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in this paper, two novel Composites zinc phosphate/Polyvinyl alcohol (ZnP-PVA) and Zinc Phosphate/Polyvinyl alcohol/Carboxymethyl cellulose (ZnP-PVA/CMC) had been synthesized by a low-temperature and one-step ultrasonic-template assisted route. For characterization of samples, Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Energy Dispersive X-Ray Analysis (EDAX), MIC/MBC and EIS were used. FTIR spectra of the composite confirmed the functional groups present in the composite and PVA/CMC/Zn2+ ions infraction and also SEM and TEM images showed the composites have a layered structure with rectangular microcrystals (2.8 mm width ZnP-PVA was able 100% to completely remove bacteria in the tested sample. As the results show, Anti-corrosion efficiency inhibitor ZnP-PVA is 92.8% at 2 h, 70.6% at 4 h, 68.0% at 24 h and aslo ZnP-PVA/CMC is 67.7% at 2 h, 45.6% at 4 h, 50.5% at 24h, has been investigated.

In This study, three new surface-modified antibacterial and anticorrosive nanocomposites (zinc Phosphate- Polyvinyl Pyrrolidone, Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite and Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite/Alginate) were synthesized in low-temperature by facile and efficient method. We crosslink Alg with Zn2+ and Ca2+ to make it insoluble and enhancing of their physical and biological properties (zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite/Alginate). Nanocrystals were characterized by (XRD), (FT-IR), (EDX), (SEM) and (TEM). the TEM image showed that the core shell nanocrystal had good dispersion with a particle size of 8–36, 12–38 and 10–45 nm, respectively. Antibacterial rate of the Zinc Phosphate- Polyvinyl Pyrrolidone, Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite and Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite/Alginate NPs reached near 100%. To analyze the EIS results obtained from the equivalent circuits, parameters such as Rct, CPEdl, Rf, n, CPEf, and Rt were extracted. Nyquist diagrams demonstrated that the Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite sample had better protection than the Zinc Phosphate- Polyvinyl Pyrrolidone and Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite/Alginate sample, at all immersion time. The phase angle of the Zinc Phosphate- Polyvinyl Pyrrolidone (-θ 11°/96 h) was a greater value compared with the Zinc Phosphate- Alginate sample (-θ 10°/96 h) and Zinc Phosphate- Polyvinyl Pyrrolidone/Hydroxy Apatite/Alginate (-θ 4.2°/96 h), indicating a transition from capacitive to inductive behavior with longer immersion times.

Background and Objectives: Acinetobacter baumannii is one of the main pathogens of the hospital and causes various infections. csu A/BABCDE involved in the initial surface attachment during biofilm formation and bap gene produces specific proteins at the cell surface that play a direct role in formation of biofilm and the infectivity of this bacterium. The aim of this study was to investigate the effect of silver nanoparticles and gold nanoparticles on the expression of bap and csu genes in the Acinetobacter baumannii biofilm formation. Materials and Methods: The susceptibility test was performed to determine the MIC of silver nanoparticles, gold nanoparticles and gold- vancomycin nanoparticles performed by broth dilution method on A. baumannii strains. The ability of biofilms formation in strains treated by MIC of silver nanoparticles and gold- vancomycin nanoparticles were evaluated by microtiter plate method and A. baumannii ATCC19606 used as control. Expression of the csu and bap genes were determinded by measuring the cognate mRNA level by real-time PCR. Results: In present study, gold nanoparticles could not prevent the growth and biofilm formation of A. baumannii strains. The MIC concentration of silver nanoparticles and vancomycin- gold nanoparticles were 6.25 μg/ml and 0.625 μg/ml respectively and MBC concenteration of nanoparticles for 70% of strain was 12.5 μg/ml and 1.25 μg/ml respectively. Real-time PCR and data analysis, determined that the expression of bap, csuC and csuE genes in A. baumannii strains treated with MIC concentration (6.25 μg/ml) of silver nanoparticles decreased compared to control groups. Also, the expression of csuC and csuE genes in strains treated with MIC concentration (0.625 μg/ml) of vancomycin -gold nanoparticles increased, however the expression of bap was decreased compared to the control groups. Conclusion: Due to the inhibitory effect of silver nanoparticles and gold- vancomycin nanoparticles against A. baumannii biofilm formation and genes expression, they can probably be used for prevent of biofilm formation in medical instrument or can be use for treatment of infections with or without antibiotic.