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2D ZnO nanostructure-based biosensors: synthesis, classification, types and applications.

Slow kinetics and emotive design of electrocatalysts are the main barriers to effective oxygen evolution and hydrogen production from water. To overcome these challenges, nickel sulfide impregnated electrocatalysts with auxiliary structural features have recently attracted attention as effective alternatives for the oxygen evolution reaction (OER). Herein, nickel sulfide (NiS) nanowires are developed directly on nickel foam (NF), which have proven to be a highly efficient electrocatalyst for OER in an alkaline medium. For this, NiS nanowires were grown on NF for short intervals of 30, 60, 90 and 120 min through an aerosol-assisted chemical vapor deposition (AACVD) process using nickel diethyldithiocarbamate as a precursor. The as-developed NiS electrode showed excellent OER activity in 1.0 M KOH solution. It is noteworthy that the NiS electrode produced after 90 min provides a reference current density of 10 mA cm−2 at an overpotential (η) of 210 mV and achieves a higher current density of 500 mA cm−2 at an overpotential of 340 mV. Moreover, the nanocatalyst has observed a low Tafel value (60 mV dec−1) and good OER stability. After the electrolysis, it was found that the surface of the NiS catalyst was partially modified into nickel oxide. The S atom in the NiS catalyst can provide an activator function that first converts the sulfide to a hydroxide and then eventually becomes an oxyhydroxide species. The more active nickel hydroxide/oxyhydroxide phase raises the water oxidation performance to a new level. The facile synthesis of NiS nanowire films by AACVD tends to be used as an anodic material in various other power generation and energy conversion devices such as batteries, fuel cells, and supercapacitors.

In the scope of the rapid technological advancements, nanoparticles (NPs) have gained prominence due to their excellent and tunable biological, and physicochemical properties. Nowadays, different methods are used for their synthesis. In particular, the green synthesis of metal precursors for the synthesis of NPs, represents a cost-effective, environmentally friendly, and hazardous chemical-free method for developing a large variety of NPs. By exploiting plant extracts, the production rate of NPs is relatively faster. Due to fossil reserves and high fuel consumption, renewable and clean energy materials are urgently needed to improve environmental sustainability. With outstanding electrochemical and physicochemical characteristics, molybdenum-based NPs (Mo-NPs) are gaining increasing attention in the fields of energy conversion and storage. Considering the significance of Mo-NPs synthesized from greener routes and their energy applications, it is necessary to review recent trends and developments in this field. This review summarizes important research studies and future research guidelines for the preparation of Mo-NPs through green routes and their applications to meet global energy and environmental demands. Moreover, future research directions are also highlighted to achieve sustainable greener precursors and Mo-NPs based energy storage devices.

Abstract: Rice (Oryza sativa L.), a cereal grass, belongs to the genus Oryza from the family Poaceae, which encompasses twenty-five species cultured in many countries of Asia, and partly in the rest of the world. From these species, two viz. Oryza sativa (O. sativa) Asian rice and Oryza glaberrima (O. glaberrima) African rice are commonly found and the most widely consumed staple food by a large part of the human population in the world, especially in Asia due to their nutritional and nutraceutical prospects. Rice, a popular source of carbohydrates, also contains a good amount of dietary fiber, minerals (Ca, Zn, Se, P, K, Mg, Fe, and Mn), protein and vitamin B along with several other medicinally important bioactives such as tocols (α-tocopherols and α-tocotrienols) (ß-sitosterol) phenolic acids, flavonoids (apiginine), and oryzanol (24-Methylenecylcoartanyl trans-ferulate). Rice bran is a byproduct of the rice polishing industry and is valuable in terms of containing 15-20% high-value oil. Because of the natural antioxidants present in rice, several medicinal benefits and biological properties can be attributed to rice consumption. The nutrient profile of rice varies based on several factors, such as grains (white, brown, red, and black/purple), the extent of polishing, and the preparation method. Considering the importance of rice as a traditional diet rich in high-value bioactives, together with the existing gap of related information, it is worthwhile to assemble a comprehensive review that focuses on the detailed profile of valuable nutrients and high-value phytochemicals and biological activities of rice to explore its functional food and nutraceutical applications. This review attempts to provide collective information on the essential rice cereal for its nutritional and antioxidant potential.

Background: Lip and oral squamous cell carcinoma maintains a significant disease burden in Pakistan. The latest research on cancer focuses more on the role of body’s immune response in tumour progression and spread rather than on the nature of neoplastic cells. Tumour-infiltrating lymphocytes constitute a major part of tumour microenvironment and infiltration of tumour stroma by cytotoxic T-cells are known to limit the tumour progression in various malignancies, such as, colorectal and stomach cancers. In our study, we aim to establish the prognostic role of CD8+ tumour-infiltrating lymphocytes in lip and oral squamous cell carcinoma. Methods: Clinico-pathological data and paraffin-embedded blocks were obtained for 100 cases of lip and oral squamous cell carcinoma. These cases were selected through non-probability, convenience sampling at the Histopathology department of A.F.I.P., Rawalpindi. Fresh sections from the tumour proper were taken and CD8 immuno-marker was applied. Data was recorded, entered and analyzed with S.P.S.S. version 27.0 and Microsoft Excel. Qualitative variables were represented as frequency/percentages and quantitative variables were represented as mean and standard deviation. Chi-squared test was applied to test association between categorical data. A p-value of

Background: Carcinomas of the salivary gland are known to be aggressive in nature, making them difficult to manage. The therapeutic options offered include excision of the gland (maxillectomy in cases of palatal tumours), with or without lymph node dissection, proceeded with radiotherapy. Chemotherapy has not produced promising outcomes and has a minimal impact as a therapeutic alternative. Targeted therapy against human epidermal growth factor receptor 2 (HER-2), which is a commonly used treatment modality for their mammary analogues, is not being offered to these patients since scant literature is available showing its usefulness and no promising evidence is present regarding their efficacy and efficiency in such cases. The study aimed to evaluate and quantify the immunohistochemical expression of HER-2 in cases of adenoid cystic carcinoma (AdCC), mucoepidermoid carcinoma (MEC) and salivary duct carcinoma (SDC), which are analogues of similar tumours arising in breast tissue. Methods: A retrospective, cross-sectional study was carried out in the department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi, duration of which was six months. A total of 45 cases (15 of each tumour) were taken, and sampled using non-probability convenience technique. The immunohistochemical marker, monoclonal HER-2 antibody (Leica microsystem Germany) was applied on appropriate blocks of all included cases. The staining pattern and intensity were recorded after visualizing the slides under a light microscope. Results: Seven cases of salivary duct carcinoma and a single case of mucoepidermoid carcinoma expressed positivity for HER-2, while no expression could be seen in the case of adenoid cystic carcinoma. A statistically significant difference was seen when HER-2 expression was compared among the aforementioned tumours. Conclusion: The use of targeted therapy against HER-2 is limited to patients of salivary duct carcinoma and a fraction of patients suffering from mucoepidermoid carcinoma.

Effect of ORM on cell cycle analysis and β-catenin localization. A. Histogram (i) and table (ii) represent the cell cycle distribution in DU145 cells. B. Confocal images of β-catenin, DAPI and merged images of control (i) and ORM treated (ii) PC3 cells.

Ormeloxifene is a clinically approved selective estrogen receptor modulator, which has also shown excellent anticancer activity, thus it can be an ideal repurposing pharmacophore. Herein, we report therapeutic effects of ormeloxifene on prostate cancer and elucidate a novel molecular mechanism of its anticancer activity. Ormeloxifene treatment inhibited epithelial-to-mesenchymal transition (EMT) process as evident by repression of N-cadherin, Slug, Snail, vimentin, MMPs (MMP2 and MMP3), β-catenin/TCF-4 transcriptional activity, and induced the expression of pGSK3β. In molecular docking analysis, ormeloxifene showed proficient docking with β-catenin and GSK3β. In addition, ormeloxifene induced apoptosis, inhibited growth and metastatic potential of prostate cancer cells and arrested cell cycle in G0–G1 phase via modulation of cell-cycle regulatory proteins (inhibition of Mcl-1, cyclin D1, and CDK4 and induction of p21 and p27). In functional assays, ormeloxifene remarkably reduced tumorigenic, migratory, and invasive potential of prostate cancer cells. In addition, ormeloxifene treatment significantly (P < 0.01) regressed the prostate tumor growth in the xenograft mouse model while administered through intraperitoneal route (250 μg/mouse, three times a week). These molecular effects of ormeloxifene were also observed in excised tumor tissues as shown by immunohistochemistry analysis. Our results, for the first time, demonstrate repurposing potential of ormeloxifene as an anticancer drug for the treatment of advanced stage metastatic prostate cancer through a novel molecular mechanism involving β-catenin and EMT pathway. Mol Cancer Ther; 16(10); 2267–80. ©2017 AACR.

Supplementary Figure S4. Schematic representation of the treatment regime of xenograft mice.

The management of pancreatic ductal adenocarcinoma (PDAC) is extremely poor due to lack of an efficient therapy and development of chemoresistance to the current standard therapy, gemcitabine. Recent studies implicate the intimate reciprocal interactions between epithelia and underlying stroma due to paracrine Sonic hedgehog (SHH) signaling in producing desmoplasia and chemoresistance in PDAC. Herein, we report for the first time that a nonsteroidal drug, ormeloxifene, has potent anticancer properties and depletes tumor-associated stromal tissue by inhibiting the SHH signaling pathway in PDAC. We found that ormeloxifene inhibited cell proliferation and induced death in PDAC cells, which provoked us to investigate the combinatorial effects of ormeloxifene with gemcitabine at the molecular level. Ormeloxifene caused potent inhibition of the SHH signaling pathway via downregulation of SHH and its related important downstream targets such as Gli-1, SMO, PTCH1/2, NF-κB, p-AKT, and cyclin D1. Ormeloxifene potentiated the antitumorigenic effect of gemcitabine by 75% in PDAC xenograft mice. Furthermore, ormeloxifene depleted tumor-associated stroma in xenograft tumor tissues by inhibiting the SHH cellular signaling pathway and mouse/human collagen I expression. Xenograft tumors treated with ormeloxifene in combination with gemcitabine restored the tumor-suppressor miR-132 and inhibited stromal cell infiltration into the tumor tissues. In addition, invasiveness of tumor cells cocultivated with TGFβ-stimulated human pancreatic stromal cells was effectively inhibited by ormeloxifene treatment alone or in combination with gemcitabine. We propose that ormeloxifene has high therapeutic index and in a combination therapy with gemcitabine, it possesses great promise as a treatment of choice for PDAC/pancreatic cancer. Cancer Res; 75(11); 2292–304. ©2015 AACR.

Legends for Supplementary Figures S1-S4.

Objective: To assess the vulnerability of atherosclerotic plaque in coronary arteries of individuals dying of ischemic heart disease. Study Design: Cross sectional study. Place and Duration of Study: Histopathology department, Combined Military Hospital Lahore, from Nov 2016 to Nov 2017. Methodology: A total of 43 cases were taken in the study. The Autopsy specimens from the bodies of people dying suddenly of ischemic heart disease were taken into the study. Tissues showing autolytic changes and patients dying with coronary artery disease after corrective procedure like stenting and bypass were excluded. Results: Out of 43 cases, 35 (81.4%) cases were positive for cluster of differentiation 68 (CD 68), 34 (79%) cases were positive for cluster of differentiation 105 (CD 105) & 36 (83.6) cases were positive for nuclear factor kappa-light-chain-enhancer of activated B cells (NF-Kb). Conclusion: People who had died of ischemic heart disease have more vulnerable plaque in their coronary arteries as compared to the people who had died of non-ischemic cause. Early recognition of the un-ruptured plaque is important for the treatment strategies.

The current research aimed at designing mesoporous silica nanoparticles (MSNs) for a controlled coadministration of salicylic acid (SA) and ketoconazole (KCZ) to effectively treat highly resistant fungal infections. The sol-gel method was used to formulate MSNs, which were further optimized using central composite rotatable design (CCRD) by investigating mathematical impact of independent formulation variables such as pH, stirring time, and stirring speed on dependent variables entrapment efficiency (EE) and drug release. The selected optimized MSNs and pure drugs were subjected to comparative in vitro/in vivo antifungal studies, skin irritation, cytotoxicity, and histopathological evaluations. The obtained negatively charged (-23.1), free flowing spherical, highly porous structured MSNs having a size distribution of 300-500 nm were suggestive of high storage stability and improved cell proliferation due to enhanced oxygen supply to cells. The physico-chemical evaluation of SA/KCZ-loaded MSNs performed through powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA) indicates absolute lack of any interaction between formulation components and successful encapsulation of both drugs in MSNs. The EESA, EEKCZ, SA release, and KCZ release varied significantly from 34 to 89%, 36 to 85%, 39 to 88%, and 43 to 90%, respectively, indicating the quadratic impact of formulation variables on obtained MSNs. For MSNs, the skin tolerability and cell viability percentage rate were also having an extraordinary advantage over suspension of pure drugs. The optimized SA/KCZ-loaded MSNs demonstrated comparatively enhanced in vitro/in vivo antifungal activities and rapid wound healing efficacy in histopathological evaluation without any skin irritation impact, suggesting the MSNs potential for the simultaneous codelivery of antifungal and keratolyic agents in sustained release fashion.

Colorectal cancer (CRC) is currently one of the most frequent malignant neoplasms, ranking 3rd in incidence and 2nd in mortality both in the USA and across the world. The pathogenesis of CRC is a complex interaction between genetic susceptibility and environmental factors such as exposure to metals. Therefore, the present study was intended to assess the imbalances in the concentrations of selected essential/toxic elements (Pb, Cr, Fe, Zn, As, Cd, Cu, Se, Ni, and Hg) in the serum of newly diagnosed colorectal carcinoma patients (n = 165) in comparison with counterpart controls (n = 151) by atomic absorption spectrometry after wet-acid digestion method. Serum carcinoembryonic antigen (CEA) of the CRC patients was determined using immunoradiometric method. Body mass index (BMI) which is an established risk factor for CRC was also calculated for patients and healthy controls. Conversely, average Ni (2.721 μg/g), Cd (0.563 μg/g), As (0.539 μg/g), and Pb (1.273 μg/g) levels were significantly elevated in the serum of CRC patients compared to the healthy donors, while the average Se (7.052 μg/g), Fe (15.67 μg/g), Cu (2.033 μg/g), and Zn (8.059 μg/g) concentrations were elevated in controls. The correlation coefficients between the elements in the cancerous patients demonstrated significantly dissimilar communal relationships compared with the healthy subjects. Significant differences in the elemental levels were also showed for CRC types (primary colorectal lymphoma, gastrointestinal stromal tumor, and adenocarcinoma) and CRC stages (stage-I, stage-II, stage-III, and stage-IV) among the patients. Majority of the elements demonstrated perceptible disparities in their levels based on dietary, habitat, gender, and smoking habits of the malignant patients and healthy subjects. Multivariate methods revealed noticeably divergent apportionment among the toxic/essential elements in the cancerous patients than the healthy counterparts. Overall, the study showed significantly divergent distribution and associations of the essential and toxic elemental levels in the serum of the CRC patients in comparison with the healthy donors.

Ferrites are materials of interest due to their broad applications in high technological devices and a lot of research has been focused to synthesize new ferrites. In this regard, an effort has been devoted to synthesize spinel Pr–Ni co-substituted strontium ferrites with a nominal formula of Sr1-xPrxFe2-yNiyO4 (0.0 ≤ x ≤ 0.1, 0.0 ≤ y ≤ 1.0). The cubic structure of pure and Pr–Ni co-substituted strontium ferrite samples calcinated at 1073 K for 3 h has been confirmed through X-ray diffraction (XRD). Average sizes of crystallites (18–25 nm) have been estimated from XRD analysis and nanometer particle sizes of synthesized ferrites have been further verified by scanning electron microscopy (SEM). SEM results have also shown that particles are mostly agglomerated and all the samples possess porosity. It has been observed that at 298 K, the values of resistivity (ρ) increase, while that of AC conductivity, dielectric loss, and dielectric constants decrease with increasing amounts of Pr3+ and Ni2+ ions. The values of dielectric parameters initially decrease with frequency and later become constant and can be explained on the basis of dielectric polarization. Electrochemical impedance spectroscopy (EIS) studies show that the charge transport phenomenon in ferrite materials is mainly controlled via grain boundaries. Overall, synthesized ferrite materials own enhanced resistivity values in the range of 1.38 × 109–1.94 × 109 Ω cm and minimum dielectric losses, which makes them suitable candidates for high frequency devices applications.

During the present investigation, two new sulfonamide-based Schiff base ligands, 4-{[(2-hydroxy-3-methoxyphenyl)methylidene]amino}-N-(1,3-thiazol-2-yl)benzene-1-sulfonamide (L1) and 4-{[1-(2-hydroxyphenyl)ethylidene]amino}-N-(1,3-thiazol-2-yl)benzene-1-sulfonamide (L2), have been synthesized and coordinated with the transition metals (V, Fe, Co, Ni, Cu and Zn). The ligands were characterized by their physical (color, melting point, yield and solubility), spectral (UV–Vis, FT-IR, LC–MS, 1H NMR and 13C NMR) and elemental data. The structures of the metal complexes (1)–(12) were evaluated through their physical (magnetic and conductance), spectral (UV–Vis, FT-IR and LC–MS) and elemental data. The molecular geometries of ligands and their selected metal complexes were optimized at their ground state energies by B3LYP level of density functional theory (DFT) utilizing 6-311+G (d, p) and LanL2DZ basis set. The first principle study has been discussed for the electronic properties, the molecular electrostatic possibilities as well as the quantum chemical identifiers. An obvious transition of intramolecular charge had been ascertained from the occupied to the unoccupied molecular orbitals. The UV–Vis analysis was performed through time-dependent density functional theory (TD-DFT) by CAM-B3LYP/6-311+G (d, p) function. The in vitro antimicrobial activity was studied against two fungal (Aspergillus niger and Aspergillus flavus) and four bacterial (Staphylococcus aureus, Klebsiela pneumoniae, Escherichia coli and Bacillus subtilis) species. The antioxidant activity was executed as antiradical DPPH scavenging activity (%), total iron reducing power (%) and total phenolic contents (mg GAE g−1). Additionally, enzyme inhibition activity was done against four enzymes (Protease, α-Amylase, Acetylcholinesterase and Butyrylcholinesterase). All the synthetic products exhibited significant bioactivity which were found to enhance upon chelation due to phenomenon of charge transfer from metal to ligand.

Nanotechnology is one of the most attractive disciplines ranging from materials science to biomedicine. It is one of the most prominent areas of research for targeting skin melanoma and other diseases. The application of nanomaterials in the field of skin has increased interest in topical targeting to increase the permeation and retention and reduce its side effects. Different types of nanomaterials have been used for the application of skin diseases and cancer. These nanomaterials include carbon-nanotubes, liposomes, nanoemulsion, nano micelles, etc. In the United States and globally, the prevalence of melanoma has had a growing rise throughout the last 50 years. This review seeks to discuss various types of treatment and diagnosis of early-stage skin cancer. There are many skin cancer biomarkers for early detection of this type of cancer. Diagnosis of skin cancer forms a way of traditional approaches, and their weaknesses are discussed. Electrochemical and optical biosensors for the diagnosis and monitoring of skin cancer are also was described. After all, some issues should be addressed and overcome regarding the competition of new techniques in cost and convenience of use.

In the present investigation, brown clay (BC) was modified with didodecyldimethylammonium bromide (DDAB) to produce a sorbent (DDAB-BC), which was characterized and applied for sorption of methylene blue (MB) from aqueous media. BC was functionalized using DDAB by cation exchange of the DDAB moiety with positive ions existing inside the interlayer spaces of the BC. X-ray diffraction (XRD) studies confirmed that the d-spacing of DDAB-BC became wider (3.39 A) than that of BC (3.33 A). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were exploited to explore the functional groups and morphological structure of sorbents, respectively. The Brunauer-Emmett-Teller (BET) surface area, pore volume, and pore diameter of DDAB-BC were determined as 124.6841 m2/g, 0.316780 cm3/g, and 8.75102 nm, respectively. Batch sorption investigations were carried out to determine the optimum experimental conditions, using the one-factor one-time procedure. The sorption of MB on DDAB-BC strongly obeyed the Langmuir isotherm and agreed well with pseudo-second-order kinetics. Sorption of MB onto DDAB-BC showed maximum efficiency (∼98%) and maximum sorption capacity (∼164 mg/g) at optimal values of pertinent factors: dye concentration (100 mg/L), pH (7), and temperature (55 °C). Sorption isothermal studies predicted that removal of MB on DDAB-BC follows multilayer sorption at higher MB dye concentrations and monolayer sorption at lower MB dye concentrations.

In the present work, a novel continuous flow system (CFS) is developed for the preconcentration and determination of Cr (VI) usingPseudomonas aeruginosastatic biomass immobilized onto an effective and low-cost solid support of powdered eggshells. A mini glass column packed with the immobilized biosorbent is incorporated in a CFS for the preconcentration and determination of Cr (VI) from aqueous solutions. The method is based on preconcentration, washing and elution steps followed by colorimetric detection with 1,5-diphenyl carbazide in sulphuric acid. The effects of several variables such as pH, retention time, flow rate, eluent concentration and loaded volume are studied. Under optimal conditions, the CFS method has a linear range between 10 and 100 μg L-1and a detection limit of 6.25 μg L-1for the determination of Cr (VI). The sampling frequency is 10 samples per hour with a preconcentration time of 5 mins. Furthermore, after washing with a 0.1 M buffer (pH 3.0), the activity of the biosorbent is regenerated and remained comparable for more than 200 cycles. Scanning electron microscopy reveals a successful immobilization of biomass on eggshells powder and precipitation of Cr (VI) on the bacterial cell surface. The proposed method proves highly sensitive and could be suitable for the determination of Cr (VI) at an ultra-trace level.

Microemulsions (μEs)-based drug delivery is known to be superior as well as effective due to customizable and easy management, efficiency and capability, and quick drug absorption over a wide range of targets. Herein, two μE formulations were established comprising of clove oil (as oil phase), water (as aqueous phase), Tween-80 (as surfactant), isopropanol, and methanol (as cosurfactant) for formulation A (μE-A) and formulation B (μE-B), respectively, and further used for the encapsulation of an antimuscarinic drug, mirabegron (MBG). Multiple complementary measurements, namely, electrical conductivity (σ), viscosity (η), and optical microscopy, show the existence of phase transition from W/O to O/W μE via intermediate bicontinuous channels. MBG showed long storage stability as well as good solubility i.e. 3.0 and 2.5 wt% at pH 6.4 in optimum μE-A and μE-B, respectively. Furthermore, no apparent aggregation of MBG was observed, as revealed by scanning transmission electron microscopy and peak correlations of IR analysis, suggesting the stability of MBG inside the formulations. Likewise, fluorescence detection senses the interfacial environment of MBG molecules in the examined formulations that could be vital for understanding the mechanism of controlled drug release.

Capped silver nanoparticles (AgNPs) are used in many applications in the biomedical field because of their unique structural flexibility. Herein, a viable chemical reduction synthesis method for AgNPs is described employing ionic surfactants as stabilizing as well as capping agents. Stabilized AgNPs of a quasi-spherical shape were obtained using silver nitrate (AgNO3) as a precursor and sodium borohydride (NaBH4) as a reducing agent under multiple ionic micellar hierarchical approaches. UV-Visible spectroscopy studies showed characteristic single and sharp absorbance peaks in the range 400 to 420 nm, which indicates the absence of the self-aggregation of AgNPs, whereas the FTIR results indicated the surfactant functionalities responsible for the stability of the AgNPs. Micrographs of the as-obtained AgNPs, obtained via electron microscopy (SEM, STEM), demonstrated a fine monomodal collection of spherical nanoparticles of

A new chemiluminescence (CL) system, indigo carmine/glucose/hemin/H2O2, has been found and developed for non-enzymatic detection of indigo carmine (IC) and glucose. The CL response increases linearly with IC concentrations from 3.2 μM to 10 mM and glucose concentrations from 0.06 μM to 3.5 mM. The detection limits are 1.45 μM and 15.0 nM for IC and glucose, respectively. This method allows the determination of glucose in blood and urine after simple dilution. The recoveries for the determination of glucose are between 98.5% and 101.0% in blood and between 98.5% and 101.3% in urine. This method shows good sensitivity, selectivity, simplicity, and is low cost, suggesting its promising broad applications.

In this work, a glutathione (GSH) sensing nano-platform using lucigenin as a fluorescent probe in the presence of MnO2 nanosheets was reported for the first time. Unlike the earlier fluorescent detection systems based on MnO2 nanosheets, which depend on Forster resonance energy transfer (FRET) or the dynamic quenching effect (DQE), the mechanism of the quenching process of MnO2 nanosheets on lucigenin fluorescence was attributed mainly to a static quenching effect (SQE) with a minor contribution of the inner filter effect (IFE). A double exponential fluorescence decay of lucigenin was obtained in various MnO2 nanosheet concentrations as a result of their SQE and IFE. Based on this phenomenon and taking advantage of the redox reaction between GSH and MnO2 nanosheets, we have developed a switch-on sensitive fluorescent method for GSH via the recovery of the MnO2 nanosheet-quenched fluorescence of lucigenin. A good linearity range of 1.0–150.0 μM with a low limit of detection (S/N = 3) of 180.0 nM was achieved, revealing the higher sensitivity for GSH determination in comparison with the previously reported MnO2 nanosheet-based turn-on fluorescent methods. The developed fluorescent nano-platform exhibits excellent selectivity with successful application for GSH detection in human serum plasma, indicating its good practicability for GSH sensing in biological and clinical applications.

Plastics are high molecular mass organic polymers obtained mostly from various hydrocarbons of petrochemicals. Over the past 50 years, plastic materials have been used as a substitution of metal, wood, and paper for many applications because of their excellent features in terms of stability, lightness, low cost, and durability. These polymers are basically nonbiodegradable with only a few exceptions. Poor behavior in communities toward the proper disposal of plastic wastes poses significant threats to the environment. Plastic waste consists of polypropylene, low and high-density polyethylene, polystyrene, polyethylene tetrachloride, polyvinyl chloride, and so forth. Plastic additives of concerns to health and environment include bisphenol A, organotin, triclosan, phthalates, and brominated flame retardants. The current methods used for plastic waste management include incineration, landfilling, chemical, and mechanical recycling. Because plastics are quite recalcitrant type materials, the combined approach using photochemical or thermochemical processes, followed by bioprocessing, is an excellent example of plastic waste management. Biodegradation of plastics is a biochemical process in which a particular compound ultimately breaks into very simpler molecules by the action of enzymes. Plastics are usually biodegraded partly aerobically in soil and compost and anaerobically in landfills and sediments. Aerobic biodegradation produces water and carbon dioxide, while water, carbon dioxide, and methane are produced during anaerobic biodegradation. Biodegradation of plastic waste materials may result in the formation of nanoplastics.