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Dusky cotton bug Oxycarenus hyalinipennis Costa (Hemiptera: Lygaeidae) is a serious polyphagous pest of cotton including other crops. To consider the necessities of growing world population, the use of pesticides have been increased which have resulted insect resistance besides several side effects. Dusky cotton bug (DCB) like other pests also showed resistance to most of the pesticides. To overcome the adverse effects of pesticides, scientists have diverted their attention to develop an ecofriendly approach to combat harmful pest. Nanotechnology is considered as an alternative and an innovative technique for pest control strategy. In the current study characterizations of Azadirachta indica based green synthesized silver nanoparticles (AiAgNPs) have been carried out to investigate the toxicity against 4th, 5th nymphal instars and adult DCB. The AiAgNPs were synthesized by standard protocol and characterized by using various techniques like UV-Vis spectrum, Dynamic light scattering (DLS), Zeta potential, Fourier Transform Infra Red (FTIR) spectrometer, Scanning as well as Transmission Electron Microscopy which confirmed the AiAgNPs biosynthesis. Tukey's HSD test revealed that AiAgNPs nanoformulation at 1250 ppm showed maximum mortality against DCB 4th instar (38.42, 69.21 and 91.95%) followed by 5th instar (34.14, 60.98 and 84.40%) and adult (27.76, 53.88 and 83.15%) post exposure period of (24,48 and 72 h) respectively for each DCB stage as compared to other concentrations used. Probit analysis showed LC50 of tested AiAgNPs 376.04, 485.60 and 560.23 for the 4th, 5th nymphal instars and adult DCB respectively after 72 h post exposure which was positively correlated with older one. The biogenic AiAgNPs proved to be most effective compound and can be used successfully ecofriendly way in IPM program for the management of dusky cotton bug. [ABSTRACT FROM AUTHOR]

The water contamination is a major concern. To address this challenge, facile remediation methods are required. In this connection, outstanding properties and chemical composition of nanomaterials can play an important role. In this study, bismuth molybdenum oxide (Bi4MoO9) nanoparticles were synthesized by a simple hydrothermal method to explore their properties as a photocatalyst and electrocatalyst. The prepared nanoparticles were characterized with zeta sizer, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and fourier transform infrared spectroscopy. The photocatalytic degradation has been studied against industrial dyes i.e., crystal violet (CV) and methyl orange (MO). The result indicated that Bi4MoO9 nanoparticles showed agglomerated morphology with −15 mV surface potential. Nanoparticles carried photo-degradation up to 93.8% and 72% for CV and MO dyes, respectively. In addition to that, chemical oxygen demand (COD) was reduced up to 65% for crystal violet and 53.57% for MO dyes. In addition, electrocatalysis of nanoparticles was studied using cyclic voltammetry. The sensitivity of electrochemical assay for binding ascorbic acid by Bi4MoO9 nanoparticles was achieved as low as 0.02 mM (S/N = 3). The results of the current research provide a new insight to synthesize nanomaterials with interesting chemical composition and to explore the photocatalytic and electrocatalytic properties for multiple applications in environmental and biomedical fields. [ABSTRACT FROM AUTHOR]

Contamination of organic and inorganic compounds has become one of the increasing concerns due to their detrimental effects on the environment and human health. The presence of such organic and inorganic compounds in wastewater poses a challenge in water remediation. Herein, we report successful preparation of Ag@CdO nanocomposite via green methodology to remove Brilliant green from wastewater. The synthesized Ag@CdO nanocomposite was characterized using various analytical studies. SEM–EDS study of Ag@CdO nanocomposite showed an agglomerated spherical shape with signatures of Cd, Ag, and O, and XRD displays characteristic crystallinity. A Zeta potential value − 17.5 mV reveals excellent stability. TEM examination showed an average particle size of 7 nm and 50 nm for bare AgNPs and Ag@CdO nanocomposite, respectively. The maximum photodegradation was obtained in 90 min with Ag@CdO nanocomposite and AgNPs. The maximum degradation efficiency of AgNPs and Ag@CdO nanocomposite was found to be 90% and 96%, respectively, under optimum conditions of temperature; 55 °C and pH 6. In addition, Ag@CdO nanocomposite could be readily regenerated and reused at least 5 times without significant performance loss. Thus, the premeditated photocatalytic Ag@CdO nanocomposite-based platform can further be exploited for remediation of different organic effluents from industrial wastewaters. Furthermore, this work opens new avenues for the enhancement of photocatalytic efficiency of many catalysts already under observation. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci (Genn.) (Homoptera; Aleyrodidae) is one of the utmost destructive pests of field crops. The insect has developed resistance against synthetic pesticides due to repeated and undiscerning usage of pesticides having same mode of action. Solicitation of green synthesized silver nanoparticles (NPs) from Azadirachta indica extract is an emerging biological nanotechnology. It could prove to be a better substitute to synthetic pesticides for the proficient management of B. tabaci. The current study was premeditated for assessment of entomocidal impact of green synthesized silver NPs for the effective control of various life stages of B. tabaci under controlled conditions. Synthesis of the NPs was being done through standard protocols and surface morphology was confirmed by Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). Results revealed that silver nano formulation at 1200 ppm proved the most effective (41.11, 71.11, 80 and 82.22%) reduction in whitefly 3rd instar nymphs after 24, 48, 72 and 96 h of the post-treatment, respectively as compared to other concentrations of silver NPs used. The same concentration of silver NPs was also the most effective against adult population of whitefly, resulted in 37.77, 67.78, 76.66 and 77.77% suppression afterward 24, 48, 72 and 96 h application respectively. Rest of the concentrations gave the lower results. The LC50 data indicated that LC50 = 411.054 ppm concentration were required to kill the 50% of test population of 3rd instar nymphs of whitefly while LC50 = 465.331 ppm were required to kill the 50% of adult population of whitefly after 96 h exposure time. The assimilation of nanoparticles impregnated with biopesticides can be a best option to make the Integrated Pest Management (IPM) of whitefly successful leading to boost up the worth and value of cotton crop in the market. [ABSTRACT FROM AUTHOR]

The safe and targeted delivery of pharmaceutical formulations has relied extensively on synthetic chemistry and other physicochemical approaches. The research paradigm is now especially changing towards green (or environmentally friendly) approaches, and several biopolymer‐based nanocarriers are marked as emerging nanomedicine tools. These have been developed to overcome problems with conventional drug carriers, which induce severe side effects, especially due to non‐specificity with detrimental effects on non‐targeted normal healthy cells. In addition, the phagocytosis of classic nanoparticles (NPs) and their degradation associated with the formation of oxygen radicals by the immune system are significant barriers for drug delivery. In this regard, protein nanocarriers appear as a promising approach to escape unwanted immune reactions. Moreover, these protein‐based NPs are generally non‐toxic, biodegradable, and even cost‐effective. As a less appreciated advantage, the surface properties of proteins are easily modified. There are, however, several challenges and limiting choices to make when choosing the type of modification to enable effective drug delivery. Here, we shed light on the role of protein nanocarriers for enhancing the bioavailability of different anti‐inflammatory drugs, including better macrophage targeting and overcoming biological barriers. This insight helps one to understand their broad utility in the treatment of inflammatory diseases and bridges the gap between naturaltherapeutic products and nanotechnology‐based delivery approaches, creating perhaps an optimal blend to meet some of our most persistent healthcare problems. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanomaterials can be layered together to design hybrid materials. Their exceptional properties can be harnessed to fabricate advanced sensors. In the present study, a novel mass-sensitive sensor has been developed by preparing a hybrid of 2D graphitic carbon nitride nanosheets and molecularly imprinted polymer. 2D graphitic carbon nitride nanosheets (g-C3N4) were synthesized by a microwave-assisted method. Further, a molecularly imprinted polymer (MIP) was designed by free radical polymerization using chloramphenicol as the template analyte. A layered assembly of g-C3N4 and MIP was prepared to modify quartz crystal microbalance (QCM) devices to generate nanointerface. The g-C3N4 nanosheets possessed zeta potential of − 39 mV which indicated strong electrostatic interaction with gold electrodes of QCM, leading to stable adhesion of MIP layers. Morphological investigations by scanning electron microscopy revealed 2D lamellar structures of g-C3N4, with wrinkles and irregular folds. Atomic force microscopy showed the prepared sheet layers were ~ 30 nm thick. The resultant nanointerface was used as a mass-sensitive transducer to detect chloramphenicol. The decrease of the basic frequency of QCM devices upon inclusion of the target analyte generated the sensor signals. A linear relationship of frequency responses was obtained, yielding a detection limit down to 177 µM. Moreover, the prepared sensor gives 98–90% highly specific detection of chloramphenicol compared to its interferents and structural analogs (thiamphenicol and clindamycin). It suggested sucessful application of the prepared hybrid based on layering of 2D materials. The sensor presented here harbors the benefits of excellent sensitivity as well as selective binding. These attributes make 2D hybrid materials a favorable sensor platform for the detection of important environmental molecules. [ABSTRACT FROM AUTHOR]

Cotton production is seriously affected by the prevalent cotton leaf curl disease (CLCuD) that originated from Nigeria (Africa) to various parts of Asia including Pakistan, India, China and Philippines. Due to CLCuD, Pakistan suffers heavy losses approximately 2 billion USD per annum. Numerous reports showed that CLCuD is associated with multiple species of begomoviruses, alphasatellites and a single species of betasatellite, that is 'Cotton leaf curl Multan betasatellite' (CLCuMuB). The most prevalent form of CLCuD is the combination of 'Cotton leaf curl Kokhran virus'-Burewala strain (CLCuKoV-Bur) and CLCuMuB. Thus, the availability of an in-field assay for the timely detection of CLCuD is important for the control and management of the disease. In this study, a robust method using the loop-mediated isothermal amplification (LAMP) assay was developed for the detection of CLCuD. Multiple sets of six primers were designed based on the conserved regions of CLCuKoV-Bur and CLCuMuB-βC1 genes. The results showed that the primer set targeting the CLCuMuB-βC1 gene performed best when the LAMP assay was performed at 58°C using 100 ng of total plant tissue DNA as a template in a 25 µl reaction volume. The limit of detection for the assay was as low as 22 copies of total purified DNA template per reaction. This assay was further adapted to perform as a colorimetric and real-time LAMP assay which proved to be advantageously applied for the rapid and early point-of-care detection of CLCuD in the field. Application of the assay could help to prevent the huge economic losses caused by the disease and contribute to the socio-economic development of underdeveloped countries. [ABSTRACT FROM AUTHOR]

The current pandemic of coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) has challenged healthcare structures across the globe. Although a few therapies are approved by FDA, the search for better treatment options is continuously on rise. Clinical management includes infection prevention and supportive care such as supplemental oxygen and mechanical ventilatory support. Given the urgent nature of the pandemic and the number of companies and researchers developing COVID‐19 related therapies, FDA has created an emergency program to move potential treatments with already approved drugs to patients as quickly as possible in parallel to the development of new drugs that must first pass the clinical trials. In this manuscript, we have reviewed the available literature on the use of sequence‐specific degradation of viral genome using short‐interfering RNA (siRNA) suggesting it as a possible treatment against SARS‐CoV‐2. Delivery of siRNA can be promoted by the use of FDA approved lipids, polymers or lipid‐polymer hybrids. These nanoparticulate systems can be engineered to exhibit increased targetability and formulated as inhalable aerosols. [ABSTRACT FROM AUTHOR]

Nanotechnology provides a great opportunity to design multifunctional materials that can be applied for diverse platforms. As a case study, we prepared bismuth oxychloride nanoplatelets (BiOCl–NPLs) and used as bifunctional interfaces to bind biomarkers, selectively, as well as their biocompatibility potential was assessed. The structures were prepared by a facile and efficiently designed hydrothermal method and possess layered nanoplatelets morphology. The phase composition was investigated by XRD which is in accordance with the tetragonal structure of BiOCl. EDS confirmed the surface elemental composition, whereas, FTIR analysis validated the molecular structure of the prepared structures. BiOCl–NPLs modified interfaces were found remarkable to bind glutathione, an important disease biomarker. The material showed a significant sensing response to bind glutathione, which highlights its diagnostic applications. And the biocompatibility is investigated towards the human colorectal carcinoma cell line (HCT 116) using MTT assay in vitro. Our results showed that BiOCl–NPLs are non-cytotoxic, an important feature for biomedical use. The present study leads a pathway to design dual-functional materials for diagnostic and clinical applications. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT) takes the advantages of Fenton‐type reactions triggered by endogenous chemical energy to generate highly cytotoxic hydroxyl radicals. As a novel modality for cancer treatment, CDT shows minimal invasiveness and high tumor specificity by responding to the acidic and the highly concentrated hydrogen peroxide microenvironment of tumor. The CDT approach for spatiotemporal controllable reactive oxygen species generation exhibits preferable therapeutic performance and satisfying biosafety. In this review article, we summarized the recent advances of stimuli‐activatable nanomedicines for CDT. We also overviewed the strategies for augmenting CDT performance, including increasing the catalytic efficacy through rational design of the nanomaterials, modulating the reaction condition, inputting external energy field, and regulating the tumor microenvironment. Furthermore, we discussed the potential and challenges of stimuli‐activatable nanomedicine for clinical translation and future development of CDT. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic DiseaseNanotechnology Approaches to Biology > Nanoscale Systems in BiologyDiagnostic Tools > In Vivo Nanodiagnostics and Imaging [ABSTRACT FROM AUTHOR]

Unique physical and chemical properties make 1D nanomaterials very attractive and their window of applications is broadened by the addition of biocompatible materials. Similarly, the massive side effects associated with the frequent use of antibiotics make it crucial to analyze the quantity and detect even the subservient amounts of antibiotics in vivo following their administration to patients. The present study describes the one-pot solvothermal approach to produce 1D CuO nanoneedles. Microscopic investigations revealed the presence of nanoneedles of about 8–15 nm in size with negative surface charge (− 30.51 mV). These structures were explored for the targeted detection of the anti-tubercular agent rifampicin. This developed interface showed excellent sensitivity, with the limit of detection as low as 9.4 nM and the limit of quantification as 20 nM. This sensor exhibited good selectivity towards the structural analogs (rifabutene, rifapentine) of the analyte. This study represents the potential of 1D nanomaterial in biomedical applications such as the development of interfaces for online monitoring. [ABSTRACT FROM AUTHOR]

The development of a simplified theranostic system with high-efficiency for multifunctional imaging-guided photodynamic therapy/photothermal therapy (PDT/PTT) is a great challenge. Therefore, a versatile fabrication strategy was introduced to design new Fe3O4-black TiO2 nanocomposites (Fe–Ti NCs). The Fe–Ti NCs exhibit an intense broad light absorption, high photothermal conversion efficiency, inherited phototherapy, and favorable magnetic resonance imaging (MRI) properties. The in vitro results demonstrate synergistic PTT and PDT capability of Fe–Ti NCs under 808 nm irradiation at low concentration and power density. Fe–Ti NCs also show superior phototherapy performance (PTT/PDT) under 671 nm laser irradiation. The confocal microscopy analysis demonstrates reactive oxygen species (ROS)-mediated synergistic phototherapy. Hematological and histological analysis confirms no evident toxicity of Fe–Ti NCs. The in vivo photoinduced tumor ablation capability of Fe–Ti NCs was assessed and monitored, and a rapid increase in temperature (60 ± 2 °C) after being exposed to 808 nm laser at 0.7 W cm−2 for 5 min was observed. Then, the same change in temperature is observed under 671 nm laser at 0.5 W cm−2. Thus, in vitro and in vivo dual-wavelength laser tumor ablation ability of Fe–Ti NCs verified excellent synergistic phototherapy efficacy against tumors. Moreover, Fe–Ti NCs exhibit superparamagnetic behavior, high magnetization value (48 emu g−1), good r2 relaxivity value (38.2 mM−1 s−1), and excellent T2 imaging capability to monitor therapeutic performance. [ABSTRACT FROM AUTHOR]

We report a novel strategy for the fabrication of lecithin-coated gold nanoflowers (GNFs) via single-step design for CT imaging application. Field-emission electron microscope confirmed flowers like morphology of the as-synthesized nanostructures. Furthermore, these show absorption peak in near-infrared (NIR) region at λmax 690 nm Different concentrations of GNFs are tested as a contrast agent in CT scans at tube voltage 135 kV and tube current 350 mA. These results are compared with same amount of iodine at same CT scan parameters. The results of in vitro CT scan study show that GNFs have good contrast enhancement properties, whereas in vivo study of rabbits CT scan shows that GNFs enhance the CT image clearly at 135 kV as compared to that of iodine. Cytotoxicity was studied and blood profile show minor increase of white blood cells and haemoglobin, whereas decrease of red blood cells and platelets. [ABSTRACT FROM AUTHOR]

Niclosamide (NCS) is an oral anthelminthic drug having low solubility and hence low bioavailability. Current investigation shows an approach to fabricate solid lipid nanoparticles (SLNs) of NCS and evaluated for pharmaceutical, in vitro and in vivo characterization. NFM-3 showed particle size 204.2 ± 2.2 nm, polydispersity index 0.328 ± 0.02 and zeta potential -33.16 ± 2 mV. Entrapment efficiency and drug loading capacity were 84.4 ± 0.02% and 5.27 ± 0.03%, respectively. Scanning electron microscopy image indicated that particles were nanoranged. DSC and P-XRD results showed change in physicochemical properties of NCS. FT-IR spectra confirmed compatibility between NCS and excipients. The drug release profile showed sustained release (93.21%) of NCS in 12 h. Different kinetic models showed zero-order kinetics and Case-II transport mechanism. Study showed maximum stability at refrigerated temperature. In vivo pharmacokinetic study showed 2.15-fold increase in NCS peak plasma concentration as solid lipid nanoparticle formulation (NFM-3) compared to commercial product while relative bioavailability was 11.08. Results including in vitro and in vivo release studies of NCS confirmed that SLNs system is suitable to improve oral delivery of NCS with increased aqueous solubility, permeability and finally bioavailability. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) has emerged as one of the promising cancer therapy approaches. However, nanoparticles (NPs) which are used for PTT might be biopersistent and potentially toxic. The current research explores the promising use of Fe3O4 nanoflowers as nontoxic, efficient photothermal, and strong T2 type magnetic resonance imaging (MRI) contrast agents for imaging-guided photothermal cancer therapy. In this study, a facile solvothermal method is used to fabricate PEG-coated Fe3O4 nanoflowers with controllable dimensions. Their successful fabrication, the effect of the reaction parameters, and their magnetic properties are investigated in depth. The therapeutic performance of the Fe3O4 nanoflowers (Fe-NFs) is evaluated and compared with commercially available black TiO2 nanoparticles (b-TiO2) under an 808 nm laser. The photothermal therapy efficiency of the Fe-NFs is observed to be better than that of the reported Fe3O4 nanoparticles. In vitro and in vivo investigation demonstrates that the therapeutic performance of the Fe-NFs is comparable to that of b-TiO2. Moreover, the Fe-NFs show excellent magnetic properties and magnetic resonance imaging capability to monitor therapeutic performance. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of CeO2-TiO2 nanocomposite and its potential application for the visible light-driven photocatalytic degradation of model crystal violet dye as well as real industrial waste water. The ceria-titania (CeO2-TiO2) nanocomposite material was synthesised using facile hydrothermal route without the assistance of any template molecule. As-prepared composite was characterised by SEM, TEM, HRTEM, XRD, XPS for surface features, morphological and crystalline characters. The formed nanostructures were determined to possess crystal-like geometrical shape and average size less than 100 nm. The as-synthesised nanocomposite was further investigated for their heterogeneous photocatalytic potential against the oxidative degradation of CV dye taken as model pollutant. The photo-catalytic performance of the as-synthesised material was evaluated both under ultra-violet as well as visible light. Best photocatalytic performance was achieved under visible light with complete degradation (100%) exhibited within 60 min of irradiation time. The kinetics of the photocatalytic process were also considered and the reaction rate constant for CeO2-TiO2 nanocomposite was determined to be 0.0125 and 0.0662 min−1 for ultra-violet and visible region, respectively. In addition, the as-synthesised nanocomposite demonstrated promising results when considered for the photo-catalytic degradation of coloured industrial waste water collected from local textile industry situated in Faisalabad region of Pakistan. Enhanced photo-catalytic performance of CeO2-TiO2 nanocomposite was proposed owing to heterostructure formation leading to reduced electron-hole recombination. [ABSTRACT FROM AUTHOR]

We report a novel strategy for the fabrication of lecithin-coated gold nanoflowers (GNFs) via single-step design for CT imaging application. Field-emission electron microscope confirmed flowers like morphology of the as-synthesized nanostructures. Furthermore, these show absorption peak in near-infrared (NIR) region at λmax 690 nm Different concentrations of GNFs are tested as a contrast agent in CT scans at tube voltage 135 kV and tube current 350 mA. These results are compared with same amount of iodine at same CT scan parameters. The results of in vitro CT scan study show that GNFs have good contrast enhancement properties, whereas in vivo study of rabbits CT scan shows that GNFs enhance the CT image clearly at 135 kV as compared to that of iodine. Cytotoxicity was studied and blood profile show minor increase of white blood cells and haemoglobin, whereas decrease of red blood cells and platelets. [ABSTRACT FROM AUTHOR]

Famotidine as H2 receptor has antagonistic effects on gastric secretion. Unfortunately, its hydrophobic nature contributes to its variable and poor oral bioavailability. In the current study efforts are being made to fabricate famotidine loaded solid lipid nanoparticles with narrow size distribution. Prepared nanoformulations were pharmaceutically evaluated to confirm the desired boosted oral bioavailability. Famotidine loaded nanoformulation (FFSe-4) showed particle size 111.9±1.3 nm, polydispersity index 0.464±0.03, zeta potential −33.46±2 mV, entrapment efficiency 84±2.7%, and drug loading capacity 2.709±0.13%. Drug-excipients compatibility was confirmed by Fourier transformed infrared spectroscopy. Scanning electron microscopy confirmed spherical shaped, nanosized particles. Differential scanning calorimetry and powder X-ray diffractometry confirmed the change in crystalline nature. Prepared nanoformulation was more stable at refrigerated temperature. In vitro study showed that drug release time is proportional to drug pay load and followed zero order kinetics. Release exponent (n>0.5) confirmed non-Fickian-diffusion mechanism for drug release. In vivo pharmacokinetic studies showed 2.06-fold increase in oral bioavailability of famotidine dispersed in solid lipid nanoparticles compared to commercial product. These results authenticate solid lipid nanoparticles as drug delivery system and propose prolonged release with improved oral bioavailability for famotidine. [ABSTRACT FROM AUTHOR]

In the present work, novel molecularly imprinted polymer porous beads for the selective separation of copper ions have been synthesized by combining two material-structuring techniques, namely, molecular imprinting and oil-in-water-in-oil emulsion polymerization. This method produces monodisperse spherical beads with an average diameter of ∼2-3 mm, in contrast to adsorbents produced in the traditional way of grinding and sieving. Field-emission scanning electron microscopy indicates that the beads are porous in nature with interconnected pores of about 25-50 μm. Brunner-Emmett-Teller analysis shows that the ion-imprinted beads possess a high surface area (8.05 m2/g), and the total pore volume is determined to be 0.00823 cm3/g. As a result of the highly porous nature and ion-imprinting, the beads exhibit a superior adsorption capacity (84 mg/g) towards copper than the non-imprinted material (22 mg/g). Furthermore, selectivity studies indicate that imprinted beads show splendid recognizing ability, that is, nearly fourfold greater selective binding for Cu2+ in comparison to the other bivalent ions such as Mn2+, Ni2+, Co2+, and Ca2+. The imprinted composite beads prepared in this study possess uniform porous morphology and may open up new possibilities for the selective removal of copper ions from waste water/contaminated matrices. [ABSTRACT FROM AUTHOR]

Salmonella enterica serotype Typhi (S. Typhi) is the causative agent of typhoid fever and remains a major health threat in most of the developing countries. The prompt diagnosis of typhoid directly from the patient's blood requires high level of sensitivity and specificity. Some of us were the first to report PCR based diagnosis of typhoid. This approach has since then been reported by many scientists using different genomic targets. Since the number of bacteria circulating in the blood of a patient can be as low as 0.3 cfu ml−1, there is always a room for improvement in diagnostic PCR. In the present study, the role of different types of nanoparticles was investigated to improve the existing PCR based methods for diagnosis and strain typing of S. Typhi (targeting Variable Number of Tandem Repeats [VNTR]) by using optimized PCR systems. Three different types of nanoparticles were used i.e., citrate stabilized gold nanoparticles, rhamnolipid stabilized gold and silver nanoparticles, and magnetic iron oxide nanoparticles. The non-specific amplification was significantly reduced in VNTR typing when gold and silver nanoparticles were used in an appropriate concentration. More importantly, the addition of nanoparticles decreased the non-specificity to a significant level in the case of multiplex PCR thus further validating the reliability of PCR for the diagnosis of typhoid. [ABSTRACT FROM AUTHOR]

Highly efficient visible-light-driven WO3/Fe2(WO4)3·10.7H2O porous microplates have been fabricated for the first time by a simple one-step hydrothermal method using sodium tungstate and iron chloride as precursors. The photocatalyst was characterized by employing X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-VIS absorption, photoluminescence (PL), and Fourier transform infrared spectroscopy (FTIR). From the FESEM and TEM analysis, the size of as-prepared porous microplates was estimated to be ca. 2 μm. The as-prepared sample maintained a high specific surface area (96.906 m2 g−1) and showed remarkably high photocatalytic performance (k = 0.06771 min−1) for the degradation of methyl orange (MO) under visible light irradiation. The improved performance of the product was found to be 3.3 times greater than pure WO3 and about 6.7 times greater than that of P25 TiO2. The enhanced optical absorption in the visible region, large specific surface area, suitable band position and efficient separation of photogenerated electron–hole pairs at the heterojunction interface between the two materials were the key factors involved in the enhancement of the photocatalytic activity. [ABSTRACT FROM AUTHOR]

We have developed a facile, scaled up, efficient and morphology-based novel WO3–g-C3N4 photocatalyst with different mass ratios of WO3 and g-C3N4. It was used for the photodegradation of rhodamine B (RhB) under visible light irradiation and it showed excellent enhanced photocatalytic efficiency as compared to pure g-C3N4 and WO3. The apparent performance of the composite/hybrid was 3.65 times greater than pure WO3 and 3.72 times greater than pure g-C3N4 respectively, and it was also found to be much higher than the previously reported ones. Furthermore, the optical properties of composite samples were evaluated. The bandgap of composite samples lies in the range of 2.3–2.5 eV, which was favourable for photodegradation. The possible mechanism for enhanced catalytic efficiency of the WO3–g-C3N4 photocatalyst is discussed in detail. It was found that the enhanced performance is due to the synergistic effect between the WO3 and g-C3N4 interface, improved optical absorption in the visible region and suitable band positions of WO3–g-C3N4 composites. [ABSTRACT FROM AUTHOR]

Well controlled nanosheets-based hierarchical microspheres (NSHMS) of pure covellite phase CuS were synthesized using a facile PVP assisted solvothermal process. The reaction conditions were optimized using various amounts of PVP to develop unique hierarchical structured hollow microspheres. CuS hollow structures have a bandgap of ~1.97 eV. These mesoporous structures exhibit excellent photocatalytic activity in degradation of organic dyes (Methylene Blue) under natural light in comparison to other structures of copper sulphide. These photocatalysts show extraordinary reusability with over 96.5% degradation of organic dye after 6th cycle. A "bottom-up" assembly was successfully developed to synthesize hollow microspheres with unique and well defined architectures at large scale, which offer a good opportunity to understand the fundamental significance of unusual and complex hierarchical structures for their potential applications. [ABSTRACT FROM AUTHOR]

We report the synthesis of ZnV2O4 spinel oxide novel nanosheets via a template free route to explore its potential hydrogen storage properties for the first time. 2D layered nanostructures are excellent candidates for storage applications. This attracted our interest to synthesize novel spinel oxide nanosheets (NSNs) of ZnV2O4. The maximum value for hydrogen absorption in ZnV2O4 nanosheets at 473 K is 1.36 wt.% and 1.74 wt.% at 573 K, respectively. Our hydrogen storage measurements along ZnV2O4 reveal its superiority over previous reports on hydrogen absorption values concerning oxides, nitrides and chalcogenides. To understand the rate-limiting mechanism, various kinetics models are applied. The calculations show that kinetics is governed by 3D growth with constant interface velocity. The measurements point to ZnV2O4 spinel oxide as a promising hydrogen storage material. PL measurements demonstrate the potential for violet/blue optoelectronic devices. [ABSTRACT FROM AUTHOR]

Fabrication of SnO2nanobelts has been carried out by employing vapour liquid solid (VLS) and vapour solid (VS) mechanism. Nanobelts obtained by VLS mechanism were fabricated at relatively low temperature using Fe powders as a catalyst by means of chemical vapour deposition (CVD) technique. Direct thermal evaporation of SnO2nanobelts was carried out at 1350°C in the atmosphere of Argon gas via VS mechanism. In both cases, ramp rate was adjusted to 10°C/min. The structural, compositional and morphological characterisations of synthesised SnO2nanobelts were conducted by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X‑ray spectroscopy (EDS). Magnetic behaviour of the nanobelts was studied by vibrating sample magnetometer (VSM). Cathodoluminescence (CL) spectra were studied using Renishaw Raman spectroscopy system. The growth of nanobelts is found to be homogeneous and dense. The nanobelts formed by VLS mechanism show ferromagnetic behaviour along with some other exciting results whereas the nanobelts formed by VS mechanism show a diamagnetic behaviour. The observed room temperature ferromagnetism in SnO2nanobelts is superior to other oxides. [ABSTRACT FROM PUBLISHER]

3-D flower like CoNi alloys nanostructures composed of nanorods have been synthesized by template free hydrothermal method at relatively low temperature (120 °C). The detailed characterizations confirm the formation of good crystalline fcc CoNi alloy, average crystallite size of 18.8 ± 1.0 nm, lattice parameter of 3.531 ± 0.01 Å, and the nearly equiatomic composition (Co50Ni50). Highly uniform flower like nano structures are built up with nanorod of diameter about 100 nm and length in range of 200–400 nm. The nanorods (building blocks of flower) have single crystalline nature with [111] preferred growth direction. The concentration of NaOH plays a vital role in formation of alloys and high concentration promotes the formation of CoNi alloy at low temperature. The concentration of NaOH also affects the morphology remarkably by changing the growth/reaction rate of CoNi nanostructures and results in hollow spheres to nanoplate flower of CoNi alloys. Based on the evolution of the morphology of the products, a step wise growth mechanism is rationally proposed for flower like nanostructures by considering the effects of kinetic parameters on growth. Magnetic measurements show Co50Ni50 flower like nanostructure have high saturation magnetization, coercivity, remanent magnetization, and high effective anisotropy constant of value 101.3 emu g−1, 210.5 Oe, 16.2 emu g−1, and 4.457 × 104 J m−3 respectively. The enhancements of coercivity and effective anisotropy constant are attributed to nanoscale effects such as shape/surface anisotropy. [ABSTRACT FROM AUTHOR]

Hollow core–shell η-Fe2O3microspheres exhibit not only superior electrochemical performance as lithium storage electrodes but also excellent sensitivities to trace levels of gases. [ABSTRACT FROM AUTHOR]