الفهرس 
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Abstract
The essential aim of the present work is to synthesize and characterize In Situ ZnONPs obtained by use of fungi onto cotton fabrics. Hence, extensive experimental work was planned to find out In Situ Deposition of Mycosynthesized ZnONPs onto Cotton Fabrics for Durable Antibacterial Activity.
The production of nanostructured composite fibers is one area where nanotechnology is already having a huge impact within the textile industry. Nano sized particles have a larger surface area per unit mass and hence higher efficiency than bulk materials. Nanotechnology is facilitating technology that deals with nanometer sized items (10-9).
The steps of study were conducted as following cotton fabrics were supplied from Miser El-Mehalla for weaving and spinning company, Egypt. Tested fungi: Pacelomyces variotii was provided from the Regional Center for Mycology and Biotechnology, AL-Azher University, Nasr city, Cairo. The fungus was maintained on potato–dextrose Agar (PDA) slants.
Different fungal species from local food industrial waste were isolated and purified for selection of the highest fungal biomass producers. Paecilomyces variotii was selected according to their highest secretion of enzymes and proteins. In situ preparation of ZnONPs onto cotton fabrics using the selected biomass fungal producers Paecilomyces variotii which disclosed the successful preparation of ZnONPs in both Ex situ and In situ cotton fabrics after treatment with Zn(NO3)2.
In situ Mycosynthesized of ZnONPs using the potent fungal isolate onto cotton fabrics and its characterizations TEM, SEM, EDX, FTIR, XRD, UV Spectrometry, particle size and Zeta potential. The size of the prepared ZnONPs was around 5 – 20 nm with well stabilization as seen from SEM & TEM analysis. UV-Vis spectroscopy the preparation of NPs is routinely monitored through using UV-Vis spectroscopy. Investigation of the functions of the treated cotton Fabrics, Antimicrobial activity, Washing Durability.
The results can be summarized in the following
characterizations of ZnONPs: UV-Vis spectroscopy the maximum absorption peak Observed from ZnONPs was located at wavelength 370 nm, which assigned to the Surface Plasmon resonance of ZnONPs. Therefore, the absorption band affirmed the successful formation of ZnONPs with polydispersed narrow size particles. The effect of Zn(NO3)2 Concentration (0.5 mM – 2.5 mM) on the ZnONPs formation the absorptions increase by increasing the Concentration of Zn (NO3)2 up to 1.0 mM, which indicates the ability of biomass Filtrate to well stabilizing the ZnONPs with spherical narrow sizes at 1.0 mM of Zn (NO3)2 Further increase in Zn (NO3)2 concentrations, the absorption decrease gradually to reach the low value at Concentration 2.5 mM Zn (NO3)2 .
TEM (Transmission electron microscope): ZnONPs were successfully prepared with well dispersed narrow sizes ranged from 5 to 20 nm These results are in agreement with that obtained from UV-Vis Spectroscopy.
Particle size and Zeta Potential ZnONPs were successfully prepared with narrow distributed size ranged from 50 to 70 nm By increasing Zn(NO3)2 concentration up to 1.0 mM, the size of ZnONPs appeared in agglomerates which indicates lower stability due to decrease the affinity of the secreted fungal enzymes at the higher concentrations This accumulation in ZnONPs size is accompanied with lower zeta potential which reported at + 26 eV and – 26 eV revealing the low stability of the formed NPs.
Fourier Transform-Infra Red (FT-IR) spectroscopy: Cotton IR showed a maximum absorption peaks 1500 cm−1 and 3600 cm-1 which are assigned to stretching vibration of C=O and O-H groups, respectively. Comparing to IR spectra of ZnONPs, new spectrum peaks are seen at near 512 cm-1, which, indeed, is the characteristic peak of ZnO absorption band.
The crystalline structure of ZnONPs was characterized by XRD analysis: determined the main sharp peaks at 2θ = 31.5°, 34.6°, 36.4°, 47.4°, 56.5°, 62.8°, 66.1°,67.9° and 68.9°, which are corresponding to crystal planes of ZnO-NPs (100), (002), (101), (102), (110),(103) and (112). These results declared that, the formed ZnONPs are polycrystalline wurtzite structure (Zincite, JCPDS 5-0664).
SEM-EDX (Scanning Electron Microscope ZnONPs were successfully deposited on the surface of the cotton fabrics with homogeneous distribution over the domain area effectively as compared to the blank cotton fabrics which exhibited a soft appearance & EDX analysis manifested the presence of ZnO-NPs as indicated from the chemical compositions of the treated cotton fabrics with about 10% of the total weight %.
Antibacterial activity of ZnONPs: Antibacterial Activity of cotton treated fabrics Inhibition zone (Disc diffusion) the high antibacterial activity of the insitu prepared ZnONPs onto cotton fabrics on gram negative E.coli bacteria than gram positive S.aureus bacteria, furthermore, the antibacterial activity increased with increasing the concentration of Zn(NO3)2 up to 1.0 mM . upon increase in Zn(NO3)2 concentration , the diameter of clear zone decrease which indicating the limited antibacterial activity against both pathogenic E.coli and S.aureus resulting from low affinity of ZnONPs as previously emphasized by UV-Vis.spectroscopy at high Zn(NO3)2 concentration.
Washing durability: the bacterial reduction of the In situ treated cotton fabrics with ZnONPs attained the 98% and 96% for E.coli and S.aureus, respectively, which indicated the powerful bacterial activity cotton fabrics treated ZnONPs against gram negative, Gram positive bacteria. In addition to this, the antibacterial activity of cotton fabrics was significantly affected by the washing cycles. The reduction of bacterial activity decreased gradually by increasing the washing cycles numbers, which attains the 50% after 15 washing cycles. These results confirms the effective route used for in situ preparation of ZnO-NPs onto cotton fabrics, which as antibacterial activity reserved up to 15 washing cycles with more than 50% bacterial reduction activity.