Displaying publications 361 - 380 of 403 in total

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  1. Rashidi Nodeh H, Wan Ibrahim WA, Kamboh MA, Sanagi MM
    Chemosphere, 2017 Jan;166:21-30.
    PMID: 27681257 DOI: 10.1016/j.chemosphere.2016.09.054
    A new graphene-based tetraethoxysilane-methyltrimethoxysilane sol-gel hybrid magnetic nanocomposite (Fe3O4@G-TEOS-MTMOS) was synthesised, characterized and successfully applied in magnetic solid-phase extraction (MSPE) for simultaneous analysis of polar and non-polar organophosphorus pesticides from several water samples. The Fe3O4@G-TEOS-MTMOS nanocomposite was characterized using Fourier transform-infrared spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy and X-ray diffraction. Separation, determination and quantification were achieved using gas chromatography coupled with micro electron capture detector. Adsorption capacity of the sorbent was calculated using Langmuir equation. MSPE was linear in the range 100-1000 pg mL(-1) for phosphamidon and dimethoate, and 10-100 pg mL(-1) for chlorpyrifos and diazinon, with limit of detection (S/N = 3) of 19.8, 23.7, 1.4 and 2.9 pg mL(-1) for phosphamidon, dimethoate, diazinon and chlorpyrifos, respectively. The LODs obtained is well below the maximum residual level (100 pg mL(-1)) as set by European Union for pesticides in drinking water. Acceptable precision (%RSD) was achieved for intra-day (1.3-8.7%, n = 3) and inter-day (7.6-17.8%, n = 15) analyses. Fe3O4@G-TEOS-MTMOS showed high adsorption capacity (54.4-76.3 mg g(-1)) for the selected OPPs. No pesticide residues were detected in the water samples analysed. Excellent extraction recoveries (83-105%) were obtained for the spiked OPPs from tap, river, lake and sea water samples. The newly synthesised Fe3O4@G-TEOS-MTMOS showed high potential as adsorbent for OPPs analysis.
    Matched MeSH terms: Oxides/chemistry
  2. Abd Muain MF, Cheo KH, Omar MN, Amir Hamzah AS, Lim HN, Salleh AB, et al.
    Bioelectrochemistry, 2018 Aug;122:199-205.
    PMID: 29660648 DOI: 10.1016/j.bioelechem.2018.04.004
    Hepatitis B virus core antigen (HBcAg) is the major structural protein of hepatitis B virus (HBV). The presence of anti-HBcAg antibody in a blood serum indicates that a person has been exposed to HBV. This study demonstrated that the immobilization of HBcAg onto the gold nanoparticles-decorated reduced graphene oxide (rGO-en-AuNPs) nanocomposite could be used as an antigen-functionalized surface to sense the presence of anti-HBcAg. The modified rGO-en-AuNPs/HBcAg was then allowed to undergo impedimetric detection of anti-HBcAg with anti-estradiol antibody and bovine serum albumin as the interferences. Upon successful detection of anti-HBcAg in spiked buffer samples, impedimetric detection of the antibody was then further carried out in spiked human serum samples. The electrochemical response showed a linear relationship between electron transfer resistance and the concentration of anti-HBcAg ranging from 3.91ngmL-1 to 125.00ngmL-1 with lowest limit of detection (LOD) of 3.80ngmL-1 at 3σm-1. This established method exhibits potential as a fast and convenient way to detect anti-HBcAg.
    Matched MeSH terms: Oxides/chemistry
  3. Siriviriyanun A, Tsai YJ, Voon SH, Kiew SF, Imae T, Kiew LV, et al.
    Mater Sci Eng C Mater Biol Appl, 2018 Aug 01;89:307-315.
    PMID: 29752102 DOI: 10.1016/j.msec.2018.04.020
    In this study, nanohybrid materials consisting of graphene oxide (GO), β‑cyclodextrin (CD) and poly(amido amine) dendrimer (DEN) were successfully prepared by covalent bonding. GO-CD and GO-CD-DEN were found to be potential nanocarriers for anticancer drugs including chemotherapeutics (doxorubicin (DOX), camptothecin (CPT)) and photosensitizer (protoporphyrin IX (PpIX)). GO-CD possessed 1.2 times higher DOX-loading capacity than GO due to inclusion of additional DOX to the CD. The drug loading on GO-CD-DEN increased in the order: DOX 
    Matched MeSH terms: Oxides/chemistry
  4. Pedersen M, Stafoggia M, Weinmayr G, Andersen ZJ, Galassi C, Sommar J, et al.
    Eur Urol Focus, 2018 01;4(1):113-120.
    PMID: 28753823 DOI: 10.1016/j.euf.2016.11.008
    BACKGROUND: Ambient air pollution contains low concentrations of carcinogens implicated in the etiology of urinary bladder cancer (BC). Little is known about whether exposure to air pollution influences BC in the general population.

    OBJECTIVE: To evaluate the association between long-term exposure to ambient air pollution and BC incidence.

    DESIGN, SETTING, AND PARTICIPANTS: We obtained data from 15 population-based cohorts enrolled between 1985 and 2005 in eight European countries (N=303431; mean follow-up 14.1 yr). We estimated exposure to nitrogen oxides (NO2 and NOx), particulate matter (PM) with diameter <10μm (PM10), <2.5μm (PM2.5), between 2.5 and 10μm (PM2.5-10), PM2.5absorbance (soot), elemental constituents of PM, organic carbon, and traffic density at baseline home addresses using standardized land-use regression models from the European Study of Cohorts for Air Pollution Effects project.

    OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We used Cox proportional-hazards models with adjustment for potential confounders for cohort-specific analyses and meta-analyses to estimate summary hazard ratios (HRs) for BC incidence.

    RESULTS AND LIMITATIONS: During follow-up, 943 incident BC cases were diagnosed. In the meta-analysis, none of the exposures were associated with BC risk. The summary HRs associated with a 10-μg/m3 increase in NO2 and 5-μg/m3 increase in PM2.5 were 0.98 (95% confidence interval [CI] 0.89-1.08) and 0.86 (95% CI 0.63-1.18), respectively. Limitations include the lack of information about lifetime exposure.

    CONCLUSIONS: There was no evidence of an association between exposure to outdoor air pollution levels at place of residence and risk of BC.

    PATIENT SUMMARY: We assessed the link between outdoor air pollution at place of residence and bladder cancer using the largest study population to date and extensive assessment of exposure and comprehensive data on personal risk factors such as smoking. We found no association between the levels of outdoor air pollution at place of residence and bladder cancer risk.

    Matched MeSH terms: Nitrogen Oxides/adverse effects
  5. Barahuie F, Saifullah B, Dorniani D, Fakurazi S, Karthivashan G, Hussein MZ, et al.
    Mater Sci Eng C Mater Biol Appl, 2017 May 01;74:177-185.
    PMID: 28254283 DOI: 10.1016/j.msec.2016.11.114
    We have synthesized graphene oxide using improved Hummer's method in order to explore the potential use of the resulting graphene oxide as a nanocarrier for an active anticancer agent, chlorogenic acid (CA). The synthesized graphene oxide and chlorogenic acid-graphene oxide nanocomposite (CAGO) were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential thermogravimetry analysis, Raman spectroscopy, powder X-ray diffraction (PXRD), UV-vis spectroscopy and high resolution transmission electron microscopy (HRTEM) techniques. The successful conjugation of chlorogenic acid onto graphene oxide through hydrogen bonding and π-π interaction was confirmed by Raman spectroscopy, FTIR analysis and X-ray diffraction patterns. The loading of CA in the nanohybrid was estimated to be around 13.1% by UV-vis spectroscopy. The release profiles showed favourable, sustained and pH-dependent release of CA from CAGO nanocomposite and conformed well to the pseudo-second order kinetic model. Furthermore, the designed anticancer nanohybrid was thermally more stable than its counterpart. The in vitro cytotoxicity results revealed insignificant toxicity effect towards normal cell line, with a viability of >80% even at higher concentration of 50μg/mL. Contrarily, CAGO nanocomposite revealed enhanced toxic effect towards evaluated cancer cell lines (HepG2 human liver hepatocellular carcinoma cell line, A549 human lung adenocarcinoma epithelial cell line, and HeLa human cervical cancer cell line) compared to its free form.
    Matched MeSH terms: Oxides/chemistry
  6. Saifullah B, Chrzastek A, Maitra A, Naeemullah B, Fakurazi S, Bhakta S, et al.
    Molecules, 2017 Oct 12;22(10).
    PMID: 29023399 DOI: 10.3390/molecules22101560
    Tuberculosis (TB) is a bacterial disease responsible for millions of infections and preventable deaths each year. Its treatment is complicated by patients' noncompliance due to dosing frequency, lengthy treatment, and adverse side effects associated with current chemotherapy. However, no modifications to the half-a-century old standard chemotherapy have been made based on a nanoformulation strategy to improve pharmacokinetic efficacy. In this study, we have designed a new nanodelivery formulation, using graphene oxide as the nanocarrier, loaded with the anti-TB antibiotic, ethambutol. The designed formulation was characterized using a number of molecular analytical techniques. It was found that sustained release of the drug resulted in better bioavailability. In addition, the designed formulation demonstrated high biocompatibility with mouse fibroblast cells. The anti-TB activity of the nanodelivery formulation was determined using whole-cell resazurin microtiter plate assay, modified-spot culture growth inhibition assay, and biofilm inhibition assay. The nanodelivery formulation showed good anti-mycobacterial activity. The anti-mycobacterial activity of Ethambutol was unaffected by the drug loading and release process. The results of this study demonstrated the potential of this new nanodelivery formulation strategy to be considered for modifying existing chemotherapy to yield more efficacious antibiotic treatment against TB.
    Matched MeSH terms: Oxides/chemistry*
  7. Usman MS, Hussein MZ, Kura AU, Fakurazi S, Masarudin MJ, Ahmad Saad FF
    Molecules, 2018 Feb 24;23(2).
    PMID: 29495251 DOI: 10.3390/molecules23020500
    We have synthesized a graphene oxide (GO)-based theranostic nanodelivery system (GOTS) for magnetic resonance imaging (MRI) using naturally occurring protocatechuic acid (PA) as an anticancer agent and gadolinium (III) nitrate hexahydrate (Gd) as the starting material for a contrast agent,. Gold nanoparticles (AuNPs) were subsequently used as second diagnostic agent. The GO nanosheets were first prepared from graphite via the improved Hummer's protocol. The conjugation of the GO and the PA was done via hydrogen bonding and π-π stacking interactions, followed by surface adsorption of the AuNPs through electrostatic interactions. GAGPA is the name given to the nanocomposite obtained from Gd and PA conjugation. However, after coating with AuNPs, the name was modified to GAGPAu. The physicochemical properties of the GAGPA and GAGPAu nanohybrids were studied using various characterization techniques. The results from the analyses confirmed the formation of the GOTS. The powder X-ray diffraction (PXRD) results showed the diffractive patterns for pure GO nanolayers, which changed after subsequent conjugation of the Gd and PA. The AuNPs patterns were also recorded after surface adsorption. Cytotoxicity and magnetic resonance imaging (MRI) contrast tests were also carried out on the developed GOTS. The GAGPAu was significantly cytotoxic to the human liver hepatocellular carcinoma cell line (HepG2) but nontoxic to the standard fibroblast cell line (3T3). The GAGPAu also appeared to possess higher T1 contrast compared to the pure Gd and water reference. The GOTS has good prospects of serving as future theranostic platform for cancer chemotherapy and diagnosis.
    Matched MeSH terms: Oxides/chemistry*
  8. Usman MS, Hussein MZ, Fakurazi S, Masarudin MJ, Ahmad Saad FF
    PLoS One, 2018;13(7):e0200760.
    PMID: 30044841 DOI: 10.1371/journal.pone.0200760
    We have synthesized a bimodal theranostic nanodelivery system (BIT) that is based on graphene oxide (GO) and composed of a natural chemotherapeutic agent, chlorogenic acid (CA) used as the anticancer agent, while gadolinium (Gd) and gold nanoparticles (AuNPs) were used as contrast agents for magnetic resonance imaging (MRI) modality. The CA and Gd guest agents were simultaneously loaded on the GO nanolayers using chemical interactions, such as hydrogen bonding and π-π non-covalent interactions to form GOGCA nanocomposite. Subsequently, the AuNPs were doped on the surface of the GOGCA by means of electrostatic interactions, which resulted in the BIT. The physico-chemical studies of the BIT affirmed its successful development. The X-ray diffractograms (XRD) collected of the various stages of BIT synthesis showed the successive development of the hybrid system, while 90% of the chlorogenic acid was released in phosphate buffer solution (PBS) at pH 4.8. This was further reaffirmed by the in vitro evaluations, which showed stunted HepG2 cancer cells growth against the above 90% cell growth in the control cells. A reverse case was recorded for the 3T3 normal cells. Further, the acquired T1-weighted image of the BIT doped samples obtained from the MRI indicated contrast enhancement in comparison with the plain Gd and water references. The abovementioned results portray our BIT as a promising future chemotherapeutic for anticancer treatment with diagnostic modalities.
    Matched MeSH terms: Oxides/chemistry
  9. Saifullah B, Maitra A, Chrzastek A, Naeemullah B, Fakurazi S, Bhakta S, et al.
    Molecules, 2017 Oct 12;22(10).
    PMID: 29023384 DOI: 10.3390/molecules22101697
    Tuberculosis (TB) is a dreadful bacterial disease, infecting millions of human and cattle every year worldwide. More than 50 years after its discovery, ethambutol continues to be an effective part of the World Health Organization's recommended frontline chemotherapy against TB. However, the lengthy treatment regimens consisting of a cocktail of antibiotics affect patient compliance. There is an urgent need to improve the current therapy so as to reduce treatment duration and dosing frequency. In this study, we have designed a novel anti-TB multifunctional formulation by fabricating graphene oxide with iron oxide magnetite nanoparticles serving as a nano-carrier on to which ethambutol was successfully loaded. The designed nanoformulation was characterised using various analytical techniques. The release of ethambutol from anti-TB multifunctional nanoparticles formulation was found to be sustained over a significantly longer period of time in phosphate buffer saline solution at two physiological pH (7.4 and 4.8). Furthermore, the nano-formulation showed potent anti-tubercular activity while remaining non-toxic to the eukaryotic cells tested. The results of this in vitro evaluation of the newly designed nano-formulation endorse its further development in vivo.
    Matched MeSH terms: Oxides/chemistry*
  10. Lau LC, Lee KT, Mohamed AR
    J Hazard Mater, 2010 Nov 15;183(1-3):738-45.
    PMID: 20724075 DOI: 10.1016/j.jhazmat.2010.07.088
    In order to reduce the negative impact of coal utilization for energy generation, the pollutants present in the flue gas of coal combustion such as sulfur dioxide (SO(2)) and nitrogen oxide (NO) must be effectively removed before releasing to the atmosphere. Thus in this study, sorbent prepared from rice husk ash that is impregnated with copper is tested for simultaneous removal of SO(2) and NO from simulated flue gas. The effect of various sorbent preparation parameters; copper loading, RHA/CaO ratio, hydration period and NaOH concentration on the sorbent desulfurization/denitrification capacity was studied using Design-Expert Version 6.0.6 software. Specifically, Central Composite Design (CCD) coupled with Response Surface Method (RSM) was used. Significant individual parameters that affect the sorbent capacity are copper loading and NaOH concentration. Apart from that, interaction between the following parameters was also found to have significant effect; copper loading, RHA/CaO ratio and NaOH concentration. The optimum sorbent preparation condition for this study was found to be 3.06% CuO loading, RHA/CaO ratio of 1.41, 8.05 h of hydration period and NaOH concentration of 0.80 M. Sorbent characterization using SEM, XRD and surface area analysis were used to describe the effect of sorbent preparation parameters on the desulfurization/denitrification activity.
    Matched MeSH terms: Oxides
  11. Mousavi Z, Soofivand F, Esmaeili-Zare M, Salavati-Niasari M, Bagheri S
    Sci Rep, 2016 Feb 01;6:20071.
    PMID: 26832329 DOI: 10.1038/srep20071
    In this work, zinc chromite (ZnCr2O4) nanostructures have been synthesized through co-precipitation method. The effect of various parameters such as alkaline agent, pH value, and capping agent type was investigated on purity, particle size and morphology of samples. It was found that particle size and morphology of the products could be greatly influenced via these parameters. The synthesized products were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), fourier transform infrared (FT-IR) spectra, X-ray energy dispersive spectroscopy (EDS), photoluminescence (PL) spectroscopy, diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometry (VSM). The superhydrophilicity of the calcined oxides was investigated by wetting experiments and a sessile drop technique which carried out at room temperature in air to determine the surface and interfacial interactions. Furthermore, the photocatalytic activity of ZnCr2O4 nanoparticles was confirmed by degradation of anionic dyes such as Eosin-Y and phenol red under UV light irradiation. The obtained ZnCr2O4 nanoparticles exhibit a paramagnetic behavior although bulk ZnCr2O4 is antiferromagnetic, this change in magnetic property can be ascribed to finite size effects.
    Matched MeSH terms: Oxides
  12. Tang SN, Fakhru'l-Razi A, Hassan MA, Karim MI
    PMID: 10595441
    Rubber latex effluent is a polluting source that has a high biochemical oxygen demand (BOD). It is estimated that about 100 million liters of effluent are discharged daily from rubber processing factories. Utilization of this effluent such as the use of a coupled system not only can reduce the cost of treatment but also yield a fermentation feedstock for the production of bioplastic. This study initially was carried out to increase the production of organic acids by anaerobic treatment of rubber latex effluent. It was found that through anaerobic treatment the concentration of organic acids did not increase. Consequently, separation of organic acids from rubber latex effluent by anion exchange resin was examined as a preliminary study of recovering acetic and propionic acids. However, the suspended solids (SS) content in the raw effluent was rather high which partially blocked the ion-exchange columns. Lime was used to remove the SS in the rubber latex effluent. After the lime precipitation process, organic acids were found to adsorb strongly onto the anion exchange resin. Less adsorption of organic acids onto the resin was observed before the lime precipitation. This was probably due to more sites being occupied by colloidal particles on the resin thus inhibiting the adsorption of organic acids. The initial concentration of organic acids in the raw effluent was 3.9 g/L. After ion exchange, the concentration of the organic acids increased to 27 g/L, which could be utilized for production of polyhydroxyalkanoates (PHA). For PHA accumulation stage, concentrated rubber latex effluent obtained from ion exchange resins and synthetic acetic acid were used as the carbon source. Quantitative analyses from fed batch culture via HPLC showed that the accumulation of PHA in Alcaligenes eutrophus was maximum with a concentration of 1.182 g/L when cultivated on synthetic acetic acid, corresponding to a yield of 87% based on its cell dry weight. The dry cell weight increased from 0.71 to 1.67 g/L. On the other hand, using concentrated rubber latex effluent containing acetic and propionic acids resulted in reduced PHA content by dry weight (14%) but the dry cell weight increased from 0.49 to 1.30 g/L. The results clearly indicated that the cells grow well in rubber latex effluent but no PHA was accumulated. This could be due to the high concentration of propionic acid in culture broth or other factors such as heavy metals. Thus further work is required before rubber latex effluent can be utilized as a substrate for PHA production industrially.
    Matched MeSH terms: Oxides
  13. Nurfarhana Rosman, Nur Syazwani Abdul Malek, Mohamad Rusop Mahmood, Zuraida Khusaimi, Noor Asnida Asli
    Science Letters, 2020;14(2):47-57.
    MyJurnal
    Effect of different storage temperatures on physical and physiological changes of Golden Lily mango was investigated. Zinc oxide (ZnO) nanoparticles edible coating was prepared by sol-gel method and Golden Lily mangoes were dipped in the solution and stored at different (32℃, 27℃ and 5℃) temperatures for 7 days. The mangoes were characterized by Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), Fourier-transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) after 7 days of storage. Both the analysis of FESEM and EDX revealed the highest volume ratio of ZnO nanoparticles with a homogeneous dispersion throughout the mango peel surface is at 5℃. FTIR spectra revealed the absence of Zn–O bonding as metal oxides absorption is expected to be in the region below 700 cm-1. The mangoes stored at 5℃ delayed ripening, slowed down weight loss and found to be firmer than mangoes stored at 32℃ and 27℃.
    Matched MeSH terms: Oxides
  14. Ahmad H, Haseen U, Umar K, Ansari MS, Ibrahim MNM
    Mikrochim Acta, 2019 08 27;186(9):649.
    PMID: 31456042 DOI: 10.1007/s00604-019-3753-6
    The authors describe a method for solvent-free mechano-chemical synthesis of a bioinspired sorbent. A 2D ultra-thin carbon sheet similar to graphene oxide was prepared using a natural waste (onion sheet). The formation of 2D carbon sheets was confirmed by Raman spectroscopy, X-ray photoelectron spectroscopy and ATR-IR. The surface morphology was characterized by field emission scanning electron microscopy and high-resolution tunneling electron microscopy. The carbon sheets were decorated with crystalline MnFe2O4 nanoparticles by solid-state reaction at room temperature. The presence of magnetic particles in the final product was confirmed by vibrating sample magnetometry and electron microscopy. The synergistic effect of carbon sheets and MnFe2O4 led to an enhanced sorption of arsenic species compared to bare carbon sheets or to MnFe2O4 nanoparticles. A column was prepared for the simultaneous preconcentration and determination of trace levels of As(III) and As(V) from water samples. The preconcentration factors are between 900 and 833 for As(III) and As(V) species, respectively. The linearity of the calibration plot ranges from 0.4-10 ng mL-1. The detection limits (at 3σ) for both As(III) and As(V) are 30 pg mL-1. The Student's t values for the analysis of spiked samples are lower than the critical Student's t values at a 95% confidence level. The recoveries from spiked water samples range between 99 and 102.8%. Graphical abstract Schematic representation of the preparation of carbon sheets similar to graphene oxide from onion sheaths after pyrolysis at 800 °C. The prepared carbon sheet-MnFe2O4 composite shows excellent arsenic sorption and preconcentration down to the pg mL-1 concentration.
    Matched MeSH terms: Oxides
  15. Nurul Najwa Abd Malek, Rusdin Laiman
    Science Letters, 2018;12(1):63-76.
    MyJurnal
    The aim of this study was to investigate the potential of treated rice husk ash (RHA) as adsorbent to adsorb acidic SO2 gas. The treated RHA was prepared using a water hydration method by mixing the RHA, Calcium oxide (CaO) and Sodium Hydroxide (NaOH). The addition of NaOH is to increase the dissolution of silica from the RHA to form reactive species responsible for higher desulfurization activity. The untreated and treated RHA were subjected to several characterizations and the characteristics of the adsorbents were compared. The functional groups present on the surface of the adsorbent were determined using Fourier Transform Infrared (FTIR). The chemical composition of the untreated and treated RHA was analyzed by using X-ray Fluorescence (XRF). Scanning electron microscope (SEM) analysis showed that the treated RHA has higher porosity compared to untreated RHA. Based on the SO2 adsorption analysis, it was found that the treated RHA has higher adsorption capacity, 62.22 mg/g, compared to untreated RHA, 1.49 mg/g.
    Matched MeSH terms: Oxides
  16. Mallikarjuna K, Nasif O, Ali Alharbi S, Chinni SV, Reddy LV, Reddy MRV, et al.
    Biomolecules, 2021 01 29;11(2).
    PMID: 33572968 DOI: 10.3390/biom11020190
    Continuously increasing energy demand and growing concern about energy resources has attracted much research in the field of clean and sustainable energy sources. In this context, zero-emission fuels are required for energy production to reduce the usage of fossil fuel resources. Here, we present the synthesis of Pd-Ag-decorated reduced graphene oxide (rGO) nanostructures using a green chemical approach with stevia extract for hydrogen production and antibacterial studies under light irradiation. Moreover, bimetallic nanostructures are potentially lime lighted due to their synergetic effect in both scientific and technical aspects. Structural characteristics such as crystal structure and morphological features of the synthesized nanostructures were analyzed using X-ray diffraction and transmission electron microscopy. Analysis of elemental composition and oxidation states was carried out by X-ray photoelectron spectroscopy. Optical characteristics of the biosynthesized nanostructures were obtained by UV-Vis absorption spectroscopy, and Fourier transform infrared spectroscopy was used to investigate possible functional groups that act as reducing and capping agents. The antimicrobial activity of the biosynthesized Pd-Ag-decorated rGO nanostructures was excellent, inactivating 96% of Escherichia coli cells during experiments over 150 min under visible light irradiation. Hence, these biosynthesized Pd-Ag-decorated rGO nanostructures can be utilized for alternative nanomaterial-based drug development in the future.
    Matched MeSH terms: Oxides
  17. Promsuwan K, Soleh A, Saisahas K, Saichanapan J, Kanatharana P, Thavarungkul P, et al.
    J Colloid Interface Sci, 2021 Sep;597:314-324.
    PMID: 33872888 DOI: 10.1016/j.jcis.2021.03.162
    A unique nanocomposite was fabricated using negatively charged manganese dioxide nanoparticles, poly (3,4-ethylenedioxythiophene) and reduced graphene oxide (MnO2/PEDOT/rGO). The nanocomposite was deposited on a glassy carbon electrode (GCE) functionalized with amino groups. The modified GCE was used to electrochemically detect dopamine (DA). The surface morphology, charge effect and electrochemical behaviours of the modified GCE were characterized by scanning electron microscopy, energy dispersive X-ray analysis (EDX), cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The MnO2/PEDOT/rGO/GCE exhibited excellent performance towards DA sensing with a linear range between 0.05 and 135 µM with a lowest detection limit of 30 nM (S/N = 3). Selectivity towards DA was high in the presence of high concentrations of the typical interferences ascorbic acid and uric acid. The stability and reproducibility of the electrode were good. The sensor accurately determined DA in human serum. The synergic effect of the multiple components of the fabricated nanocomposite were critical to the good DA sensing performance. rGO provided a conductive backbone, PEDOT directed the uniform growth of MnO2 and adsorbed DA via pi-pi and electrostatic interaction, while the negatively charged MnO2 provided adsorption and catalytic sites for protonated DA. This work produced a promising biosensor that sensitively and selectively detected DA.
    Matched MeSH terms: Oxides
  18. Masri A, Abdelnasir S, Anwar A, Iqbal J, Numan A, Jagadish P, et al.
    Appl Microbiol Biotechnol, 2021 Apr;105(8):3315-3325.
    PMID: 33797573 DOI: 10.1007/s00253-021-11221-1
    BACKGROUND: Conducting polymer based nanocomposites are known to be effective against pathogens. Herein, we report the antimicrobial properties of multifunctional polypyrrole-cobalt oxide-silver nanocomposite (PPy-Co3O4-AgNPs) for the first time. Antibacterial activities were tested against multi-drug-resistant Gram-negative Escherichia coli (E. coli) and Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) bacteria, while antiamoebic effects were assessed against opportunistic protist Acanthamoeba castellanii (A. castellanii).

    RESULTS: The ternary nanocomposite containing conducting polymer polypyrrole, cobalt oxide, and silver nanoparticles showed potent antimicrobial effects against these pathogens. The antibacterial assay showed that PPy-Co3O4-AgNPs exhibited significant bactericidal activity against neuropathogenic E. coli K1 at only 8 μg/mL as compared to individual components of the nanocomposite, whereas a 70 % inhibition of A. castellanii viability was observed at 50 μg/mL. Moreover, PPy-Co3O4-AgNPs were found to have minimal cytotoxicity against human keratinocytes HaCaT cells in vitro even at higher concentration (50 μg/mL), and also reduced the microbes-mediated cytopathogenicity against host cells.

    CONCLUSION: These results demonstrate that PPy-Co3O4-AgNPs hold promise in the development of novel antimicrobial nanomaterials for biomedical applications.

    KEY POINTS: •Synthesis of polypyrrole-cobalt oxide-silver (PPy-Co3O4-AgNPs) nanocomposite. •Antimicrobial activity of nanocomposite. •PPy-Co3O4-AgNPs hold promise for biomedical applications.

    Matched MeSH terms: Oxides
  19. Khaniabadi PM, Shahbazi-Gahrouei D, Aziz AA, Dheyab MA, Khaniabadi BM, Mehrdel B, et al.
    Photodiagnosis Photodyn Ther, 2020 Sep;31:101896.
    PMID: 32585402 DOI: 10.1016/j.pdpdt.2020.101896
    BACKGROUND: Theranostic agents can combine photosensitizers and contrast agents into a single unit for photothermal therapy (PTT) and magnetic resonance imaging (MRI). The possibility of treating and diagnosing malignant cancers without any ionizing radiation could become an option. This study investigates the theranostic potential of Fe3O4 nanoparticles (IONs) for the diagnosis and treatment of cancer by developing a single integrated nanoprobe.

    METHODS: Oleylamin-coated IONs (ION-Ol) were synthesized and surface of the IONs was modified using protoporphyrin (PP) and trastuzumab (TZ) to develop the TZ-conjugated SPION-porphyrin [ION-PP-TZ]. The structure, morphology, size, and cytotoxicity of all samples were investigated using Fourier-transform infrared spectroscopy (FT-IR), Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), WST-1 assay, respectively. In addition to MRI and in vitro laser irradiation (808 nm, 200 mW) to determine the r2 values and photothermal ablation.

    RESULTS: The sizes of monodispersed nanoparticles were measured in rang 5.74-7.17 nm. No cytotoxicity was observed after incubating MCF 7 cells under various Fe concentrations of nanoparticles and theranostic agents. The transverse relaxation time of the protoporphyrin conjugated to IONs (52.32 mM-1s-1) exceeded that of ION-Ol and TZ-conjugated ION-PP. In addition, the in vitro photothermal ablation of ION-PP-TZ revealed a 74 % MCF 7 cell reduction after 10 min of at the highest Fe concentration (1.00 mg Fe/mL).

    CONCLUSIONS: In summary, the water-soluble ION-PP-TZ is a promising bimodal agent for the diagnosis and treatment of human epidermal growth factor receptor 2-positive breast cancer cells using a T2 MRI contrast agent and photothermal therapy.

    Matched MeSH terms: Oxides
  20. Hadijah, H., Norazlanshah, H., Muhammad, I., Roowi, S.
    MyJurnal
    The interest in dietary antioxidants which are mainly found in fruits, has prompted research in
    the field of commercial high antioxidant juice for healthy purposes. Fruits also are rich with antioxidants that help in reducing of degenerative diseases such as cancer, arthritis, cardiovascular
    disease and inflammation. Based on the health claims from the natural antioxidants, a new healthy juice called Mixed Fruit Juice (MFJ) has been developed by using three combinations of local fruits (soursop, mango and kasturi lime). In order to promote the commercial use of this product, the safety evaluation is needed to be carried out. The 28-days repeated toxicity test has been conducted in female and male rats for pre-clinical safety assessment prior to human study. There was no mortality observed when varying doses of the MFJ (5, 10 and 20%) administered to all rats. Hematological analysis showed no significant differences in most parameters examined. There were no significant changes observed in the liver and kidney functions tests of all treated-rats as compared to control normal rats. Furthermore, lipid profiles and blood glucose level were also within the normal range as noted in control rats. The present data demonstrate that the supplementation of MFJ did not produce adverse effects on the body system of experimental rats. This is the first documented report on the safety assessment of
    MFJ in rats.
    Matched MeSH terms: Oxides
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