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Species richness of riparian vegetation after three decades of Kenyir dam establishment

Shahimi S, Salam R, Salim JM, Ahmad A

Data Brief, 2019 Aug;25:104045.
PMID: 31194175 DOI: 10.1016/j.dib.2019.104045

This data article is on riparian vegetation species richness in four different streams located in the Sultan Mahmud Hydroelectric dam, also known as Kenyir dam and commonly referred to as Tasik Kenyir, Terengganu. The dataset consists of three reservoir-island streams and the other is a small stream located on the mainland. A total of 41 families and 90 species of riparian plants were reported for the first time after 34 years of the establishment of the Sultan Mahmud Hydroelectric dam. Trees contributing 60% of the species recorded in this study and the others were non-tree species, including climbers, ferns, epiphyte, herbs, shrub, strangling trees and palms. Among the recorded riparian plant species, two are introduced which are Clidemia hirta and Mimosa pigra. The highest diversity of riparian plant found in the stream of Sungai Kiang, followed by Sungai Ikan and Sungai Saok with 46, 29 and 17 species respectively for the reservoir-island streams. The mainland stream, Sungai Siput recorded 37 species. These riparian plants provide important ecosystem services, among others soil stabilization, habitat and food for aquatic fauna and water filtration. In terms of plant utilization potential and values, 47 species are identified having medicinal value, 10 species with ornamental value and another 36 species are timber trees. Our study demonstrates that the riparian plants are closely linked to stream size with variability associated with types of stream systems. The data collected also demonstrates that the riparian plant community is at the seral stages of riparian forest. This is indicated by the increase in plant species richness as the vegetation gradually changes from riparian towards mature forest composition. To secure ecological functions of Tasik Kenyir riparian plant assemblages, particularly in stabilizing the lake's margin and riverbank, it is recommended that monitoring and legal protection may need to be imposed by local authority.

Matched MeSH terms: Zinc Oxide
Solar photocatalytic degradation of 2-chlorophenol with ZnO nanoparticles: optimisation with D-optimal design and study of intermediate mechanisms

Ba-Abbad MM, Takriff MS, Kadhum AA, Mohamad AB, Benamor A, Mohammad AW

Environ Sci Pollut Res Int, 2017 Jan;24(3):2804-2819.
PMID: 27837474 DOI: 10.1007/s11356-016-8033-y

In this study, the photocatalytic degradation of toxic pollutant (2-chlorophenol) in the presence of ZnO nanoparticles (ZnO NPs) was investigated under solar radiation. The three main factors, namely pH of solution, solar intensity and calcination temperature, were selected in order to examine their effects on the efficiency of the degradation process. The response surface methodology (RSM) technique based on D-optimal design was applied to optimise the process. ANOVA analysis showed that solar intensity and calcination temperature were the two significant factors for degradation efficiency. The optimum conditions in the model were solar intensity at 19.8 W/m(2), calcination temperature at 404 °C and pH of 6.0. The maximum degradation efficiency was predicted to be 90.5% which was in good agreement with the actual experimental value of 93.5%. The fit of the D-optimal design correlated very well with the experimental results with higher values of R (2) and R (2)adj correlation coefficients of 0.9847 and 0.9676, respectively. The intermediate mechanism behaviour of the 2-chlorophenol degradation process was determined by gas chromatography-mass spectrometry (GC-MS). The results confirmed that 2-chlorophenol was converted to acetic acid, a non-toxic compound.

Matched MeSH terms: Zinc Oxide
Fulltext Simple Response Surface Methodology: Investigation on Advance Photocatalytic Oxidation of 4-Chlorophenoxyacetic Acid Using UV-Active ZnO Photocatalyst

Lee KM, Hamid SBA

Materials (Basel), 2015 Jan 19;8(1):339-354.
PMID: 28787941 DOI: 10.3390/ma8010339

The performance of advance photocatalytic degradation of 4-chlorophenoxyacetic acid (4-CPA) strongly depends on photocatalyst dosage, initial concentration and initial pH. In the present study, a simple response surface methodology (RSM) was applied to investigate the interaction between these three independent factors. Thus, the photocatalytic degradation of 4-CPA in aqueous medium assisted by ultraviolet-active ZnO photocatalyst was systematically investigated. This study aims to determine the optimum processing parameters to maximize 4-CPA degradation. Based on the results obtained, it was found that a maximum of 91% of 4-CPA was successfully degraded under optimal conditions (0.02 g ZnO dosage, 20.00 mg/L of 4-CPA and pH 7.71). All the experimental data showed good agreement with the predicted results obtained from statistical analysis.

Matched MeSH terms: Zinc Oxide
Fulltext Shape-dependent antibacterial activity against escherichia coli of zinc oxide nanoparticles

Nor Hazliana Harun, Mydin, Rabiatul Basria S.M.N., Sreekantan, Srimala, Khairul Arifah Saharudin, Norfatehah Basiron, Fakrul Radhi, et al.

Journal of Biomedical and Clinical Sciences, 2018;3(2):35-38.
MyJurnal

Zinc oxide (ZnO) nanoparticles (NPs) has become as promising candidate for antibacterial agents against Escherichia coli (E.coli), commensal hospital- acquired infections (HAIs). This study investigates the antibacterial action of ZnO NPs in three difference shapes; nanorod, nanoflakes and nanospheres against E.coli ATCC 25922. The antibacterial activity of ZnO NPs was determine through two standard protocols known as Clinical Laboratory Standards Institute (CLSI) MO2-A11 under light conditions of 5.70 w/m2 and American standard test method (ASTM) E-2149. Preliminary screening shows ZnO NPs did not inhibit the growth of E.coli. Further analysis using ASTM E-2149 in dynamic conditions revealed antibacterial activity after 3 hours with 100% reduction for ZnO NPs nanoflakes and 6 hours with 94.63% reduction for ZnO nanospheres, respectively. It demonstrated the ZnO NPs in nanoflakes and nanospheres exerted higher antibacterial activity possibly through release of ios, free radicals, ROS generation and electrostatic collision which contribute to bacterial death. Further analysis is needed to investigate biocompatibility of these samples for future biomedical applications.

Matched MeSH terms: Zinc Oxide
Fulltext Shape-Dependent antibacterial activity against Staphylococcus aureus of Zinc Oxide Nanoparticles

Nor Hazliana Harun, Rabiatul Basria S. M. N. Mydin, Khairul Arifah Saharudin, Sreekantan, Srimala, Khor Yong Ling, Norfatehah Basiron, et al.

Malaysian Journal of Medicine and Health Sciences, 2018;14(102):1-6.
MyJurnal

There is a growing concern in using zinc oxide nanoparticles (ZnO NPs) for medical devices as alternative options in reducing hospital-acquired infections (HAIs). The commensal HAIs; Staphylococcus aureus (S.aureus) infect patients and lead to increased rates of morbidity and mortality. This study aims to investigate the antibacterial action of ZnO NPs in three different shapes; nanorod, nanoflakes and nanospheres impregnated in low-density polyethylene (LDPE) against S.aureus ATCC 25923. Methods: The antibacterial efficiency of ZnO NPs was studied through two standard test methods included were based on Clinical Laboratory Standards Institute (CLSI) guidelines MO2-A11 under light conditions of 5.70 w/m2 and American standard test method (ASTM) E-2149. Results: Preliminary screening did show a significant growth inhibition against S.aureus with ZnO NPs nanorod and nanoflakes, approximately in 7 to 8 mm zones of inhibition. Further analysis using ASTM E-2149 in dynamic conditions revealed variable activity depending on incubation treatment periods. It demonstrated the ZnO NPs in nanoflakes and nanosphere shape showed better inhibition against S.aureus with maximum reduction (100%). The FESEM results strongly suggest that the structure of ZnO nanoflakes and nanosphere played an importance role in nanomaterial-bacteria interaction which consequently cause cell membrane damage. Additionally, the irradiation under light treatment also enhance the generation of ROS and free radicals which helps the bactericidal activity against S.aureus. Conclusion: This study provides new insights for the antibacterial action of ZnO NPs/LDPE thin films in future biomedical appliances to reduce HAIs risks.

Matched MeSH terms: Zinc Oxide
Shape-Controlled Fabrication of ZnO Architectures for Palm Oil Mill Effluent Degradation

Wong KA, Lam SM, Sin JC

J Nanosci Nanotechnol, 2019 08 01;19(8):5271-5278.
PMID: 30913844 DOI: 10.1166/jnn.2019.16816

Shaped-controlled ZnO architectures including spherical, rod, rice-like and flower-like were fabricated via a reflux method in which the morphology, crystallinity, functional group and optical properties were tailored under different pH values in the precursor solution. The photoactivities of the prepared ZnO were evaluated under UV irradiation and the findings implied that the flower-like ZnO synthesized at pH 12 displayed superior activities on palm oil mil effluent degradation than those of other structures. The photocatalytic enhancement of flower-like ZnO was ascribed to its unique architecture, good crystallinity and superior optical properties. The flower-like ZnO with excellent photocatalytic performance have been confirmed by formation of hydroxyl radicals using a terephthalic acid-photoluminescence test. There was an optimal photocatalyst amount of 1.0 g/L, at which a maximum chemical oxygen demand removal of palm oil mill effluent was achieved under exposure of UV light. The phytotoxicity experiment via mung beans demonstrated a decrease in phytotoxicity.

Matched MeSH terms: Zinc Oxide
Sensitivity enhancement of graphene/zinc oxide nanocomposite-based electrochemical impedance genosensor for single stranded RNA detection

Low SS, Loh HS, Boey JS, Khiew PS, Chiu WS, Tan MTT

Biosens Bioelectron, 2017 Aug 15;94:365-373.
PMID: 28319904 DOI: 10.1016/j.bios.2017.02.038

An efficient electrochemical impedance genosensing platform has been constructed based on graphene/zinc oxide nanocomposite produced via a facile and green approach. Highly pristine graphene was synthesised from graphite through liquid phase sonication and then mixed with zinc acetate hexahydrate for the synthesis of graphene/zinc oxide nanocomposite by solvothermal growth. The as-synthesised graphene/zinc oxide nanocomposite was characterised with scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and X-ray diffractometry (XRD) to evaluate its morphology, crystallinity, composition and purity. An amino-modified single stranded DNA oligonucleotide probe synthesised based on complementary Coconut Cadang-Cadang Viroid (CCCVd) RNA sequence, was covalently bonded onto the surface of graphene/zinc oxide nanocomposite by the bio-linker 1-pyrenebutyric acid N-hydroxysuccinimide ester. The hybridisation events were monitored by electrochemical impedance spectroscopy (EIS). Under optimised sensing conditions, the single stranded CCCVd RNA oligonucleotide target could be quantified in a wide range of 1.0×10-11M to 1.0×10-6 with good linearity (R =0.9927), high sensitivity with low detection limit of 4.3×10-12M. Differential pulse voltammetry (DPV) was also performed for the estimation of nucleic acid density on the graphene/zinc oxide nanocomposite-modified sensing platform. The current work demonstrates an important advancement towards the development of a sensitive detection assay for various diseases involving RNA agents such as CCCVd in the future.

Matched MeSH terms: Zinc Oxide/chemistry
Fulltext Seed/catalyst-free vertical growth of high-density electrodeposited zinc oxide nanostructures on a single-layer graphene

Aziz NS, Mahmood MR, Yasui K, Hashim AM

Nanoscale Res Lett, 2014 Feb 26;9(1):95.
PMID: 24568668 DOI: 10.1186/1556-276X-9-95

We report the seed/catalyst-free vertical growth of high-density electrodeposited ZnO nanostructures on a single-layer graphene. The absence of hexamethylenetetramine (HMTA) and heat has resulted in the formation of nanoflake-like ZnO structure. The results show that HMTA and heat are needed to promote the formation of hexagonal ZnO nanostructures. The applied current density plays important role in inducing the growth of ZnO on graphene as well as in controlling the shape, size, and density of ZnO nanostructures. High density of vertically aligned ZnO nanorods comparable to other methods was obtained. The quality of the ZnO nanostructures also depended strongly on the applied current density. The growth mechanism was proposed. According to the growth timing chart, the growth seems to involve two stages which are the formation of ZnO nucleation and the enhancement of the vertical growth of nanorods. ZnO/graphene hybrid structure provides several potential applications in electronics and optoelectronics such as photovoltaic devices, sensing devices, optical devices, and photodetectors.

Matched MeSH terms: Zinc Oxide
Sealing ability of various restorative materials as coronal barriers between endodontic appointments

Tapsir Z, Aly Ahmed HM, Luddin N, Husein A

J Contemp Dent Pract, 2013 Jan 1;14(1):47-50.
PMID: 23579892

To evaluate and compare the microleakage of various restorative materials used as coronal barriers between endodontic appointments.

Matched MeSH terms: Zinc Oxide/chemistry
Fulltext SYNTHESIS OF ZINC OXIDE NANOPARTICLES BY USING ALOE VERA LEAF EXTRACT AS PONTENTIAL ANODE MATERIAL IN LITHIUM ION BATTERY

SITI RABIATUL ADAWIYAH MAZLI, HANIS MOHD YUSOFF, NURUL HAYATI IDRIS

UMT Journal of Undergraduate Research, 2020;2(2):0-0.
MyJurnal

Synthesis of nanoparticles by using plant have sparked interest among researchers due to environmentally safe, inexpensive and simple method to compare with chemical method. Use of plant in synthesis zinc oxide nanoparticles (ZnO NPs) that act as reducing and capping agent are more recommended, due to high production of product and rate of synthesis is faster than using microorganism. This study focus on the synthesis of ZnO NPs by using leaf extract of aloe vera (Aloe bardenisis miller) with different concentration (30%, 40% and 50%) and various calcination temperature which are 500 ˚C, 700 ˚C and 900 ˚C for 4 hours. Fourier – transform infrared spectroscopy (FTIR), Thermogravimetric Analysis (TGA), scanning electron microscopy (SEM), X-ray Diffraction (XRD) and Brunauer-Emmet and Teller (BET) were used to characterize the prepared samples. FTIR spectra showed present wavenumber in between 400-500 cm-1 indicated the presence of Zn-O stretch. Powder XRD pattern confirmed the hexagonal wurtzite structure with average particles size from 24.19 nm to 67.69 nm for all concentration and temperature by using Scherer’s equation. For SEM analysis the images show irregular shape for concentrations 30% and 50% with size range from 500 nm to 900 nm while for concentration 40% cubic shape was observe with size range from 140 nm to 900 nm. All characterize show that formation of ZnO NPs depend on the concentration and calcination temperature. Sample 30% and 50% ZnO NPs was applied in lithium battery at voltage from 0.01 to 3. 1.2 mAhg-1 was recorded for sample 30% ZnO NPs while 100 mAhg-1.

Matched MeSH terms: Zinc Oxide
Fulltext SYNTHESIS AND CHARACTERIZATION OF TiO2/ZnO-EPOXY BEADS AND THEIR PERFORMANCE FOR THE DEGRADATION OF DYE

MOHAMAD HANIF AKMAL HUSSIN, WAN RAFIZAH WAN ABDULLAH, MOHAMAD AWANG

UMT Journal of Undergraduate Research, 2020;2(2):9-14.
MyJurnal

Semiconductor oxides such as titanium dioxide (TiO2) and zinc oxide (ZnO) are used as the photocatalyst for removing contaminants. In addition, TiO2 and ZnO nanoparticles in the suspension form makes it difficult to be recovered and recycled. This study was conducted to investigate the efficiency of immobilizing TiO2 and ZnO nanoparticles in epoxy beads. The immobilization process using different ratios of photocatalysts TiO2/ZnO (1:0, 3:1, 1:1, 1:3 and 0:1) fixed on epoxy material. These epoxy beads were used for dye removal in photocatalysis using methylene blue (MB) solution at a concentration of 10mg/L. Besides, epoxy beads also characterized using scanning electron microscope (SEM), attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and thermogravimetric analysis (TGA). The results showed that the highly recommended epoxy bead is 3:1 ratio of TiO2/ZnO because it has good performance in dye degradation that proved from reducing concentration of MB to 2.4mg/L (76%). However, TiO2/ZnO characterization of 3:1 by SEM show on the surface the particle are found to be spherical in shape which is relatively high efficiency for the degradation, ATR-FTIR pattern in broad band 4000 cm-1 - 400cm-1 which correspond to hydroxyl stretching to be adsorbed at peak (474.49 cm-1 - 3722.61cm-1) respectively to the optimum for the degradation and TGA rate of change are 5mg to 2.5mg that residue (49.78%) due to decomposition or oxidation from mass loss. These findings are very effective and economical technique to be cost saving and highly efficient photocatalyst.

Matched MeSH terms: Zinc Oxide
Fulltext SOLAR PHOTOCATALYTIC EFFICIENCY OF ZINC OXIDE FOR WATER DECONTAMINATION

FARAH EILYANA MOHAMED

UMT Journal of Undergraduate Research, 2019;1(1):92-102.
MyJurnal

Solar photocatalysis is a green technology that takes advantage of sustainable solar energy for enhancing oxidation process of numerous harmful water contaminants. In this study, a custom solar driven zinc oxide (ZnO)-mediated photocatalytic system was developed and its efficiency to remove organic contaminants as well as to disinfect selected bacteria was investigated. Methylene blue (MB) dye was used as the model organic contaminant, while Escherichia coli(E.coli) was used as the model fecal coliform bacteria in contaminated water. A series of photodegradation experiments were conducted on water contaminated with either 10 mg/L of MB or ~1010CFU/ml of E.coli. The experiments were completed under sunlight irradiation in the presence of 1 g/L of nano ZnO photocatalyst for up to 6 hours. Using a solar thermal collector, the photoreactor operated in the temperature range of 25 to 50 oC. The findings revealed that the combination of solar thermal with solar photocatalysis usingZnO intensified the degradation of MB and disinfection of E.coli. 98.08% of MB dye and 99.99% of E.coliwere successfully removed from the water within the first 3 hours of treatment. Almost complete removal was eventually achieved after 6 hours of treatment. It is therefore suggested that ZnO-based solar photocatalytic system developed in this study is highly efficient at enhancing water decontamination process.

Matched MeSH terms: Zinc Oxide
Fulltext Role of morphological structure, doping, and coating of different materials in the sensing characteristics of humidity sensors

Tripathy A, Pramanik S, Cho J, Santhosh J, Osman NA

Sensors (Basel), 2014;14(9):16343-422.
PMID: 25256110 DOI: 10.3390/s140916343

The humidity sensing characteristics of different sensing materials are important properties in order to monitor different products or events in a wide range of industrial sectors, research and development laboratories as well as daily life. The primary aim of this study is to compare the sensing characteristics, including impedance or resistance, capacitance, hysteresis, recovery and response times, and stability with respect to relative humidity, frequency, and temperature, of different materials. Various materials, including ceramics, semiconductors, and polymers, used for sensing relative humidity have been reviewed. Correlations of the different electrical characteristics of different doped sensor materials as the most unique feature of a material have been noted. The electrical properties of different sensor materials are found to change significantly with the morphological changes, doping concentration of different materials and film thickness of the substrate. Various applications and scopes are pointed out in the review article. We extensively reviewed almost all main kinds of relative humidity sensors and how their electrical characteristics vary with different doping concentrations, film thickness and basic sensing materials. Based on statistical tests, the zinc oxide-based sensing material is best for humidity sensor design since it shows extremely low hysteresis loss, minimum response and recovery times and excellent stability.

Matched MeSH terms: Zinc Oxide/chemistry*
Role of dissolved oxygen on the degradation mechanism of Reactive Green 19 and electricity generation in photocatalytic fuel cell

Lee SL, Ho LN, Ong SA, Wong YS, Voon CH, Khalik WF, et al.

Chemosphere, 2018 Mar;194:675-681.
PMID: 29247929 DOI: 10.1016/j.chemosphere.2017.11.166

In this study, a membraneless photocatalytic fuel cell with zinc oxide loaded carbon photoanode and platinum loaded carbon cathode was constructed to investigate the impact of dissolved oxygen on the mechanism of dye degradation and electricity generation of photocatalytic fuel cell. The photocatalytic fuel cell with high and low aeration rate, no aeration and nitrogen purged were investigated, respectively. The degradation rate of diazo dye Reactive Green 19 and the electricity generation was enhanced in photocatalytic fuel cell with higher dissolved oxygen concentration. However, the photocatalytic fuel cell was still able to perform 37% of decolorization in a slow rate (k = 0.033 h-1) under extremely low dissolved oxygen concentration (approximately 0.2 mg L-1) when nitrogen gas was introduced into the fuel cell throughout the 8 h. However, the change of the UV-Vis spectrum indicates that the intermediates of the dye could not be mineralized under insufficient dissolved oxygen level. In the aspect of electricity generation, the maximum short circuit current (0.0041 mA cm-2) and power density (0.00028 mW cm-2) of the air purged photocatalytic fuel cell was obviously higher than that with nitrogen purging (0.0015 mA cm-2and 0.00008 mW cm-2).

Matched MeSH terms: Zinc Oxide
Recent developments of zinc oxide based photocatalyst in water treatment technology: A review

Lee KM, Lai CW, Ngai KS, Juan JC

Water Res, 2016 Jan 01;88:428-448.
PMID: 26519627 DOI: 10.1016/j.watres.2015.09.045

Today, a major issue about water pollution is the residual dyes from different sources (e.g., textile industries, paper and pulp industries, dye and dye intermediates industries, pharmaceutical industries, tannery and craft bleaching industries, etc.), and a wide variety of persistent organic pollutants have been introduced into our natural water resources or wastewater treatment systems. In fact, it is highly toxic and hazardous to the living organism; thus, the removal of these organic contaminants prior to discharge into the environment is essential. Varieties of techniques have been employed to degrade those organic contaminants and advanced heterogeneous photocatalysis involving zinc oxide (ZnO) photocatalyst appears to be one of the most promising technology. In recent years, ZnO photocatalyst have attracted much attention due to their extraordinary characteristics. The high efficiency of ZnO photocatalyst in heterogeneous photocatalysis reaction requires a suitable architecture that minimizes electron loss during excitation state and maximizes photon absorption. In order to further improve the immigration of photo-induced charge carriers during excitation state, considerable effort has to be exerted to further improve the heterogeneous photocatalysis under UV/visible/solar illumination. Lately, interesting and unique features of metal doping or binary oxide photocatalyst system have gained much attention and became favourite research matter among various groups of scientists. It was noted that the properties of this metal doping or binary oxide photocatalyst system primarily depend on the nature of the preparation method and the role of optimum dopants content incorporated into the ZnO photocatalyst. Therefore, this paper presents a critical review of recent achievements in the modification of ZnO photocatalyst for organic contaminants degradation.

Matched MeSH terms: Zinc Oxide/chemistry*
Prevention of coronal discoloration induced by root canal sealer remnants using Dentin Bonding agent: An in vitro study

Khim TP, Sanggar V, Shan TW, Peng KC, Western JS, Dicksit DD

J Conserv Dent, 2018 10 9;21(5):562-568.
PMID: 30294122 DOI: 10.4103/JCD.JCD_115_18

Introduction: Among the various causes of tooth discoloration after root canal treatment, percolation of sealer remnants into the dentinal tubules of the pulp chamber is the most common cause.
Objectives: The aim of this study is to evaluate the efficacy of dentin bonding agent (DBA) in preventing coronal discoloration caused by four different root canal sealers- MTA Fillapex, Sealapex, Zical and Z. O. B seal at different time intervals by measuring chromatic alterations using digital images analysis method.
Methodology: Ninety mandibular premolars were collected and sectioned at 1 mm below the cementoenamel junction. Standard access cavity preparations of dimensions (depth-3 mm, width-0.8 mm, and length-3 mm) were prepared with a No. 245 bur through the cervical access. Following the standard irrigation protocol, specimens were then randomly divided into nine groups (four groups without DBA [1-4] +4 groups with DBA [5-8] +1 negative control [9]). In Groups 1-4, four different root canal sealers (MTA Fillapex, Sealapex, Zical, and Z.O.B seal) were applied to the walls of the pulp chamber. For Groups 5-8, the samples were etched with 37% phosphoric acid and DBA application was done before the respective root canal sealer application. The cervical access in all specimens was sealed using glass ionomer cement. Digital photographs were taken under standard lighting and environmental conditions at different time intervals: preprocedural, postprocedural, and after 1, 2, 3, and 4 months. These images were analyzed using Adobe Photoshop CS6 from which laboratory values and subsequently Delta E values were obtained.
Results: Statistical analysis performed using repeated measures ANOVA and post hoc Tukey's tests show that the groups with DBA application had significantly lower mean Delta E values (P < 0.05) compared to the groups without DBA application.
Conclusion: DBAs applied to the dentinal walls of the pulp chamber before obturation can effectively reduce the sealer-induced coronal discoloration.

Matched MeSH terms: Zinc Oxide-Eugenol Cement
Fulltext Preparation and properties of poly(vinyl alcohol)/chitosan blend bionanocomposites reinforced with cellulose nanocrystals/ZnO-Ag multifunctional nanosized filler

Azizi S, Ahmad MB, Hussein MZ, Ibrahim NA, Namvar F

Int J Nanomedicine, 2014;9:1909-17.
PMID: 24790433 DOI: 10.2147/IJN.S60274

A series of novel bionanocomposites were cast using different contents of zinc oxide-silver nanoparticles (ZnO-AgNPs) stabilized by cellulose nanocrystals (CNC) as multifunctional nanosized fillers in poly(vinyl alcohol)/chitosan (PVA/Cs) matrices. The morphological structure, mechanical properties, ultraviolet-visible absorption, and antimicrobial properties of the prepared films were investigated as a function of their CNC/ZnO-AgNP content and compared with PVA/chitosan/CNC bionanocomposite films. X-ray diffraction and field emission scanning electron microscopic analyses showed that the CNC/ZnO-AgNPs were homogeneously dispersed in the PVA/Cs matrix and the crystallinity increased with increasing nanosized filler content. Compared with pure PVA/Cs, the tensile strength and modulus in the films increased from 0.055 to 0.205 GPa and from 0.395 to 1.20 GPa, respectively. Ultraviolet and visible light can be efficiently absorbed by incorporating ZnO-AgNPs into a PVA/Cs matrix, suggesting that these bionanocomposite films show good visibility and ultraviolet-shielding effects. The bionanocomposite films had excellent antimicrobial properties, killing both Gram-negative Salmonella choleraesuis and Gram-positive Staphylococcus aureus. The enhanced physical properties achieved by incorporating CNC/ZnO-AgNPs could be beneficial in various applications.

Matched MeSH terms: Zinc Oxide/pharmacology; Zinc Oxide/chemistry
Fulltext Preparation and characterization of an anti-inflammatory agent based on a zinc-layered hydroxide-salicylate nanohybrid and its effect on viability of Vero-3 cells

Ramli M, Hussein MZ, Yusoff K

Int J Nanomedicine, 2013;8:297-306.
PMID: 23345976 DOI: 10.2147/IJN.S38858

A new organic-inorganic nanohybrid based on zinc-layered hydroxide intercalated with an anti-inflammatory agent was synthesized through direct reaction of salicylic acid at various concentrations with commercially available zinc oxide. The basal spacing of the pure phase nanohybrid was 15.73 Å, with the salicylate anions arranged in a monolayer form and an angle of 57 degrees between the zinc-layered hydroxide interlayers. Fourier transform infrared study further confirmed intercalation of salicylate into the interlayers of zinc-layered hydroxide. The loading of salicylate in the nanohybrid was estimated to be around 29.66%, and the nanohybrid exhibited the properties of a mesoporous-type material, with greatly enhanced thermal stability of the salicylate compared with its free counterpart. In vitro cytotoxicity assay revealed that free salicylic acid, pure zinc oxide, and the nanohybrid have a mild effect on viability of African green monkey kidney (Vero-3) cells.

Matched MeSH terms: Zinc Oxide/pharmacology; Zinc Oxide/chemistry
Fulltext Preparation and Evaluation of the ZnO NP-Ampicillin/Sulbactam Nanoantibiotic: Optimization of Formulation Variables Using RSM Coupled GA Method and Antibacterial Activities

Sharma N, Singh V, Pandey AK, Mishra BN, Kulsoom M, Dasgupta N, et al.

Biomolecules, 2019 11 21;9(12).
PMID: 31766572 DOI: 10.3390/biom9120764

Nanoparticles (NPs) possessing antibacterial activity represent an effective way of overcoming bacterial resistance. In the present work, we report a novel formulation of a nanoantibiotic formed using Ampicillin/sulbactam (Ams) and a zinc oxide nanoparticle (ZnO NP). 'ZnO NP-Ams' nanoantibiotic formulation is optimized using response surface methodology coupled genetic algorithm approach. The optimized formulation of nanoantibiotic (ZnO NP: 49.9 μg/mL; Ams: 33.6 μg/mL; incubation time: 27 h) demonstrated 15% enhanced activity compared to the unoptimized formulation against K. pneumoniae. The reactive oxygen species (ROS) generation was directly proportional to the interaction time of nanoantibiotic and K. pneumoniae after the initial lag phase of ~18 h as evident from 2'-7'-Dichlorodihydrofluorescein diacetate assay. A low minimum inhibitory concentration (6.25 μg/mL) of nanoantibiotic formulation reveals that even a low concentration of nanoantibiotic can prove to be effective against K. pneumoniae. The importance of nanoantibiotic formulation is also evident by the fact that the 100 μg/mL of Ams and 25 µg of ZnO NP was required individually to inhibit the growth of K. pneumonia, whereas only 6.25 μg/mL of optimized nanoantibiotic formulation (ZnO NP and Ams in the ratio of 49.9: 33.6 in μg/mL and conjugation time of 27 h) was needed for the same.

Matched MeSH terms: Zinc Oxide/pharmacology*
Fulltext Postoperative assessment of diode laser zinc oxide eugenol and mineral trioxide aggregate pulpotomy procedures in children: A comparative clinical study

Pratima B, Chandan GD, Nidhi T, Nitish I, Sankriti M, Nagaveni S, et al.

J Indian Soc Pedod Prev Dent, 2018 9 25;36(3):308-314.
PMID: 30246755 DOI: 10.4103/JISPPD.JISPPD_1132_17

Aim: The present study is an attempt to compare and evaluate postoperative assessment of diode laser zinc oxide eugenol (ZOE) pulpotomy and diode laser mineral trioxide aggregate (MTA) pulpotomy procedures in children.
Materials and Methods: Forty carious primary molars indicated for pulpotomy within the age group of 4-9 years were selected and divided into two groups of 20 each using simple randomization, Group 1: Diode laser MTA and Group 2: Diode laser ZOE pulpotomy. The teeth were evaluated clinically for 1 year at 3, 6, and 12 months interval and radiologically for 6 and 12 months.
Results: Clinically and radiographically, 100% teeth treated with diode laser MTA and 94% treated with diode laser ZOE were considered successful after 12-month follow-up interval. No significant difference was seen between two groups.
Conclusion: Despite the success rate, the cost factor of diode laser and MTA could be the limiting factor in its judicious use in pulpotomy procedure.

Matched MeSH terms: Zinc Oxide-Eugenol Cement/therapeutic use*

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