الفهرس 
.NanotechnologyOnly 14 pages are availabe for public view
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Abstract
The present study sheds light on the mportance of zinc oxide nanoparticles which uses in various fields:such as biomedical effects,electrochemistry, catalysis, sensors, biomedicine, pharmaceutics, healthcare, cosmetics, food technology, textile industry, mechanics, optics, electronics, space industry, energy science and optical devices, metal oxide nanoparticles display a very strong and widely applicable impact.
In this respect we prepared zinc oxide nanoparticles from zinc acetate and zinc sulphate by two sol-gel methods , and the results obtained can be summarized in the following points:
- Characterization zinc nanoparticles by:
X-ray diffraction ,
FTIR analysis .
TEM analysis .
The XRD pattern of the as-prepared sample shows that the crystalline phase of ZnO had not been induced. On the other hand, the annealed powdered samples exhibit a long range order of sharp Bragg peaks. The miller indices for each peak have been indexed to the standard hexagonal wurtzite structure of ZnO. The ZnO nanoparticles annealed from 300 to 600°C displayed similar Bragg peak patterns.
The obtained FTIR spectrum showed that, series of absorption peaks in the range from 4000 – 400 cm-1 have been found. The weak peak observed at 3369 cm-1 and 3160 cm-1 corresponds to the O-H stretching vibration of the intramolecular hydrogen bond. The peaks observed at 1520 are doublets and they correspond to the zinc carboxylate C=O symmetric stretching vibration. The absorption peaks around 1386 cm-1 is assigned to the bending vibration of C-H stretching. The sharp peak at " ~ "685 cm-1 is attributed to the Zn-O stretching mode.
TEM analysis showed that the morphology of the ZnO-NPs have grown in a near-hexagonal shape, the image shows that the powder consists of quasi-spherical nanoparticles. The majority of ZnO-NPs measured fell in the range of 30 to 50 nm in diameter with an average size of 40 nm in diameter.
- Antioxidant activity of zinc oxide nanoparticles, there was a concentration dependent increase in antioxidant activity was observed. The data showed that ZnO-NPs were further highlighted by the quenching of DPPH free radicals. The absorbance values for ZnO-NPs (A) ranged from 49.25 to 53.79% and from 58.24 to 59.54% for ZnO-NPs (B) compared to the absorbance values for ascorbic acid which ranged from 95.2 to 95.9%, and the order of effectiveness is as follows: ascorbic acid > ZnO-NPs (B) > ZnO-NPs (A).
- Antimicrobial activity of zinc oxide nanoparticles, data showed that ZnO-NPs (A) and ZnO-NPs (B) have sufficient antimicrobial activity against all the above nine gram (-) , three gram (+) organisms , three fungi and only one of yeast, it inhibited the growth and the growth inhibition is dose dependent. As dose increased the zone of diameter of inhibition also increased.
- Insectidcal activity of zinc oxide nanoparticles, the results obtained demonstrate the insecticidal activity of ZnO nanoparticles where it was directly contacted with the insect under a controlled environment assuming that no factors that interfere with the outcome. The insect feeding on food dipped in ZnO-NPs solution was affected and the number of days that the insect took to complete its lifecycle had a significant difference compared to the control. The effect of ZnO-NPs on larval mortality , pupal mortality , % pupation , pupal weight gm/pupa , adult malformation and number of egg in bite / female, from results we indicated that , ZnO-NPs (B) have more activity than ZnO-NPs (A).
- Effect of zinc oxide nanoparticles on some vegetative parameters of mentha piperita, Data showed that there were an increase in plant height after treatment with zinc sulfate and ZnO-NPs (A) and (B) compared with control. Also , there were an increase in fresh and dry weight for plants. from tabulated data we indicated that foliar spray with ZnO-NPs (A) or (B) at concentration 25 mg/L were more effective on quantitative parameters like fresh weight and dry weight.
- Chemical composition of mentha piperita essential oil. The data showed that the total identified compounds from menthe oil were 24 represent 99.18 % from total mass. The major compounds found in mentha essential oil, were carvone (53.53%) followed by cis-d-dihydrocarveol (9.88%).
- Toxicity of zinc oxide nanoparticles, The study investigated the effect of nano ZnO on adult male Wistar rats by measuring liver function, kidney function , lipid profile , blood sugar level , hematologic analyses and histopathological changes in the liver. The results showed that there was a significant increase as compared to the negative control in all liver and kidney function indices as well as, glucose, cholesterol, low-density cholesterol and triglycerides levels , while the high-density cholesterol decreased comparing to the negative control. As for the percentage of hemoglobin, red and white blood cells, and platelets, there was no significant difference as compared to the negative control, On the other side the histopathological features of the liver. showed preserved hepatic lobular architecture and intact hepatocytes for negative control, group treated with ZnO-NPs (A) at concentration of 150 mg/kg diet showed distorted lobular architecture in the form of compressed sinusoids and marked hydropic degeneration of hepatocytes. Meanwhile group treated with ZnO-NPs (A) at concentration 300 mg/kg diet showed distorted lobular architecture with markedly degenerated hepatocytes showing focal scattered apoptotic figures and dilated congested sinusoids. group treated with ZnO-NPs (B) at concentration 150 mg/kg diet showed distorted lobular architecture with hydropic degeneration of hepatocytes , while group treated with ZnO-NPs (B) at concentration 300 mg/kg diet showed focal porto-portal and porto-central fibrosis.