or paper). The release of such entrapped fragrances usually is achieved by spraying. Fragrances can be also loaded in a media by purging aroma gases or by adding fragrance essence directly into a liquid medium. Porous materials, such as zeolites, have been traditionally used for air purification as well as in cosmetics and similar applications. Similarly, other polymeric porous complexes have also been used in fragrance delivery as a templating agent for aromatherapy textiles. Such polymeric materials offer an advantage in terms of development of new hybrid blends via homogenous mixing of two or more matrices. Such blends may possess different desirable physical properties as encapsulants. This review article is aimed at presenting an overview of polymers and their complexes as the main media of fragrance encapsulation. This study also discusses the expansion and future application of porous materials as host matrices for fragrances.

The manuscript reports wet chemical assisted low temperature synthesis of CTAB stabilized elongated triangular bipyramidal shape nanostructures of ZnO for photocatalytic degradation of methyle blue (MB) and congo red (CR) dyes. Physiochemical characterization has been carried out by X-ray diffraction, scanning electron microscope, transmission electron microscope and UV-visible spectroscope. Pure wurtzite structure of ZnO with crystallite size ~56 nm has been confirmed from X-ray study. Well dispersed particles with elongated triangular bipyramidal morphology have been observed through SEM. Fine resolved particles with varied aspect ratios ~80 X 200 ± 10 nm have been depicted by TEM images. UV-visible absorption analysis confirms the energy band gap of 3.43 eV for synthesized ZnO particles. Molecular composition and functional groups of CTAB were confirmed by FTIR spectroscopy. The potential applicability of the particles for photocatalytic degradation of MB and CR as standard analytical dyes was studied. Time bound study under UV irradiated source depicted more than 95% degradation of both dyes in separate experiments.

This research work is an effort towards the purification of industrially polluted water for the savage of the environmental system. Optimized fructose modified ZnO nanoparticles were used as adsorbent as well as a photocatalyst for the removal of dyes from polluted water. Textile synthetic dyes were used as model pollutants. Structural and optical properties of the synthesized fructose modified ZnO nanoparticles were analyzed using XRD, SEM, TEM, and UV–Vis spectrophotometer. Wurtzite hexagonal phase with the quasi-spherical shape of diameter 14–40 nm of fructose modified ZnO nanoparticles were obtained by optimizing various reaction parameters. As compared to the bulk, fructose modified ZnO nanoparticles show a blue shift in the excitation absorption; confirming quantum confinement. The effect of pH, time, and initial dye concentration was investigated on the dye removal efficiency of the synthesized fructose modified ZnO nanoparticles. Through the kinetic study of dye removal, it has been observed that the adsorption and photodegradation phenomenon followed pseudo-first order kinetics.

An innovative and facile sensing approach for common inorganic anions present in aqueous media has been developed using nanocomposites of europium doped graphene quantum dots (GQDs:Eu) with zeolitic imidazole frameworks (ZIF-8). GQDs:Eu, prepared initially by solvothermal approach (at − , Cl − , F − , and NO 3 − ). Among the tested ions, GQDs:Eu-ZIF-8 were found to effectively and sensitively detect sulfide (S 2− ) with significantly high turn on fluorescence. The feasibility of this nanosensing system was explored further toward the detection of S 2− ions. These nanocomposites were thus demonstrated to be feasible for solution-based sensing of S 2− ions with high reproducibility and sensitivity at limit of detection (LOD) of 0.12 ppm.

Zeolitic imidazolate frameworks (ZIFs) can be classified as metal–organic frameworks (MOFs) or metal-azolate frameworks (MAFs) with unique topologies. The presence of five membered heterocyclic ring structure in imidazole ring-based linkers facilitates their robust coordination with bridging metal nodes. This stable coordination imparts numerous advantageous properties (e.g., facile and reproducible crystallization, nanoscale processability, high loading capacities, and good biocompatibility) to ZIFs. Further, the technical advancements in the synthesis of porous coordination polymers have contributed to the diversification in the fabrication approaches needed for the ZIFs and to the characterization of their structural and functional attributes (e.g., ZIF-8 and ZIF-67). In light of this advancement in ZIF technologies, we describe the synthesis methods for the fabrication of ZIFs in relation to their resulting properties. This review also highlights the application of ZIF-based probes for sensing of a diverse array of targets (e.g., gas molecules, metabolites, pesticides, and metals). Further, a performance comparison between various ZIF-based sensing systems has been made for the listed target analytes in terms of various quality assurance (QA) criteria (e.g., sensor response and recovery time, limit of detection (LOD), specificity, and reproducibility). At last, the current challenges and future outlook for this research field are also discussed to help expand their real-world applications.

This research describes the synthesis of a covalent bioconjugate of graphene quantum dots (GQDs) and glutaminase (10 units·mg−1) for electrochemical and photoluminescent (PL) detection of L-glutamine (Gln). As synthesized GQDs exhibited uniform size distribution, (average diameter ~5–10 nm, and discrete blue emission characteristics (λex = 391 ± 2 nm and λem = 480 ± 2 nm)). Accordingly, the immobilization of glutaminase over the surface of the GQDs was confirmed by the characteristic Fourier-transform infrared (FTIR) spectroscopy peaks of the amide bond at 1,703 and 1,390 cm−1. The conjugate was used to detect Gln using electrochemical and PL approaches on a parallel basis over a concentration range of 100–1,000 µM. Electrochemical analysis of Gln using cyclic voltammetry revealed a limit of detection (LOD) and limit of quantification (LOQ) values of 360.4 µM and 1,100 µM, respectively. In comparison, quantification of Gln based on the PL approach yielded a Stern-Volmer quenching constant, LOD, and LOQ values of 2.2 × 103 M−1, 9.42 µM, and 28.57 µM, respectively. As such, the PL spectroscopy-based analysis was seen to have better sensitivity for Gln quantification than the electrochemical analysis. The PL-based approach is a more recommendable option for Gln quantification with high sensitivity and rapidity.

A nanoreactor (NR) was synthesized by encapsulating acetylcholinesterase (AChE) in zeolitic imidazolate framework (ZIF)-8 (AChE@ZIF-8 NR). The catalytic activity of the NR was tested for the hydrolysis of acetylthiocholine chloride (ATCh) based on the Ellman’s assay to yield a characteristic yellow color at a maximum wavelength (λmax) of 412 nm. The catalytic activity of AChE@ZIF-8 NR showcased noticeable enhancements in maximum reaction rate (νmax: 1.25 × 10−12 kat) and low Michaelis-Menton constant (Km: 0.05 mM (10 ppm)). The NR-based hydrolysis of ATCh was inhibited in the presence of each of all seven types of organophosphate pesticides (malathion (MAL), methyl parathion (MP), glyphosate (GLY), glufosinate (GLU), chlorpyrifos (CPF), dichlorvos (DCV), and paraoxon (PAR)) selected in this study. The limit of detection (LOD) values for GLY, GLU, and MAL were estimated almost identically as 10−5 ppb. However, their limit of quantification (LOQ) was slightly distinguished as 0.05, 0.01, and 0.05 ppb, respectively. The NR retained 46% of its activity over the course of 5 cycles of sequential activation and MAL-induced inhibition. In comparison to the other reported studies, our approach provides a rapid means for sensing of OPs with appreciable stability, enhanced recyclability, and facile observation.

The manuscript reports an efficient approach for the synthesis of biogenic silver (Ag) nanoparticles from Azadirachta indica leaf extract-mediated reduction of silver nitrate under solar ra...

The manuscript reports plasticizer-mediated conversion of poly(e-caprolactone) hollow particles into microcapsules followed by encapsulation and sustained release of doxorubicin from the microcapsules through a progressive approach. Plasticizer molecules account for increased mobility of polymer chains. Chloroform was observed to be the best plasticizer for potential transformation of the hollow particles into microcapsules, compared to 1,4-dioxane, and toluene. In the next step, an anticancer drug doxorubicin was encapsulated in the hollow particles in presence of chloroform. In vitro release of drug from the microcapsules in phosphate buffer saline (pH 7.4) demonstrated sustained release pattern over 15 days.

In the present research work, crystallographic, optical, molecular, morphological and magnetic properties of Zn1-xCuxO (ZnCu) and Zn1-x-yCeyCuxO (ZnCeCu) nanoparticles have been investigated. Polyvinyl alcohol (PVA) coated ZnCu and ZnCeCu nanoparticles have been synthesized by chemical sol-gel method and thoroughly studied using various characterization techniques. X-ray diffraction pattern indicates the wurtzite structure of the synthesized ZnCu and ZnCeCu particles. Transmission electron microscopy analysis shows that the synthesized ZnCu and ZnCeCu particles are of spherical shape, having average sizes of 27 nm and 23 nm, respectively. The incorporation of Cu and Ce in the ZnO lattice has been confirmed through Fourier transform infrared spectroscopy. Room temperature photoluminescence spectra of the ZnO doped with Cu and co-doped Ce display two emission bands, predominant ultra-violet near-band edge emission at 409.9 nm (3 eV) and a weak green-yellow emission at 432.65 nm (2.27 eV). Room temperature magnetic study confirms the diamagnetic behavior of ZnCu and ferromagnetic behavior of ZnCeCu.

The manuscript reports facile one step synthesis of CuO semiconductor nanorods by sol-gel aaproach for photocatalytic and bioremediation applications. Spectroscopic characterization along with X-ray diffractometry and electron microscopy studies confirmed the formation of nanorods with 12 to 14 nm diameter and 50-100 nm length. As synthesized nanorods were subjected to photocatalytic degradation of dyes viz. Methylene Orange (MO), Methylene Blue (MB), Eriochrome Black T (ET) and Congo Red (CR) in a time bound study. Comparative analysis of the data depicted that time taken for degradation of equal amount of CR was more compared to the other three dyes owing to its high molecular weight and lower diffusion rate in aqueous medium. Subsequently, the antibacterial properties of the nanorods were investigated against the gram negative Escherichia coli and gram positive Bacillus bacteria. Zone of clearance was observed in disk diffusion assays, thereby confirming the antibacterial characteristics of the nanorods. These nanorods thus hold great promise as a simple, selective and a sensitive analytical platform for the effective bio-monitoring and photocatalyst for dye degradation.

Metal–organic frameworks (MOFs) have potential as air quality treatment media for various gaseous pollutants (e.g., ammonia) through diverse mechanisms (capture and catalytic degradation). A broad range of MOFs have been developed with numerous advantageous properties (e.g., high surface area, high degree of porosity, intrinsically tunable chemical structure, flexible architecture, and multifunctional properties) to meet strict air quality metrics. Nevertheless, the practical use of these novel materials has also been restricted due to certain drawbacks including high fabrication costs, poor selectivity, low capacity, and difficulties in recycling/regeneration. This review was organized to highlight the recent advancements in MOF technology for the mitigation of ammonia. The article aims to expand the use of MOFs in air quality treatments by identifying the research gaps in associated fields.

The low permissible concentration of lead ions (Pb2+) in potable water (15 ppb) makes it even more challenging to develop highly efficient water purification technologies. Adsorption has become one of the preferred water treatment techniques for removing various metal species including Pb2+ ions. However, assessment of adsorbent capacities between the tested materials was often made in a biased manner (e.g., derivation of the maximum capacities under unrealistically high initial feeding conditions). In this work, such comparison was made in terms of partition coefficient (PC) as a key metric for the least biased evaluation to explore the best sorbents among materials with a broad range of breakthrough capacities. Nanoscale sorbents derived from carbon-based nanomaterials and MOFs are highly advantageous, as they can offer highly sensitive and selective adsorption of Pb2+ ions. In general, advanced functional materials showcased better adsorption-desorption efficiency for Pb2+ when compared to conventional materials (e.g., over three regeneration cycles). Continuous research and development for the functional materials are further required to scale down the production cost so that cost-effective technologies may be applied for environmental remediation. The future scope for Pb2+ removal techniques is discussed further with respect to the development of novel functional materials.

The quest for advanced management tools or options of various cancers has been on the rise to efficiently reduce their risks of mortality without the demerits of conventional treatments (e.g., undesirable side effects of the medications on non-target tissues, non-targeted distribution, slow clearance of the administered drugs, and the development of drug resistance over the duration of therapy). In this context, nanomaterials-antibody conjugates can offer numerous advantages in the development of cancer theranostics over conventional delivery systems (e.g., highly specific and enhanced biodistribution of the drug in targeted tissues, prolonged systemic circulation, low toxicity, and minimally invasive molecular imaging). This review comprehensively discusses and evaluates recent advances in the application of nanomaterial–antibody bioconjugates for cancer theranostics for the further advancement in the control of diverse cancerous diseases. Further, discussion is expanded to cover the various challenges and limitations associated with the design and development of nanomaterial-antibody conjugates applicable towards better management of cancer.

There is a dire need for development of efficient and sensitive methods to efficiently screen parabens. In this research, we focused on quantification of four parabens (i.e., methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butyl paraben (BP)) using chitosan intercalated nickel/iron layered double hydroxide (CS–Ni/Fe-LDH) composites as solid phase extraction sorbent prior to HPLC-PDA analysis. CS-Ni/Fe LDH composites with a heterogeneous, porous texture, and coral reef-like structure exhibit appealing extraction efficiency for the target parabens due to the enhanced possibility for the formation of hydrogen bonding and hydrophobic interactions. The performance of the composites was assessed and optimized for solid phase extraction of parabens from standard samples and real samples (rose water, cream, toothpaste, hair serum, and sunscreen). The LDH-SPE-HPLC method exhibited a wide linear range (e.g., 100–50,000 ng L−1), good linearity (R2 ≥ 0.999), and good precision (relative standard deviation (RSD)

Tunable properties of porous metal organic frameworks (MOFs) make them a potential candidate for sustained release of functionally active biomolecules. Current study describes in situ encapsulation of anti-cancer drug, docetaxel in iron based MOFs for drug delivery applications. MOFs were synthesized using emulsification approach by mixing FeCl3.4H2Oand benzene tricarboxylate (BTC) in 1:1 molar ratio in the presence of cetyl trimethyl ammonium bromide (CTAB). Optical characterization of the NMOFs was done using UV-visible and FTIR spectroscopy. The peak obtained at 265 nm in the UV-visible spectrum indicated the formation of iron-based NMOF. The peaks obtained at 3416, 1623 and 3343cm-1 corresponding to C=O, C=C and C=O groups in FTIR spectroscopy further supported our observations. Microencapsulation of docetaxel was achieved by mixing the drug with the iron salt during the synthesis of MOF. Drug encapsulation was affirmed by Transmission Electron Microscopy. Current study is an attempt in exploring the microencapsulation properties of MOFs.

Highly porous crystalline luminescent metal Organic Frameworks (MOFs) were synthesized by conjugating Yttrium nitrate and Benzene Tri Carboxylate (BTC) in the presence of surfactant Cetyl Tri methyl Ammonium Bromide. A characteristic blue emission peak around 400 nm of Y upon excitation with UV light and peaks through Infra-Red spectroscopy revealed the formation of co-ordinate bond between Y and BTC, thereby confirming the formation of MOF nanoparticles (NPs). The nanoparticles were studied for potential removal of pollutants by encapsulation of the dye methylene blue (MB). Optical analysis affirmed the encapsulation of dye particles within the porous MOF NPs as dye absorption decreased around 600nm. This study offers great promise of using MOF NPs as platform for sensing of analytes in solution and removal of pollutant materials.

Progress in the design, synthesis, and modification of metal-organic frameworks (MOFs) has immensely helped expand their applications in a wide variety of research fields. Such developments offered great opportunities for upgrading their efficiencies in diverse photocatalytic applications (e.g., N2/CO2 reduction, H2 generation, organic synthesis, and environmental remediation) through enhanced conversion/storage of solar energy. The MOF-based photocatalytic platforms are, nonetheless, subject to many practical problems (e.g., inapplicability for industrial upscaling and thermodynamic instability under environmental conditions). In this review, the effects of synthesis/modification strategies on MOF photocatalysis have been discussed with respect to the type of inorganic nodes, the modulation of organic ligands, and the pre-/post-synthesis modification in MOF networks (i.e., MOF-based composite). Particular emphasis was placed on the technical advances achieved in the photoelectronic/catalytic performances of MOFs in multiple energy/environmental (redox) reactions based on both experimental and theoritical analyses. Further, the technical merits/disadvantages of MOF photocatalysts (in terms of structural defects, light absorption, active sites, and kinetic/thermodynamic stability) have been evaluated in relation to quantum efficiency and charge transfer mechanisms in various photo-redox reactions. The pursuit of strategies for enhanced kinetic stability of MOFs have also been highlighted based on the nature/strength of coordination modes, the inertness of metal centers, and the functionality of ligand types. Lastly, the current limitations of MOF-based photocatalysts are addressed with respect to their practical applications at industrial scales along with a discussion on their future use.

The progress in modern agricultural practices could not have been realized without the large-scale contribution of assorted pesticides (e.g., organophosphates and nonorganophosphates). Precise tracking of these chemicals has become very important for safeguarding the environment and food resources owing to their very high toxicity. Hence, the development of sensitive and convenient sensors for the on-site detection of pesticides is imperative to overcome practical limitations encountered in conventional methodologies, which require skilled manpower at the expense of high cost and low portability. In this regard, the role of novel, advanced functional materials such as metal-organic frameworks (MOFs) has drawn great interest as an alternative for conventional sensory systems because of their numerous advantages over other nanomaterials. This review was organized to address the recent advances in applications of MOFs for sensing various pesticides because of their tailorable optical and electrical characteristics. It also provides in-depth comparison of the performance of MOFs with other nanomaterial sensing platforms. Further, we discuss the present challenges (e.g., potential bias due to instability under certain conditions, variations in the diffusion rate of the pesticide, chemical interferences, and the precise measurement of luminesce quenching) in developing robust and sensitive sensors by using tailored porosity, functionalities, and better framework stability.