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Candida albicans (C. albicans) infection shows a growing burden on human health, and it has become challenging to search for treatment. Therefore, this work focused on the antifungal activity, and cytotoxic effect of biosynthesised nanostructures on human ovarian tetracarcinoma cells PA1 and their corresponding mechanism of cell death. Herein, the authors fabricated advanced biosynthesis of uncoated α‐Fe2 O3 and coated α‐Fe2 O3 nanostructures by using the carbohydrate of Spirulina platensis. The physicochemical features of nanostructures were characterised by UV–visible, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction. The antifungal activity of these nanostructures against C. albicans was studied by the broth dilution method, and examined by 2′, 7′‐dichlorofluorescein diacetate staining. However, their cytotoxic effects against PA1 cell lines were evaluated by MTT and comet assays. Results indicated characteristic rod‐shaped nanostructures, and increasing the average size of α‐Fe2 O3 @ZnO nanocomposite (105.2 nm × 29.1 nm) to five times as compared to α‐Fe2 O3 nanoparticles (20.73nm × 5.25 nm). The surface coating of α‐Fe2 O3 by ZnO has increased its antifungal efficiency against C. albicans. Moreover, the MTT results revealed that α‐Fe2 O3 @ZnO nanocomposite reduces PA1 cell proliferation due to DNA fragmentation (IC50 18.5 μg/ml). Continual advances of green nanotechnology and promising findings of this study are in favour of using the construction of rod‐shaped nanostructures for therapeutic applications. [ABSTRACT FROM AUTHOR]

Sulphonylureas are extensively used in the treatment of type II diabetes; however, these drugs have complications of hypoglycaemia and weight gain. The current study aims at developing a potent antidiabetic drug that has lesser side effects and better management of its associated conditions. Zinc oxide nanoparticles (ZnO NPs) were synthesised using Syzygium cumini seed extract with an average size of 18.92 nm. In vitro studies on rat insulinoma (RIN‐5F) cells revealed that cells treated with synthesised ZnO NPs showed a dose‐dependent increase in insulin secretion. Streptozotocin‐fructose‐induced type II diabetic rats treated with ZnO NPS exhibited a significant reduction (p < 0.01) in the blood glucose levels, total cholesterol, triglycerides, and low‐density lipoprotein levels and increase (p < 0.01) in serum insulin and liver antioxidant enzyme levels proclaiming its role as a hypoglycaemic and hypolipidaemic drug. Treatment of ZnO NPs in diabetic rats exhibited an increased number of beta cells which was responsible for its increased insulin levels and reduced glucose levels. From the overall observations, biosynthesised ZnO NPs exhibited an efficacious hypoglycaemic effect in diabetic rats, so it can be suggested as a potent antidiabetic drug. [ABSTRACT FROM AUTHOR]

This study evaluated the biochemical, molecular, and histopathological mechanisms involved in the hypoglycaemic effect of zinc oxide nanoparticles (ZnONPs) in experimental diabetic rats. ZnONPs were prepared by the sol–gel method and characterised by scanning and transmission electron microscopy (SEM and TEM). To explore the possible hypoglycaemic and antioxidant effect of ZnONPs, rats were grouped as follows: control group, ZnONPs treated group, diabetic group, and diabetic + ZnONPs group. Upon treatment with ZnONPs, a significant alteration in the activities of superoxide dismutase, glutathione peroxidase, and the levels of insulin, haemoglobin A1c, and the expression of cluster of differentiation 4+ (CD4+), CD8+ T cells, glucose transporter type‐4 (GLUT‐4), tumour necrosis factor, and interleukin‐6 when compared to diabetic and their control rats. ZnONPs administration to the diabetic group showed eminent blood glucose control and restoration of the biochemical profile. This raises their active role in controlling pancreas functions to improve glycaemic status as well as the inflammatory responses. Histopathological investigations showed the non‐toxic and therapeutic effect of ZnONPs on the pancreas. TEM of pancreatic tissues displayed restoration of islets of Langerhans and increased insulin‐secreting granules. This shows the therapeutic application of ZnONPs as a safe anti‐diabetic agent and to have a potential for the control of diabetes. [ABSTRACT FROM AUTHOR]

Wound healing has long been recognised as a major clinical challenge for which stablishing more effective wound therapies is necessary. The generation of metallic nanocomposites using biological compounds is emerging as a new promising strategy for this purpose. In this study, four metallic nanoparticles (NPs) with propolis extract (Ext) and one without propolis including ZnO/Ext, ZnO/Ag/Ext, ZnO/CuO/Ext, ZnO/Ag/CuO/Ext and ZnO/W were prepared by microwave method and assessed for their wound healing activity on excision experimental model of wounds in rats. The developed nanocomposites have been characterised by physico‐chemical methods such as X‐ray diffraction, scanning electron microscopy, diffuse reflectance UV–vis spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and Brunauer–Emmett–Teller analyses. The wounded animals treated with the NPs/Ext in five groups for 18 days. Every 6 days, for measuring wound closure rate, three samples of each group were examined for histopathological analysis. The prepared tissue sections were investigated by haematoxylin and Eosin stainings for the formation of epidermis, dermis and muscular and Masson's trichrome staining for the formation of collagen fibres. These findings toughly support the probability of using this new ZnO/Ag/Ext materials dressing for a wound care performance with significant effect compared to other NPs. [ABSTRACT FROM AUTHOR]

In this work, the authors reported the hybrid architecture of carbon nanotube (CNT)–zinc oxide (ZnO) nanowire as a multi‐functional probe in amperometric immunosensor for the detection of urine albumin. Low‐cost substrate such as glass is possible because of novel low‐temperature growth process of CNT/ZnO nanowires as a multi‐function electrode in this sensor. Based on Schottky like behaviour this structure exhibit excellent high current density to achieve higher performance. Measurement of urine albumin is a new way for early detection of diabetic and also low concentration of it in culture media is also considered in order to verify the conversion of stem cells to liver cells. Human albumin serum antibody is used as a selective and sensitive part. The amperometric performance of immunosensor is studied and showed excellent performance for detection of albumin in urine samples. Very high linear range (from 3.3 ng/µl to 3.3 mg/µl) with a correlation coefficient of 0.825 and low detection limit (3.3 ng/µl or 4.96 × 10−8 mol l−1) are the main characteristics of this sensor. Due to the high dynamic range and sensitivity, this sensor was also used in medical diagnosis and biomedical applications. [ABSTRACT FROM AUTHOR]

An extracellular biosynthesis method has been developed to prepare cadmium selenide (CdSe) quantum dots (QDs) with strong fluorescence emission by incubating cheap Cd and Se inorganic salts with Escherichia coli (E.coli) bacteria. Ultraviolet–visible absorption spectra, photoluminescence (PL) spectra, and high‐resolution transmission electron microscopy analysis showed that the biosynthesised CdSe QDs have an average size of 3.1 nm, the excellent optical properties with fluorescence emission around 494 nm, and the good crystallinity. It was found that addition of 80 mg of mercaptosuccinic acid resulted in the formation of CdSe QDs with highest PL intensity. Furthermore, Fourier‐transform infrared spectra of as‐synthesised CdSe QDs confirmed the presence of a surface protein capping layer. The biosynthesised CdSe QDs were incorporated into the yeast cells as illustrated by laser confocal scanning microscopy images, showing a great potential in bio‐imaging and bio‐labelling application. [ABSTRACT FROM AUTHOR]

Antibacterial activity of nanoparticles (NPs) and nanocomposites (NCs) has received wide spread attention in biomedical applications. In this direction, the authors prepared zinc oxide (ZnO), iron oxide (Fe3 O4), and their composite including reduced graphene oxide (rGO) by hydrothermal method. The structural and microstructural properties of the synthesised NPs and NCs were investigated by XRD, FT‐IR, UV‐Vis, TGA, and TEM analysis. PEG‐coated ZnO and Fe3 O4 form in hexagonal wurtzite and inverse spinel structures, respectively. ZnO forms in rod‐shaped (aspect ratio of ∼3) morphology, whereas well‐dispersed spherical‐shaped morphology of ∼10 nm is observed in Fe3 O4 NPs. The ZnO/Fe3 O4 composite possesses a homogeneous distribution of above two phases and shows a very good colloidal stability in aqueous solvent. These synthesised particles exhibited varying antibacterial activity against gram‐positive strain Staphylococcus aureus (S. aureus) and gram‐negative strain Escherichia coli (E. coli). The nanocomposite exhibits a better cidal effect on E. coli when compared to S. aureus when treated with 1 mg/ml concentration. Further, the addition of rGO has intensified the anti‐bacterial effect to a much higher extent due to synergistic influence of individual components. [ABSTRACT FROM AUTHOR]

New drug delivery system (ZnO@CMS) of the redox and pH dual‐stimuli responsive based on colloidal mesoporous silica nanoparticles (CMS) has been designed, in which zinc oxide quantum dots (ZnO QDs) as a capping agent was conjugated on the surface of nanoparticles by amide bonds. The release behaviour of doxorubicin (DOX) as the model drug from ZnO@CMS (ZnO@CMS‐DOX) indicated the redox and pH dual‐stimuli responsive properties due to the acidic dissolution of ZnO QDs and cleavage of the disulphide bonds. The haemolysis and bovine serum albumin adsorption assays showed that the modification of ZnO QDs on the mesoporous silica nanoparticles modified by mercapto groups (CMS‐SH)(ZnO@CMS) had better biocompatibility compared to CMS‐SH. The cell viability and cellular uptake tests revealed that the ZnO@CMS might achieve the antitumour effect on cancer cells due to the cytotoxicity of ZnO QDs. Therefore, ZnO@CMS might be potential nanocarriers of the drug delivery system in cancer therapy. The in vivo evaluation of ZnO@CMS would be carried out in future work. [ABSTRACT FROM AUTHOR]

In this study, the authors have successfully prepared the polyethylene glycol (PEG)‐coated zinc oxide nanoparticles (ZNPs) and studied its effect in pancreatic cancer cells. The authors have observed a nanosized particle with spherical shape. In this study, the authors have demonstrated the cytotoxic effect of ZNP and PZNP in PANC1 cells. To be specific, PZNP was more cytotoxic compared to that of ZNP in PANC1 cancer cells. The authors have further showed that apoptosis is the main mode of cytotoxic activity. It is worth noting that PEGylation of ZNP did not decrease the cell killing activity of zinc particles, whereas it further increases its anticancer effect in the pancreatic cancer cells. The authors have observed a significant upregulation of proapoptotic BAX while expression of antiapoptotic Bcl‐2 was significantly downregulated indicating the potent anticancer effect of zinc nanoparticles. Overall, PEGylation of ZNP could be an effective strategy to improve the stability, while at the same time, its anticancer activity could be enhanced for better therapeutic response. [ABSTRACT FROM AUTHOR]

Due to their unique properties, zinc oxide nanoparticles (ZnO NPs) are invested in many industries, commercial products, and nanomedicine with potential risk for human health and the environment. The present study aims to focus on alterations that might be induced by ZnO NPs in the nephron ultrastructure. Male Wister Albino rats were subjected to ZnO NPs at a daily dose of 2 mg/kg for 21 days. Kidney biopsies were processed to transmission electron microscopy (TEM) and ultrastructural pathology examinations. Exposure to ZnO NPs‐induced ultrastructural alterations in the proximal convoluted tubules (PCTs) and to lesser extent in the distal ones (DCTs), while the loops of Henle were almost not affected. The glomeruli demonstrated dilatation, partial mesangial cells loss, matrix ballooning, slits filtration widening, and basement membrane thickening. Moreover, PCT revealed cytoplasmic necrosis, vacuolation, erosion, and disorganisation of the apical microvilli together with mitochondrial swelling and cristae destruction. The nuclei of the renal cells exhibited nuclear deformity, heterochromatin accumulation, and apoptotic activities. The findings indicate that ZnO nanomaterial have the potential to affect the nephron ultrastructure suggesting alteration in the kidney functions. More work is needed for better understanding the toxicity and pathogenesis of ZnO oxide nanomaterial. [ABSTRACT FROM AUTHOR]

The bio‐green methods of synthesis nanoparticles (NPs) have advantages over chemo‐physical procedures due to cost‐effective and ecofriendly products. The goal of current investigation is biosynthesis of zinc oxide NPs (ZnO‐NPs) and evaluation of their biological assessment. Water extract of Brassica napus pollen [rapeseed (RP)] prepared and used for the synthesis of ZnO‐NPs and synthesised ZnO‐NP characterised using ultraviolet–visible, X‐ray diffraction, Fourier‐transform infrared spectroscopy, field emission scanning electron microscope and transmission electron microscope. Antioxidant properties of ZnO‐NPs, cytotoxic and pro‐apoptotic potentials of NPs were also evaluated. The results showed that ZnO‐NPs have a hexagonal shape with 26 nm size. ZnO‐NPs synthesised in RP (RP/ZnO‐NPs) exhibited the good antioxidant potential compared with the butylated hydroxyanisole as a positive control. These NPs showed the cytotoxic effects against breast cancer cells (M.D. Anderson‐Metastasis Breast cancer (MDA‐MB)) with IC50 about 1, 6 and 6 μg/ml after 24, 48 and 72 h of exposure, respectively. RP/ZnO‐NPs were found effective in increasing the expression of catalase enzyme, the enzyme involved in antioxidants properties of the cells. Bio‐green synthesised RP/ZnO‐NPs showed antioxidant and cytotoxic properties. The results of the present study support the advantages of using the bio‐green procedure for the synthesis of NPs as an antioxidant and as anti‐cancer agents. [ABSTRACT FROM AUTHOR]

Chondrosarcoma is the second‐most malignant cancer of the bone and routine treatments such as chemotherapy and radiotherapy have not responded to the treatment of this cancer. Due to the resistance of chondrosarcoma to radiotherapy, the combination of therapeutic methods has been considered in recent years. In this study, a novel combination approach is used that allows photodynamic therapy to be activated by X‐rays. The synthesis of Mn‐doped zinc sulphide (ZnS) quantum dots was carried out and chlorin e6 photosensitiser attached by covalent and non‐covalent methods and their application as an intracellular light source for photodynamic activation was investigated. The toxicity of each nanoparticles was evaluated on chondrosarcoma cancer cells (SW1353) before and after radiation. Also, the effect nanoparticle‐photosensitiser conjugated type was investigated in the therapeutic efficacy. The characterisation test (SEM, TEM, EDS, TGA, XRD and ICP analyses) was shown successful synthesis of Mn‐doped ZnS quantum dots. Chondrosarcoma cancer cell viability was significantly reduced when cells were treated with MPA‐capped Mn‐doped ZnS quantum dots‐chlorin e6 with spermine linker and with covalent attachment (P ≤ 0.001). These results indicate that X‐ray can activate the quantum dot complexes for cancer treatment, which can be a novel method for treatment of chondrosarcoma. [ABSTRACT FROM AUTHOR]

In this study, the ketoconazole‐conjugated zinc oxide (ZnO) nanoparticles were prepared in a single‐step approach using dextrose as an intermediate compound. The physical parameters confirmed the drug conjugation with ZnO and their size was around 70–75 nm. The drug loading and in vivo drug release studies indicated that the –CHO group from the dextrose increase the drug loading up to 65% and their release kinetics were also studied. The anti‐fungal studies indicated that the prepared nanoparticles exhibit strong anti‐fungal activity and the minimum concentration needed is 10 mg/ml. The nanoparticles loaded semi‐solid gel was prepared using carbopol, methylparaben, propyl paraben and propylene glycol. The in vitro penetration of the ketoconazole‐conjugated nanoparticles was studied using the skin. The results indicated that the semi‐solid gel preparations influenced the penetration and also favoured the accumulation into the skin membrane. The veterinary clinical studies indicated that the prepared gel is highly suitable for treatment of Malassezia. [ABSTRACT FROM AUTHOR]

Nanobiotechnology is one of the emerging fields and its interventions in agriculture is been attracting the scientific community. Herein, the authors first to report on control of groundnut bruchid (Caryedon serratus O.) using nanoscale zinc oxide (ZnONPs) particles and nanoscale chitosan (CNPs) particles‐based Azadirachtin formulations. ZnONPs and CNPs were prepared using sol–gel and ion tropic gelation techniques, respectively. Neem seed kernel extract (NSKE) 5% and Neem oil (3000 and 1000 ppm) were encapsulated using the prepared nanoscale materials and characterised using the techniques such as dynamic light scattering, high‐resolution transmission electron microscopy. Spherical‐shaped nanoparticles were formed after encapsulation with the required bio‐materials (ZnONPs 33.1 nm; CNPs 78.8 nm; neem oil encapsulated (3000 ppm) ZnONPs 182.9 nm; NSKE encapsulated ZnONPs 84.9 nm) and observed that the particles are stable (52.3 mV for ZnONPs, −36.2 mV for CNPs, −43.0 mV for neem oil encapsulated (3000 ppm) ZnONPs and −39.4 mV for NSKE encapsulated ZnONPs). NSKE encapsulated CNPs were able to contain groundnut bruchid up to 180 days with 54.61% weight loss compared to other formulations tested. Thus biomaterial encapsulated nanoscale material formulations are proved to be effective in controlling stored grain pests to reduce huge economic losses. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are gaining special interest due to their recent applications as antimicrobial agents to defeat the massive threat of resistant pathogens. This study focused on the utilisation of Streptomyces isolate S12 purified from waste discharge soil in the biological synthesis of silver (Ag), selenium (Se), and zinc oxide (ZnO) NPs. The isolate S12 was related to Streptomyces enissocaesilis according to 16S rRNA sequence analysis, morphological characteristics, and biochemical reactions. The cell‐free supernatant has been used for the synthesis of Ag, Se, and ZnO NPs. The synthesised NPs were characterised using ultraviolet–visible spectroscopy, dynamic light scattering (DLS), transmission electron microscopy, and Fourier transform infrared spectroscopy. The biogenic NPs were evaluated for antimicrobial effects against different Gram‐positive and Gram‐negative resistant isolates using the broth microdilution method. They showed antibacterial effect against standard and resistant isolates; Bacillus cereus, Staphylococcus aureus ATCC 29213, S. aureus S1.1, methicillin resistant S. aureus (MRSA 303, 402 and 807), Escherichia coli ATCC 12435, E. coli E7, Klebsiella pneumoniae ATCC 51503, K. pneumoniae K5, K112, Pseudomonas aeruginosa PAO1, and P. aeruginosa P8. This study showed the green synthesis of various NPs using Streptomyces isolate S12 which demonstrated diverse activities against multi‐drug resistant isolates. [ABSTRACT FROM AUTHOR]

The increasing use of nanoparticles and their occurrence in the environment has made it imperative to elucidate their impact on the environment. Although several studies have advanced the authors' understanding of nanoparticle–plant interactions, their knowledge of the exposure of plants to nanoparticles and their effects on edible crop plants remain meager and is often paradoxical. The aim of this study was to increase their knowledge on the effect of zinc oxide (ZnO) nanoparticles on eggplant seed germination and seedling growth. ZnO nanoparticles had a negative effect on the growth of eggplant in plant tissue‐culture conditions, as the growth of seedlings decreased with the increase in the concentration of ZnO nanoparticles. In contrast, ZnO nanoparticles enhanced eggplant growth under greenhouse conditions. The accumulation of ZnO nanoparticles in various parts of eggplant was observed through scanning electron microscopy of both plant tissue‐culture and greenhouse‐raised eggplant seedlings. To the best of their knowledge, this is the first study to report on ZnO nanoparticle accumulation in eggplant and its effect on seed germination and seedling growth. [ABSTRACT FROM AUTHOR]

The development of antibiotic resistance among hospital pathogens has provided a great need for new antimicrobial agents. Zinc oxide nanoparticles (ZnO NPs) in combination with various antibiotics can act as a reducing agent for antibiotic resistance. The aim of this study was to investigate the influence and the mechanism of ZnO NPs on the antimicrobial activity of ciprofloxacin (CP) and ceftazidime (CAZ) against Enterococcus faecalis (E. faecalis) and Acinetobacter baumannii (A. baumannii) bacteria in acidic conditions (pH 5.5). ZnO NPs were synthesised using the solvothermal method and characterised. The MIC90 value of ZnO NPs against A. baumannii was 0.25 mg ml−1 and its highest growth‐inhibitory activity was observed at 0.125 mg ml−1 for E. faecalis. The Fourier transform infrared spectroscopy spectra of ZnO NPs treated with antibiotics showed the interaction between ZnO NPs and each of the two antibiotics. ZnO NPs at a sub‐inhibitory concentration had no effect on the antibacterial activity of CP and CAZ against E. faecalis and CP against A. baumannii. The action mechanism of ZnO NPs for enhancing the antibacterial efficacy of CAZ against A. baumannii was evaluated. ZnO NPs caused to increase in the antibacterial activity of CAZ against A. baumannii, possibly through the release of Zn2+ and increasing of membrane permeability. [ABSTRACT FROM AUTHOR]

Currently, the evolution of green chemistry in the synthesis of nanoparticles (NPs) with the usage of plants has captivated a great response. In this study, in vitro plantlets and callus of Silybum marianum were exploited as a stabilising agent for the synthesis of zinc oxide (ZnO) NPs using zinc acetate and sodium hydroxide as a substitute for chemical method. The contemporary investigation defines the synthesis of ZnO NPs prepared by chemical and bio‐extract‐assisted methods. Characterisation techniques such as X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and energy dispersive X‐ray were used to confirm the synthesis. Although chemical and bio‐assisted methods are suitable choices for NPs synthesis, the bio‐assisted green assembly is advantageous due to superior stability. Moreover, this report describes the antibacterial activity of the synthesised NPs against standard strains of Klebsiella pneumonia and Bacillus subtilis. [ABSTRACT FROM AUTHOR]

In the present study, silver (Ag) and Ag–zinc oxide (ZnO) composite nanoparticles (NPs) were synthesised and studied their wound‐healing efficacy on rat model. Ultraviolet–visible spectroscopy of AgNPs displayed an intense surface plasmon (SP) resonance absorption at 450 nm. After the addition of aqueous Zn acetate solution, SP resonance band has shown at 413.2 nm indicating a distinct blue shift of about 37 nm. X‐ray diffraction analysis Ag–ZnO composite NPs displayed existence of two mixed sets of diffraction peaks, i.e. both Ag and ZnO, whereas AgNPs exhibited face‐centred cubic structures of metallic Ag. Scanning electron microscope (EM) and transmission EM analyses of Ag–ZnO composite NPs revealed the morphology to be monodispersed hexagonal and quasi‐hexagonal NPs with distribution of particle size of 20–40 nm. Furthermore, the authors investigated the wound‐healing properties of Ag–ZnO composite NPs in an animal model and found that rapid healing within 10 days when compared with pure AgNPs and standard drug dermazin. [ABSTRACT FROM AUTHOR]

Mounting‐up economic losses to annual crops yield due to micronutrient deficiency, fertiliser inefficiency and increasing microbial invasions (e.g. Xanthomonas cempestri attack on tomatoes) are needed to be solved via nano‐biotechnology. So keeping this in view, the authors' current study presents the new horizon in the field of nano‐fertiliser with highly nutritive and preservative effect of green fabricated zinc oxide‐nanostructures (ZnO‐NSs) during Lycopersicum esculentum (tomato) growth dynamics. ZnO‐NS prepared via green chemistry possesses highly homogenous crystalline structures well‐characterised through ultraviolet and visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscope. The ZnO‐NS average size was found as small as 18 nm having a crystallite size of 5 nm. L. esculentum were grown in different concentrations of ZnO‐NS to examine the different morphological parameters includes time of seed germination, germination percentage, the number of plant leaves, the height of the plant, average number of branches, days count for flowering and fruiting time period along with fruit quantity. Promising results clearly predict that bio‐fabricated ZnO‐NS at optimum concentration resulted as growth booster and dramatically triggered the plant yield. [ABSTRACT FROM AUTHOR]

In this report, a novel wound dressing material has been woven by electrospinning technique and tested for its various properties. For the nanofibre mat, a mixture of polyurethane (PU) and soy protein isolate (SPI) was electrospun in conjugation with zinc oxide nanoparticles (ZnO Nps) and ciprofloxacin hydrochloride (CipHCl) to produce fibrous mats viz. PU/SPI/ZnO and PU/SPI/CipHCl. An optimum ratio (1 : 1) of PU/SPI was used as suitable polymeric ratio in order to produce homogenous nanofibres without beads having an average diameter in the range of 300–350 nm. The electrospun nanofibre‐based mats were characterised using X‐ray diffraction, Fourier transform infrared spectroscopy, ultraviolet‐visible spectroscopy, thermogravimetric analysis and scanning electron microscope. The mechanical properties of the nanofibrous mats were tested using universal testing machine. The wettability analysis was done using the contact angle measurement based on the sessile drop test. This study revealed that the electrospun PU/SPI‐based nanofibres are non‐sensitizing, non‐allergic and non‐toxic and that it can be used as a peculiar wound healing material. [ABSTRACT FROM AUTHOR]

To grapple with multidrug resistant bacterial infections, implementations of antibacterial nanomedicines have gained prime attention of the researchers across the globe. Nowadays, zinc oxide (ZnO) at nano‐scale has emerged as a promising antibacterial therapeutic agent. Keeping this in view, ZnO nanostructures (ZnO‐NS) have been synthesised through reduction by P. aphylla aqueous extract without the utilisation of any acid or base. Structural examinations via scanning electron microscopy (SEM) and X‐ray diffraction have revealed pure phase morphology with highly homogenised average particle size of 18 nm. SEM findings were further supplemented by transmission electron microscopy examinations. The characteristic Zn–O peak has been observed around 363 nm using ultra‐violet–visible spectroscopy. Fourier‐transform infrared spectroscopy examination has also confirmed the formation of ZnO‐NS through detection of Zn–O bond vibration frequencies. To check the superior antibacterial activity of ZnO‐NS, the authors' team has performed disc diffusion assay and colony forming unit testing against multidrug resistant E. coli, S. marcescens and E. cloacae. Furthermore, protein kinase inhibition assay and cytotoxicity examinations have revealed that green fabricated ZnO‐NS are non‐hazardous, economical, environmental friendly and possess tremendous potential to treat lethal infections caused by multidrug resistant pathogens. [ABSTRACT FROM AUTHOR]

A facile and green synthesis of the Ag/ZnO nanocomposite by extract of Valeriana officinalis L. root in the absence of any stabiliser or surfactant has been reported in this work. The green synthesised Ag/ZnO nanocomposite was characterised by Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X‐ray spectroscopy (EDS), elemental mapping, Fourier‐Transform infrared (FT‐IR), X‐ray diffraction analysis (XRD) and UV‐Vis spectroscopy. According to SEM and TEM images, the Ag and ZnO particles are spherical with diameters of less than 20 and 40–50 nm, respectively. The Ag NPs/ZnO nanocomposite proved to be an effective catalyst in the reduction of various dyes including methyl orange (MO), Congo red (CR) and methylene blue (MB) in the presence of NaBH4 in aqueous media at ambient temperature. A maximum degradation (100author="apfister" timestamp="20170720T152916+0100" content="&amp;"author="apfister" timestamp="20170720T152914+0100"%) of dyes was performed using Ag/ZnO nanocomposite. The extraordinary performance of the prepared Ag/ZnO nanocomposite is attributed to the synergetic effect induced by both ZnO and Ag NPs in the catalytic degradation of organic dyes. The catalyst could be reused and recovered several times with no significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

The authors report a controlled synthesis of biocompatible ZnO and acarbose‐capped nanohybrids, and examined the inhibition activities of these nanosystems with human salivary α ‐amylase (HSA) activity. XRD measurements reveal ZnO present in wurtzite phase with hexagonal structure. The average size of ZnO particles for the two studied nanosystems was estimated to lie between 10 to 12 nm using Scherrer equation. These particles depict the onset of absorption at about 320 nm and the band‐gap emission at about 370 nm, which are fairly blue shifted as compared with the bulk ZnO and have been understood due to the size quantisation effect. The inhibitory action of thioglycerol capped ZnO nanoparticles (SP1) and acarbose drug (used for diabetes type II) capped ZnO (SP2) for HSA was observed to 61 and72%, respectively. The inhibition activity of the SP1 alone was found to be very similar to that of acarbose and the coating of these particles with drug (SP2) demonstrated an enhancement in inhibition activity of the enzyme by about 30%. From the inhibition studies, it is confirmed that these nanosystems showed better inhibition activity at physiological temperature and pH. These nanosystems are projected to have potential applications in diabetes type II control. [ABSTRACT FROM AUTHOR]

The present study focus on optical sensing of breast cancer antigen 15.3 (CA 15.3) using cadmium sulphide quantum dot (CdS‐QD) in saline and serum samples spiked with antigen. The surface of CdS‐QD was modified by cysteamine capping followed by tagging of CA 15.3 antibody. The samples were characterised using UV‐visible absorption spectroscopy (UV‐VIS Spectroscopy), Fourier transform infrared spectroscopy (FTIR), high‐resolution transmission electron microscopy (HRTEM) attached with energy‐dispersive X‐ray spectroscopy, phase contrast inverted epi‐fluorescence microscopy and photoluminescence (PL) spectrophotometry (EDS). The CdS‐QD showed a mean diameter of 3.02 ± 0.6 nm. The complex formed after antigen‐antibody interaction resulted in distinguishable optical and fluorescence intensity with respect to varying concentration of antigen. The PL study revealed that CA 15.3 antibody labelled CdS QD can detect CA 15.3 tumour marker even at very low concentration of 0.002 KU/L with a constant response time of 15 min. This study clearly indicates that detection of CA 15.3 at low concentration is possible using surface modified CdS QD in serum samples and can find immense applications in biosensor development for detection of breast cancer marker similar to various automated detection kits available in market. [ABSTRACT FROM AUTHOR]

In this study, an in‐situ approach was used to synthesise zinc oxide nanoparticles on the surface of cotton fabric. The effect of alkaline pre‐ and after‐treatment and Zn2+ concentration was studied on the morphological, structural, thermal, photocatalytic, and antibacterial properties of loaded cotton fabrics. Scanning electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffractometer, thermogravimetric analysis, and attenuated total reflection Fourier transform infrared spectrometer were used to characterise the properties of loaded cotton fabrics. Alkaline after‐treatment of cotton fabric presented more dispersed zinc oxide nanoparticles, and an increase in Zn2+ concentration led to form agglomerated nanoparticles on the surface of cotton fibres. The loaded cotton fabrics with zinc oxide nanoparticles presented an inhibition zone against Staphylococcus aureus and Escherichia coli. In addition, the stain of methylene blue on the surface of loaded samples was degraded after irradiated under visible light. [ABSTRACT FROM AUTHOR]

To evaluate the time effect on the distribution of zinc oxide nanoparticles (ZnO NPs) in tissues from rats and mice, a search on the PubMed, Embase, SpringerLink, Scopus, Science Direct, Cochrane, CNKI, Wanfang, and vip databases up to September 2014 was performed, followed by screening, data extraction, and quality assessment. Thirteen studies were included. At 24 h, Zn content was mainly distributed in the liver, kidney, and lung. At ≥7 days, Zn content was mainly distributed in the liver, kidney, lung, and brain. ZnO NPs are readily deposited in tissues. Furthermore, as time increases, Zn content decreases in the liver and kidney, but increases in the brain. [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles is superior to physical and chemical methods as it is environment‐friendly and cost‐effective. The present study was carried out for inducing nanoparticles synthesis by zinc nitrate in the leaves extracts of olive. Further leaves extracts were evaluated for antiradical scavenging activity by 1, 1‐diphenyl‐2‐picryl‐hydrazyl assay. Morphological and structural properties of the synthesised ZnO nanoparticles have been characterised using UV‐Vis spectrophotometer, FTIR, TEM, XRD and dynamic light scattering (DLS) analysis. Further, zinc oxide nanoparticles were evaluated for antiradical scavenging activity by capacity of total antioxidant assay. Synthesised ZnO nanoparticles were confirmed by the absorption maxima at the wavelength of 370 nm. TEM image revealed that ZnO nanoparticles were spherical with average size 41 nm. FTIR investigation suggested that the flavonoids, glycosides, proteins and phenols molecules can play an important role in the stabilisation of ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

The fluorescence labelling of plant hormone binding sites is an important analytical technique in research on the molecular mechanisms of plant hormone activities. The authors synthesised a jasmonic acid (JA)‐conjugated ZnS:Mn quantum dot (QD) probe, with a cubic structure and average hydrodynamic sizes of about 17.0 nm. The maximum fluorescence emission of the probe was recorded at about 585 nm. The probe was used for fluorescence labelling of JA binding sites in mung bean seedling tissues. Analysis revealed that the probe exhibited high selectivity to JA binding sites and good performance in eliminating interference from background fluorescence in plant tissues. In addition, the probe did not exhibit any apparent biotoxicity, and is much more suitable than probes constructed from CdTe QDs for the analysis of biological samples. [ABSTRACT FROM AUTHOR]

Antibacterial and antifungal activities of zinc oxide nanoparticles (ZnO NPs) were investigated against infectious microorganisms. ZnO NPs were prepared by wet chemical precipitation method varying the pH values. Particle size and morphology of the as‐prepared ZnO powders were characterised by X‐ray diffraction, Fourier transform infrared spectroscopy and transmission electron microscope. The zone of inhibition by NPs ranged from 0 to 17 mm. The lowest minimum inhibitory concentration value of NPs is 25 µg.ml−1 against Staphylococcus epidermidis. These studies demonstrate that ZnO NPs have wide range of antimicrobial activities towards various microorganisms. The results obtained in the authors' study indicate that the inhibitory efficacy of ZnO NPs is significantly dependent on its chosen concentration and size. Significant inhibition in antibacterial response was observed for S. epidermidis when compared with control antibiotic. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are one of the first nanotechnologies to be integrated with the biological sciences that used for imaging or tracking macromolecules/cells in cell/tissue. Because of QDs are important in biomedical and biological applications, identify a variety of synthesis methods to produce QDs with different characteristics also is particularly important. Hence, in this review the authors discussed three methods for synthesis of heavy metal chalcogenide‐based QDs for use in biomedical field: (i) Organometallic method for synthesis of QDs consists of three components: precursors, organic surfactants and solvents. The authors also discussed water‐solubilisation strategies of synthesised QDs including encapsulation and ligand exchange. (ii) Aqueous synthesis technique using short‐chain thiols as stabilising agents is a useful alternative to organometallic synthesis of CdSe, CdS and CdTe QDs. (iii) The third method discussed in this article for QDs synthesis involves the utilise of microorganisms to prepare QDs with controlled size, shape, chemical composition and functionality. The authors also discussed recently new methods for the synthesis of the appropriate QDs for use in biology. In addition, attachment of biomolecules such as antibodies, oligonucleotides on the surface of QDs for specific targeting and different opinions about toxicity of QD have been studied. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate one of the biological sensory applications (fluorescence resonance energy transfer (FRET)) that has astonishing influence on implementation of the bio‐medical assays. For the first time, in this study, the new inorganic modified nanoparticle structure (quantum‐dot quantum‐well (QDQW) heteronanocrystal) is used as donor particle. By considering the mentioned structure, the authors can easily manipulate the donor emission spectrum and all parameters of FRET, such as overlapping between the donor emission and acceptor absorption. In this procedure, the Förster radius can be completely controlled. Moreover, the quantum confinement effects, including the strong‐confinement and the weak‐confinement regime, are investigated for FRET essential variables. As a main goal of this study, the authors will mathematically explore the influences of perturbation on the intrinsic parameters of nanoparticles (lifetime and bandwidth of emission spectrum) and on the sensitivity of FRET. It can be revealed that the presence of perturbation in nanoparticle has a devastating influence on biological assay characteristics, which will be probe in presented simulations. Furthermore, the physically analysing of QDQW heteronanocrystal structure is performed by the accurate eight‐band K.P theory and finite‐element method. [ABSTRACT FROM AUTHOR]

ZnO (Zincite) nanoparticle has many industrial applications and is mostly produced by chemical reactions, usually prepared by decomposition of zinc acetate or hot‐injection and heating‐up method. Synthesis of semi‐conductor nanoparticles such as ZnS (Sphalerite) by ultrasonic was previously reported. In this work, high‐zinc tolerant bacteria were isolated and used for nano zinc production. Among all isolated microorganisms, a gram negative bacterium which was identified as Brevundimonas diminuta could construct nano magnetite zinc oxide on bacterial surface with 22 nm in size and nano zinc with 48.29 nm in size. A piece of zinc metal was immersed in medium containing of pure culture of B. diminuta. Subsequently, a yellow‐white biofilm was formed which was collected from the surface of zinc. It was dried at room temperature. The isolated biofilm was analysed by X‐ray diffractometer. Interestingly, the yield of these particles was higher in the light, with pH 7 at 23°C. To the best of the authors knowledge, this is the first report about the production of nano zinc metal and nano zinc oxide that are stable and have anti‐bacterial activities with magnetite property. Also ZnS (sized 12 nm) produced by Pseudomonas stutzeri, was studied by photoluminescence and fluorescent microscope. [ABSTRACT FROM AUTHOR]