research centers


Search results: Found 4

Listing 1 - 4 of 4
Sort by

Article
The Effect of Zinc Oxide Nanoparticles on Streptococcus mutans of Human Saliva (In Vitro Study)

Authors: Suha T. Abd --- Abbas F. Ali عباس فاضل
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 2 Pages: 158-164
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

Background: Nanotechnology represents a new science that promises to provide a broad range of uses andimproved technologies for biological and biomedical applications. One of the reasons behind the intense interest isthat nanotechnology permits synthesis of materials that have structure is less than 100 nanometers. The present workrevealed the effect of zinc oxide nanoparticles (ZnO NPs) on Streptococcus mutans of Human Saliva in comparisonto de-ionized water.Materials and methods: Streptococcus mutans were isolated from saliva of forty eight volunteers of both sexes theirage range between 18-22 years and then purified and diagnosed according to morphological characteristic andbiochemical tests. Different concentrations of ZnO NPs were prepared from the stock solution; all the experimentswere conducted in vitro. Disk diffusion method was used to study the sensitivity of Streptococcus mutans to differentconcentrations of zinc oxide nanoparticles in comparison to effect of de-ionized water.Results: Streptococcus mutans were sensitive to concentrations (0.05, 0.1, 0.5, 1, 3 and 5.8) mg / ml of the zinc oxidenanoparticles solution in comparison to de-ionized water, revealing a highly significant difference in allconcentrations except for concentration (0.01) mg / ml which was showed no significant difference in comparison tode-ionized water.Conclusion: This study revealed that zinc oxide nanoparticles were effective against Streptococcus mutans


Article
Effect of zinc oxide nanoparticles on total salivary peroxidase activity of human saliva (In vitro study)

Authors: Suha T. Abd --- Abbas F. Ali
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 2 Pages: 178-182
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

Background: The potential use of zinc oxide and other metal oxide nanoparticles in biomedical are gaining interestin the scientific and medical communities, largely due to the physical and chemical properties of thesenanomaterials. The present work revealed the effect of zinc oxide nanoparticles (ZnONPs) on the total salivaryperoxidase enzyme activity of human saliva in comparison to de-ionized water.Materials and methods: Forty eight unstimulated saliva samples were collected from dental students/University ofBaghdad 18-22 years. Then measure the total salivary peroxidase activity first without any addition to human saliva asa control, second with dilution the saliva with de-ionized water, and third with zinc oxide nanoparticles inconcentration (5.8 mg/ml).Results: The results showed that there was significant inhibition of the activity of the total salivary peroxidase enzymein the presence ZnO NPs and non-significant inhibition of enzyme activity in the presence de-ionized as comparedwith control group.Conclusion: Zinc oxide nanoparticles have inhibition effect on total salivary peroxidase activity


Article
Synthesis and Antibacterial Activity of ZnO Nanoparticles Using the Precipitate and Irradiation Methods

Author: Athraa S. Ahmed , Shaimaa H. Jaber , Barakat A. F. Kamel , Kafi M. Dawood
Journal: Iraqi Journal of Biotechnology المجلة العراقية للتقانات الحياتية ISSN: 18154794 Year: 2019 Volume: 18 Issue: 2 Pages: 88-94
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

In this study, ZnO NPS were synthesized in two methods: the precipitate and irradiation methods. X-Ray powder Diffraction, Transmission and Scanning Electron Microscopy were used to study the crystal structure and surface morphology of the synthesized NPS, which showed that the average particle size of ZnO NPS synthesized by irradiation method was better than which synthesized by precipitate method. The antibacterial activity against staphylococcus epidermidis and E.coli bacteria were studied and showed that ZnO NPs prepared by Irradiation method have higher antibacterial activity against S.epidermidis and E.coli than ZnO NPs prepared by precipitate method because of ZnO NPs prepared by Irradiation method smaller than ZnO NPs prepared by precipitate method. In current study, we concluded that irradiation method is better than precipitate method in the preparation of ZnO NPS and in the inhibition of the work of types of bacteria such as (staphylococcus epidermidis and E.coli).


Article
Synthesis and Characterization of Zno Nanoparticles Using Hydrothermal and Sol-GelTechniques for Dye-Sensitized Solar Cells

Authors: H. Musleh --- N. AlDahoudi --- H.Zayed --- S. Shaat --- et al.
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2018 Volume: 26 Issue: 9 Pages: 256-267
Publisher: Babylon University جامعة بابل

Loading...
Loading...
Abstract

ZnO nanoparticles (ZnONPs) were synthesized using hydrothermal and sol-gel techniques using zinc acetate dihydrate (Zn (CH3COO)2.2H2O) as a row material and methanol as a solvent. The structural properties of ZnO NPs were studied using EDX, XRD, TEM, and the optical properties were characterized using UV-VIS and PL spectroscopies. The synthesized ZnO NPs showed high purity and revealed a wurtzite (hexagonal) crystal structure with particle size (D) ranged from 25 nm to 28 nm. The UV-VIS absorption spectra of ZnO NPs samples and sensitizing dyes were performed. The obtained ZnO NPs exhibited the direct optical bandgap 3.15 eV. Dye-sensitized solar cells (DSSCs) were fabricated using synthesized ZnO NPs as a semiconducting layer, whichwas dyedwith different low cost dyes such as Eosin B (EB), Eosin Y (EY) and Rhodamine B (RB) that was used to sensitize the photoanode (ZnO NPs).The experimental results showed a significant efficiency for the fabricated DSSCs of synthesized ZnO NPs via sol gel technique comparing to hydrothermal technique. The EY dye exhibited the best performance among others, where a conversion efficiency showed a noteworthy improvement from 0.12 to 1.08 %.

في هذا البحث تم تخليق جسيمات نانوية نقية من أكسيد الزنك باستخدام طريقتي الهيدروثيرمال وطريقة الصول جل. من فحوصات حيود الاشعة السينية تبين أن متوسط حجم الحبيبة تتراوح بين من 25 الي 28 نانومتروتاخذ شكلا كرويا. فحوصات طيف الامتصاص بينت أن العينات جميعها لها اعلي امتصاص في منطقة الاشعة الفوق بنفسجية. وتم حساب فجوة الطاقة للعينات فوجد انها تساوي 3.13 eVو3.16 eVللعينة التي حضرت بطريقة الهيدروثيرمال والصول جل على الترتيب. تم تحضير عينات لخلايا شمسية صبغية وتم استخدام 3 انواع من الاصباغ الكيمياءية كمتحسسات ضوئية. فحوصات الاشعة الفوق بنفسجية بينت ان صبغة الايوزين الاصفر Eosin Yتعطي اعلي امتصاص مقارنة بالاصباغ المستخدمة الاخري. تم رسم منحني الخواص لجميع العينات للخلايا الشمسية المحضرة وتم حساب جميع البارامترات اللازمة لتقييم اداء الخلية. العينة المصبوغةبصبغةEosin Y اعطت اعلي كفاءةJsc = 4.25 (mA/cm2)،Voc = 0.51 V and η=1.08 %

Listing 1 - 4 of 4
Sort by
Narrow your search

Resource type

article (4)


Language

English (4)


Year
From To Submit

2019 (1)

2018 (1)

2016 (1)

2015 (1)