Displaying publications 1 - 20 of 381 in total

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  1. Yusuf I, Ahmad SA, Phang LY, Yasid NA, Shukor MY
    3 Biotech, 2019 Jan;9(1):32.
    PMID: 30622870 DOI: 10.1007/s13205-018-1555-x
    The ability of gellan gum-immobilised cells of the heavy metal-tolerant bacterium Alcaligenes sp. AQ05-001 to utilise both heavy metal-free and heavy metal-polluted feathers (HMPFs) as substrates to produce keratinase enzyme was studied. Optimisation of the media pH, incubation temperature and immobilisation parameters (bead size, bead number, gellan gum concentration) was determined for the best possible production of keratinase using the one-factor-at-a-time technique. The results showed that the immobilised cells could tolerate a broader range of heavy metal concentrations and produced higher keratinase activity at a gellan gum concentration of 0.8% (w/v), a bead size of 3 mm, bead number of 250, pH of 8 and temperature of 30 °C. The entrapped bacterium was used repeatedly for ten cycles to produce keratinase using feathers polluted with 25 ppm of Co, Cu and Ag as substrates without the need for desorption. However, its inability to tolerate/utilise feathers polluted with Hg, Pb, and Zn above 5 ppm, and Ag and Cd above 10 ppm resulted in a considerable decrease in keratinase production. Furthermore, the immobilised cells could retain approximately 95% of their keratinase production capacity when 5 ppm of Co, Cu, and Ag, and 10 ppm of As and Cd were used to pollute feathers. When the feathers containing a mixture of Ag, Co, and Cu at 25 ppm each and Hg, Ni, Pb, and Zn at 5 ppm each were used as substrates, the immobilised cells maintained their operational stability and biological activity (keratinase production) at the end of 3rd and 4th cycles, respectively. The study indicates that HMPF can be effectively utilised as a substrate by the immobilised-cell system of Alcaligenes sp. AQ05-001 for the semi-continuous production of keratinase enzyme.
    Matched MeSH terms: Silver
  2. Lim MM, Sultana N
    3 Biotech, 2016 Dec;6(2):211.
    PMID: 28330282 DOI: 10.1007/s13205-016-0531-6
    The development of nano-sized scaffolds with antibacterial properties that mimic the architecture of tissue is one of the challenges in tissue engineering. In this study, polycaprolactone (PCL) and PCL/gelatine (Ge) (70:30) nanofibrous scaffolds were fabricated using a less toxic and common solvent, formic acid and an electrospinning technique. Nanofibrous scaffolds were coated with silver (Ag) in different concentrations of silver nitrate (AgNO3) aqueous solution (1.25, 2.5, 5, and 10 %) by using dipping method, drying and followed by ultraviolet (UV) photoreduction. The PCL/Ge (70:30) nanofibrous scaffold had an average fibre diameter of 155.60 ± 41.13 nm. Characterization showed that Ag was physically entrapped in both the PCL and PCL/Ge (70:30) nanofibrous scaffolds. Ag(+) ions release study was performed and showed much lesser release amount than the maximum toxic concentration of Ag(+) ions in human cells. Both scaffolds were non-toxic to cells and demonstrated antibacterial effects towards Gram-positive Bacillus cereus (B. cereus) and Gram-negative Escherichia coli (E. coli). The Ag/PCL/Ge (70:30) nanofibrous scaffold has potential for tissue engineering as it can protect wounds from bacterial infection and promote tissue regeneration.
    Matched MeSH terms: Silver Nitrate
  3. Alli YA, Ejeromedoghene O, Oladipo A, Adewuyi S, Amolegbe SA, Anuar H, et al.
    ACS Appl Bio Mater, 2022 Nov 21;5(11):5240-5254.
    PMID: 36270024 DOI: 10.1021/acsabm.2c00670
    Quaternary Trimethyl Chitosan (QTMC) and QTMC-Silver Nanoparticles (QTMC-AgNPs) have been synthesized, characterized, and tested as antibacterial agents against Staphylococcus aureus, Escherichia coli, and two plant fungi (Sclerotium rolfsil and Fusarium oxysporum). The as-prepared water-soluble QTMC was in situ reacted with silver nitrate in the presence of clean compressed hydrogen gas (3 bar) as a reducing agent to produce QTMC-AgNPs. UV-vis, ATR-FTIR, HR-TEM/SEM, XPS, DLS, XRD, and TGA/DTG were employed to assess the optical response, morphology/size, surface chemistry, particle size distribution, crystal nature, and thermal stability of the synthesized QTMC-AgNPs, respectively. The as-prepared QTMC-AgNPs were quasi-spherical in shape with an average particle size of 12.5 nm, as determined by ImageJ software utilizing HR-TEM images and further validated by DLS analysis. The development of crystalline nanoparticles was confirmed by the presence of distinct and consistent lattice fringes with an approximate interplanar d-spacing of 2.04 nm in QTMC-AgNPs. The QTMC-AgNPs exhibited significant antibacterial activity with a clear zone of inhibition of 30 mm and 26 mm around the disks against E. coli and S. aureus, respectively. In addition, QTMC-AgNPs showed highly efficient antifungal activity with 100% and 76.67% growth inhibition against two plant pathogens, S. rolfsii and F. oxysporum, respectively, whereas QTMC revealed no impact. Overall, QTMC-AgNPs showed a promising therapeutic potential and,thus, can be considered for drug design rationale.
    Matched MeSH terms: Silver/pharmacology
  4. Robin Chang YH, Jiang J, Khong HY, Saad I, Chai SS, Mahat MM, et al.
    ACS Appl Mater Interfaces, 2021 Jun 02;13(21):25121-25136.
    PMID: 34008948 DOI: 10.1021/acsami.1c04759
    Transition metal chalcogenides (TMCs) have gained worldwide interest owing to their outstanding renewable energy conversion capability. However, the poor mechanical flexibility of most existing TMCs limits their practical commercial applications. Herein, triggered by the recent and imperative synthesis of highly ductile α-Ag2S, an effective approach based on evolutionary algorithm and ab initio total-energy calculations for determining stable, ductile phases of bulk and two-dimensional Ag
    x
    Se1-x and Ag
    x
    Te1-x compounds was implemented. The calculations correctly reproduced the global minimum bulk stoichiometric P212121-Ag8Se4 and P21/c-Ag8Te4 structures. Recently reported metastable AgTe3 was also revealed but it lacks dynamical stability. Further single-layered screening unveiled two new monolayer P4/nmm-Ag4Se2 and C2-Ag8Te4 phases. Orthorhombic Ag8Se4 crystalline has a narrow, direct band gap of 0.26 eV that increases to 2.68 eV when transforms to tetragonal Ag4Se2 monolayer. Interestingly, metallic P21/c-Ag8Te4 changes to semiconductor when thinned down to monolayer, exhibiting a band gap of 1.60 eV. Present findings confirm their strong stability from mechanical and thermodynamic aspects, with reasonable Vickers hardness, bone-like Young's modulus (E) and high machinability observed in bulk phases. Detailed analysis of the dielectric functions ε(ω), absorption coefficient α(ω), power conversion efficiency (PCE) and refractive index n(ω) of monolayers are reported for the first time. Fine theoretical PCE (SLME method ∼11-28%), relatively high n(0) (1.59-1.93), and sizable α(ω) (104-105 cm-1) that spans the infrared to visible regions indicate their prospects in optoelectronics and photoluminescence applications. Effective strategies to improve the temperature dependent power factor (PF) and figure of merit (ZT) are illustrated, including optimizing the carrier concentration. With decreasing thickness, ZT of p-doped Ag-Se was found to rise from approximately 0.15-0.90 at 300 K, leading to a record high theoretical conversion efficiency of ∼12.0%. The results presented foreshadow their potential application in a hybrid device that combines the photovoltaic and thermoelectric technologies.
    Matched MeSH terms: Silver
  5. Rajendran K, Anwar A, Khan NA, Aslam Z, Raza Shah M, Siddiqui R
    ACS Chem Neurosci, 2020 08 19;11(16):2431-2437.
    PMID: 31347828 DOI: 10.1021/acschemneuro.9b00289
    Naegleria fowleri (N. fowleri) causes primary amoebic meningoencephalitis (PAM) which almost always results in death. N. fowleri is also known as "brain-eating amoeba" due to its literal infestation of the brain leading to an inflammatory response in the brain tissues. Currently, there is no single drug that is available to treat PAM, and most treatments are combinations of antifungal, anticancer, and anti-inflammatory drugs. Recently nanotechnology has gained attention in chemotherapeutic research converging on drug delivery, while oleic acid (OA) has shown positive effects on the human immune system and inflammatory processes. In continuation of our recent research in which we reported the effects of oleic acid conjugated with silver nanoparticles (OA-AgNPs) against free-living amoeba Acanthamoeba castellanii, in this report, we show their antiamoebic effects against N. fowleri. OA alone and its nanoconjugates were tested against the amoeba by using amoebicidal and host cell cytopathogenicity assays. Trypan blue exclusion assay was used to determine cell viability. The results revealed that OA-AgNPs exhibited significantly enhanced antiamoebic effects (P < 0.05) against N. fowleri as compared to OA alone. Evidently, lactate dehydrogenase release shows reduced N. fowleri-mediated host cell cytotoxicity. Based on our study, we anticipate that further studies on OA-AgNPs could potentially provide an alternative treatment of PAM.
    Matched MeSH terms: Silver
  6. Mungroo MR, Shahbaz MS, Anwar A, Saad SM, Khan KM, Khan NA, et al.
    ACS Chem Neurosci, 2020 08 19;11(16):2438-2449.
    PMID: 31961126 DOI: 10.1021/acschemneuro.9b00596
    Naegleria fowleri and Balamuthia mandrillaris are protist pathogens that infect the central nervous system, causing primary amoebic meningoencephalitis and granulomatous amoebic encephalitis with mortality rates of over 95%. Quinazolinones and their derivatives possess a wide spectrum of biological properties, but their antiamoebic effects against brain-eating amoebae have never been tested before. In this study, we synthesized a variety of 34 novel arylquinazolinones derivatives (Q1-Q34) by altering both quinazolinone core and aryl substituents. To study the antiamoebic activity of these synthetic arylquinazolinones, amoebicidal and amoebistatic assays were performed against N. fowleri and B. mandrillaris. Moreover, amoebae-mediated host cells cytotopathogenicity and cytotoxicity assays were performed against human keratinocytes cells in vitro. The results revealed that selected arylquinazolinones derivatives decreased the viability of B. mandrillaris and N. fowleri significantly (P < 0.05) and reduced cytopathogenicity of both parasites. Furthermore, these compounds were also found to be least cytotoxic against HaCat cells. Considering that nanoparticle-based materials possess potent in vitro activity against brain-eating amoebae, we conjugated quinazolinones derivatives with silver nanoparticles and showed that activities of the drugs were enhanced successfully after conjugation. The current study suggests that quinazolinones alone as well as conjugated with silver nanoparticles may serve as potent therapeutics against brain-eating amoebae.
    Matched MeSH terms: Silver
  7. Rajendran K, Anwar A, Khan NA, Siddiqui R
    ACS Chem Neurosci, 2017 12 20;8(12):2626-2630.
    PMID: 29206032 DOI: 10.1021/acschemneuro.7b00430
    The overall aim of this study was to determine whether conjugation with silver nanoparticles enhances effects of available drugs against primary amoebic meningoencephalitis due to Naegleria fowleri. Amphotericin B, Nystatin, and Fluconazole were conjugated with silver nanoparticles, and synthesis was confirmed using UV-visible spectrophotometry. Atomic force microscopy determined their size in range of 20-100 nm. To determine amoebicidal effects, N. fowleri were incubated with drugs-conjugated silver nanoparticles, silver nanoparticles alone, and drugs alone. The findings revealed that silver nanoparticles conjugation significantly enhanced antiamoebic effects of Nystatin and Amphotericin B but not Fluconazole at micromolar concentrations, compared with the drugs alone. For the first time, our findings showed that silver nanoparticle conjugation enhances efficacy of antiamoebic drugs against N. fowleri. Given the rarity of the disease and challenges in developing new drugs, it is hoped that modifying existing drugs to enhance their antiamoebic effects is a useful avenue that holds promise in improving the treatment of brain-eating amoebae infection due to N. fowleri.
    Matched MeSH terms: Silver/administration & dosage*; Silver/chemistry
  8. Tan ST, Ali Umar A, Balouch A, Nafisah S, Yahaya M, Yap CC, et al.
    ACS Comb Sci, 2014 Jul 14;16(7):314-20.
    PMID: 24919039 DOI: 10.1021/co400157m
    This Research Article reports an unusually high efficiency heterogeneous photodegradation of methyl orange (MO) in the presence of Ag nanoparticle-loaded ZnO quasi-nanotube or nanoreactor (A-ZNRs) nanocatalyst grown on FTO substrate. In typical process, photodegradation efficiency of as high as 21.6% per μg per Watts of used catalyst and UV power can be normally obtained within only a 60-min reaction time from this system, which is 10(3) order higher than the reported results. This is equivalent to the turnover frequency of 360 mol mol(-1) h(-1). High-density hexagonal A-ZNRs catalysts were grown directly on FTO substrate via a seed-mediated microwave-assisted hydrolysis growth process utilizing Ag nanoparticle of approximately 3 nm in size as nanoseed and mixture aqueous solution of Zn(NO3)·6H2O, hexamethylenetetramine (HMT), and AgNO3 as the growth solution. A-ZNRs adopts hexagonal cross-section morphology with the inner surface of the reactor characterized by a rough and rugged structure. Transmission electron microscopy imaging shows the Ag nanoparticle grows interstitially in the ZnO nanoreactor structure. The high photocatalytic property of the A-ZNRs is associated with the highly active of inner side's surface of A-ZNRs and the oxidizing effect of Ag nanoparticle. The growth mechanism as well as the mechanism of the enhanced-photocatalytic performance of the A-ZNRs will be discussed.
    Matched MeSH terms: Silver/chemistry*
  9. Anwar A, Mungroo MR, Anwar A, Sullivan WJ, Khan NA, Siddiqui R
    ACS Infect Dis, 2019 Dec 13;5(12):2039-2046.
    PMID: 31612700 DOI: 10.1021/acsinfecdis.9b00263
    Brain-eating amoebae cause devastating infections in the central nervous system of humans, resulting in a mortality rate of 95%. There are limited effective therapeutic options available clinically for treating granulomatous amoebic encephalitis and primary amoebic meningoencephalitis caused by Acanthamoeba castellanii (A. castellanii) and Naegleria fowleri (N. fowleri), respectively. Here, we report for the first time that guanabenz conjugated to gold and silver nanoparticles has significant antiamoebic activity against both A. castellanii and N. fowleri. Gold and silver conjugated guanabenz nanoparticles were synthesized by the one-phase reduction method and were characterized by ultraviolet-visible spectrophotometry and atomic force microscopy. Both metals were facilely stabilized by the coating of guanabenz, which was examined by surface plasmon resonance determination. The average size of gold nanoconjugated guanabenz was found to be 60 nm, whereas silver nanoparticles were produced in a larger size distribution with the average diameter of around 100 nm. Guanabenz and its noble metal nanoconjugates exhibited potent antiamoebic effects in the range of 2.5 to 100 μM against both amoebae. Nanoparticle conjugation enhanced the antiamoebic effects of guanabenz, as more potent activity was observed at a lower effective concentration (2.5 and 5 μM) compared to the drug alone. Moreover, encystation and excystation assays revealed that guanabenz inhibits the interconversion between the trophozoite and cyst forms of A. castellanii. Cysticdal effects against N. fowleri were also observed. Notably, pretreatment of A. castellanii with guanabenz and its nanoconjugates exhibited a significant reduction in the host cell cytopathogenicity from 65% to 38% and 2% in case of gold and silver nanoconjugates, respectively. Moreover, the cytotoxic evaluation of guanabenz and its nanoconjugates revealed negligible cytotoxicity against human cells. Guanabenz is already approved for hypertension and crosses the blood-brain barrier; the results of our current study suggest that guanabenz and its conjugated gold and silver nanoparticles can be repurposed as a potential drug for treating brain-eating amoebic infections.
    Matched MeSH terms: Silver/chemistry*
  10. Mawarnis ER, Ali Umar A, Tomitori M, Balouch A, Nurdin M, Muzakkar MZ, et al.
    ACS Omega, 2018 Sep 30;3(9):11526-11536.
    PMID: 31459253 DOI: 10.1021/acsomega.8b01268
    A combinative effect of two or more individual material properties, such as lattice parameters and chemical properties, has been well-known to generate novel nanomaterials with special crystal growth behavior and physico-chemical performance. This paper reports unusually high catalytic performance of AgPt nanoferns in the hydrogenation reaction of acetone conversion to isopropanol, which is several orders higher compared to the performance shown by pristine Pt nanocatalysts or other metals and metal-metal oxide hybrid catalyst systems. It has been demonstrated that the combinative effect during the bimetallisation of Ag and Pt produced nanostructures with a highly anisotropic morphology, i.e., hierarchical nanofern structures, which provide high-density active sites on the catalyst surface for an efficient catalytic reaction. The extent of the effect of structural growth on the catalytic performance of hierarchical AgPt nanoferns is discussed.
    Matched MeSH terms: Silver
  11. Khan MUA, Abd Razak SI, Mehboob H, Abdul Kadir MR, Anand TJS, Inam F, et al.
    ACS Omega, 2021 Feb 16;6(6):4335-4346.
    PMID: 33623844 DOI: 10.1021/acsomega.0c05596
    In bone tissue engineering, multifunctional composite materials are very challenging. Bone tissue engineering is an innovative technique to develop biocompatible scaffolds with suitable orthopedic applications with enhanced antibacterial and mechanical properties. This research introduces a polymeric nanocomposite scaffold based on arabinoxylan-co-acrylic acid, nano-hydroxyapatite (nHAp), nano-aluminum oxide (nAl2O3), and graphene oxide (GO) by free-radical polymerization for the development of porous scaffolds using the freeze-drying technique. These polymeric nanocomposite scaffolds were coated with silver (Ag) nanoparticles to improve antibacterial activities. Together, nHAp, nAl2O3, and GO enhance the multifunctional properties of materials, which regulate their physicochemical and biomechanical properties. Results revealed that the Ag-coated polymeric nanocomposite scaffolds had excellent antibacterial properties and better microstructural properties. Regulated morphological properties and maximal antibacterial inhibition zones were found in the porous scaffolds with the increasing amount of GO. Moreover, the nanosystem and the polymeric matrix have improved the compressive strength (18.89 MPa) and Young's modulus (198.61 MPa) of scaffolds upon increasing the amount of GO. The biological activities of the scaffolds were investigated against the mouse preosteoblast cell lines (MC3T3-E1) and increasing the quantities of GO helps cell adherence and proliferation. Therefore, our findings showed that these silver-coated polymeric nanocomposite scaffolds have the potential for engineering bone tissue.
    Matched MeSH terms: Silver
  12. Yusof Y, Moosavi S, Johan MR, Badruddin IA, Wahab YA, Hamizi NA, et al.
    ACS Omega, 2021 Feb 16;6(6):4184-4191.
    PMID: 33644542 DOI: 10.1021/acsomega.0c04864
    This study presents the electromagnetic (EM) characterization of a multiwalled carbon nanotubes (MWCNT)-silver nanoparticles (AgNP)-reinforced poly(vinyl alcohol) (PVA) hybrid nanocomposite fabricated via the solution mixing technique. Primarily, the structure and morphological properties of the PVA/MWCNT-AgNP hybrid nanocomposite are confirmed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The complex permittivity (ε*) and permeability (μ*), as well as the electromagnetic scattering parameters are measured using a PNA network analyzer equipped with X-band waveguide. The results showed an enhanced permittivity (ε' ≈ 25) value of the hybrid nanocomposite in the frequency range of 8-12 GHz. However, the permeability decreased to almost zero (μ' ≈ 0.4) since the inclusion of AgNP with an average particle size of 40 nm is not susceptible to magnetization and causes higher magnetic losses (tan δμ) than dielectric losses (tan δε). Remarkably, the hybrid nanocomposite reduced transmission of electromagnetic (EM) wave by nearly 60% in comparison to PVA/MWCNT. This is attributed to the enhanced absorption and reflection at the nanotubes, and metal-dielectric interfaces have induced multiple internal reflections owing to the porous structure of the nanocomposite. The prospect of the PVA/MWCNT-AgNP hybrid nanocomposite is favorable as a thin absorbing material for EM shielding applications.
    Matched MeSH terms: Silver
  13. Wong PM, Juan JC, Lai JC, Lim TH
    ACS Omega, 2020 Jun 16;5(23):13719-13728.
    PMID: 32566837 DOI: 10.1021/acsomega.0c00881
    Sub-10 nm indium metal nanoparticles (In NPs) stabilized on conductive carbon were reacted with silver nitrate in dark conditions in water at room temperature in a galvanic replacement manner to produce an indium hydroxide/silver/carbon nanocomposite (In(OH)3/Ag/C). The chosen carbon imparted colloidal stability, high surface area, and water dispersibility suitable for photodegradation of harmful dyes in water. The size and shape of indium hydroxide and silver nanoparticles produced were found to be 6.6 ± 0.9 nm, similar to that of the In NPs that were started with. The nanocomposite was characterized by transmission electron microscopy, energy dispersive X-ray spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. The galvanic reaction between In NPs and silver nitrate was tracked with UV-vis spectroscopy in a control experiment without a carbon substrate to confirm that the reaction was indeed thermodynamically spontaneous as indicated by the positive electromotive force (EMF) of +1.14 V calculated for In/Ag+ redox couple. The photocatalytic performance of the nanocomposite was evaluated to be approximately 90% under UVC radiation when 10 ppm of methylene blue and 13 wt % of indium hydroxide/silver loading on carbon were used.
    Matched MeSH terms: Silver; Silver Nitrate
  14. Barber TJ, Crabtree B, Cortes CP, Guaraldi G, Hoy JF, Rajasuriar R, et al.
    AIDS Care, 2023 Aug;35(8):1149-1153.
    PMID: 36994591 DOI: 10.1080/09540121.2023.2190956
    ABSTRACTGlobally the community of people with HIV is ageing, and some of these have increasingly complex care needs, with a known excess of non-HIV related comorbidities and related issues including consequent polypharmacy. At the 2022 International AIDS Conference in Montréal, Canada, the "Silver Zone" was created in the Global Village as a safe space for older people with HIV. As part of the Silver Zone activities, a session discussing global models of care for in this group was held. HIV treatment providers and advocates from diverse resource settings and with a diversity of expertise were invited to share their experience, reflections, and ideas, and this consensus statement was formed based on these discussions. Different approaches to care emerged, based on local needs and resources, and it became clear that issues of complexity and frailty need not be age limited. Despite clear regional differences, some common themes became apparent, and a consensus was established on basic principles that may be considered in diverse settings. These are discussed here, with agreement on necessary proximal steps to develop bespoke person-centred care models.
    Matched MeSH terms: Silver
  15. Anwar A, Ting ELS, Anwar A, Ain NU, Faizi S, Shah MR, et al.
    AMB Express, 2020 Feb 03;10(1):24.
    PMID: 32016777 DOI: 10.1186/s13568-020-0960-9
    Acanthamoeba spp. are the causative agent of Acanthamoeba keratitis and granulomatous amoebic encephalitis (GAE). The current options to treat Acanthamoeba infections have limited success. Silver nanoparticles show antimicrobial effects and enhance the efficacy of their payload at the specific biological targets. Natural folk plants have been widely used for treating diseases as the phytochemicals from several plants have been shown to exhibit amoebicidal effects. Herein, we used natural products of plant or commercial sources including quercetin (QT), kolavenic acid (PGEA) isolated from plant extracts of Polyalthia longifolia var pendula and crude plant methanolic extract of Caesalpinia pulcherrima (CPFLM) as antiacanthamoebic agents. Furthermore, these plant-based materials were conjugated with silver nanoparticles (AgNPs) to determine the effects of the natural compounds and their nanoconjugates against a clinical isolate of A. castellanii from a keratitis patient (ATCC 50492) belonging to the T4 genotype. The compounds were conjugated with AgNPs and characterized by using ultraviolet visible spectrophotometry and atomic force microscopy. Quercetin coated silver nanoparticles (QT-AgNPs) showed characteristic surface plasmon resonance band at 443 nm and the average size distribution was found to be around 45 nm. The natural compounds alone and their nanoconjugates were tested for the viability of amoebae, encystation and excystation activity against A. castellanii. The natural compounds showed significant growth inhibition of A. castellanii while QT-AgNPs specifically exhibited enhanced antiamoebic effects as well as interrupted the encystation and excystation activity of the amoebae. Interestingly, these compounds and nanoconjugates did not exhibit in vitro cytotoxic effects against human cells. Plant-based compounds and extracts could be an interesting strategy in development of alternative therapeutics against Acanthamoeba infections.
    Matched MeSH terms: Silver
  16. Kassim, S., Tahrin, R.A.A., Rusdi, N.F., Harun, N.A.
    ASM Science Journal, 2018;11(101):86-95.
    MyJurnal
    A feasible production of poly (methyl methacrylate)@alloy (gold-silver) core shell has
    been presented as candidate in enhanced detection of surface enhanced Raman scattering
    (SERS). Free emulsifier- emulsion synthesised PMMA sphere with average size of 419 nm in
    diameter were used as core material for incorporation of alloy nanoparticles (6 nm) resulting
    a core-shell structure. The fabrication of PMMA@alloy SERS substrate was successfully
    done via self-assembly thus the produced SERS substrate that comprise of unique optical
    properties combination arising from periodic core arrangement and plasmonic activity of
    alloy nanoparticles. Alloy is bimetallic nanoparticles in which the combination of silver
    (Ag) and gold (Au) present an absolutely improved light resistance as compared to single
    metal alone with great surface plasmon resonance. Morphology and elemental analysis was
    performed through scanning electron microscope (SEM) and the analysis showing species of
    both Au and Ag in single alloy nanoparticles. The alloy nanoparticles were also observed to
    homogenously coating the PMMA sphere. Surface plasmon resonance activity was maximum
    at 476 nm obtained from UV-Visible spectroscopy. High surface production was observed
    to have periodically arranged PMMA@alloy core -shell and potentially to be used as SERS
    substrate.
    Matched MeSH terms: Silver
  17. Usman A, Fun HK, Chantrapromma S, Zhu HL, Wang XJ
    Acta Crystallogr C, 2003 Mar;59(Pt 3):m97-9.
    PMID: 12711770
    In the ternary title compound, catena-poly[[silver(I)-mu-ethylenediamine-kappa(2)N:N'] 3-nitrobenzoate monohydrate], [[Ag(C(2)H(8)N(2))](C(7)H(4)NO(4)) x H(2)O](n), the Ag atom is bicoordinated in a linear configuration by two different N atoms from two symmetry-related ethylenediamine ligands, thus giving linear polymeric chains with an [-Ag-N-C-C-N-](n) backbone running parallel to the a axis. In the crystal packing, these linear chains are interconnected by N-H...O and O-H...O hydrogen bonds to form layers parallel to the ab plane.
    Matched MeSH terms: Silver
  18. Ahmad J, Abdul Halim SN, How FN
    Acta Crystallogr E Crystallogr Commun, 2015 Jun 1;71(Pt 6):o410-1.
    PMID: 26090195 DOI: 10.1107/S2056989015009159
    The title compound, Ph3(PhCH2)P(+)·Cl(-)·H2O, was obtained unintentionally as the product of an attempted synthesis of a silver di-thio-carbamate complex using benzyl-tri-phenyl-phospho-nium as the counter-ion. The asymmetric unit consists of a phospho-nium cation and a chloride anion, and a water mol-ecule of crystallization. In the crystal, the chloride ion is linked to the water mol-ecule by an O-H⋯Cl hydrogen bond. The three units are further linked via C-H⋯Cl and C-H⋯O hydrogen bonds and C-H⋯ π inter-actions, forming a three-dimensional structure.
    Matched MeSH terms: Silver
  19. Haarindraprasad R, Hashim U, Gopinath SC, Perumal V, Liu WW, Balakrishnan SR
    Anal Chim Acta, 2016 Jun 21;925:70-81.
    PMID: 27188319 DOI: 10.1016/j.aca.2016.04.030
    Diabetes is a metabolic disease with a prolonged elevated level of glucose in the blood leads to long-term complications and increases the chances for cardiovascular diseases. The present study describes the fabrication of a ZnO nanowire (NW)-modified interdigitated electrode (IDE) to monitor the level of blood glucose. A silver IDE was generated by wet etching-assisted conventional lithography, with a gap between adjacent electrodes of 98.80 μm. The ZnO-based thin films and NWs were amended by sol-gel and hydrothermal routes. High-quality crystalline and c-axis orientated ZnO thin films were observed by XRD analyses. The ZnO thin film was annealed for 1, 3 and 5 h, yielding a good-quality crystallite with sizes of 50, 100 and 110 nm, and the band gaps were measured as 3.26, 3.20 and 3.17 eV, respectively. Furthermore, a flower-modeled NW was obtained with the lowest diameter of 21 nm. Our designed ZnO NW-modified IDE was shown to have a detection limit as low as 0.03 mg/dL (correlation coefficient = 0.98952) of glucose with a low response time of 3 s, perform better than commercial glucose meter, suitable to instantly monitor the glucose level of diabetes patients. This study demonstrated the high performance of NW-mediated IDEs for glucose sensing as alternative to current glucose sensors.
    Matched MeSH terms: Silver
  20. Mahmoudian MR, Basirun WJ, Woi PM, Yousefi R, Alias Y
    Anal Bioanal Chem, 2019 Jan;411(2):517-526.
    PMID: 30498983 DOI: 10.1007/s00216-018-1476-x
    We report a green synthesis of oatmeal ZnO/silver composites in the presence of L-glutamine as an electrochemical sensor for Pb2+ detection. The synthesis was performed via the direct reduction of Ag+ in the presence of L-glutamine in NaOH. X-ray diffraction indicated that the Ag+ was completely reduced to metallic Ag. The field emission scanning electron microscopy (FESEM) and energy dispersive X-ray results confirmed an oatmeal-like morphology of the ZnO with the presence of Ag. The FESEM images showed the effect of L-glutamine on the ZnO morphology. The EIS results confirmed a significant decrease in the charge transfer resistance of the modified glassy carbon electrode due to the presence of Ag. From the differential pulse voltammetry results, a linear working range for the concentration of Pb2+ between 5 and 6 nM with LOD of 0.078 nM (S/N = 3) was obtained. The sensitivity of the linear segment is 1.42 μA nM-1 cm-2. The presence of L-glutamine as the capping agent and stabilizer decreases the size of Ag nanoparticles and prevents the agglomeration of ZnO, respectively. Graphical abstract ᅟ.
    Matched MeSH terms: Silver
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