Plasmonic enhancement in molecular fluorescence of natural curcumin dye with silver nanoparticles: Synthesis & biological application

In this study, silver nanoparticles were prepared using the liquid pulse laser ablation technique. The effect of adding curcumin at certain concentrations to silver nanoparticles on the optical and structural properties was inspected by spectroscopic techniques, X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The infrared results and biological activity of silver nanoparticles and curcumin were investigated on two types of bacteria. The results indicated that the increase in curcumin concentration was the reason for the improvement of visual properties. Increasing the surface plasmon resonance intensity for silver nanoparticles resulted in increased formation of nanoparticles and improved fluorescence. The vibrational frequency in the region of 2927 cm-1 belongs to the aromatic C–H group, and this result confirms that curcumin acts as a covering agent. X-ray diffraction studies of silver nanoparticles and a hybrid of silver nanoparticles and curcumin were performed. The X-ray diffraction results of silver nanoparticles were proven that the crystal system is cubic and polycrystalline, and several angles that are completely identical to the international standard cards for silver were recorded. In this thesis we studied the biological application on two types of bacteria (E. coli, Staphylococcus aureus) and the results showed that the highest bacterial inhibition was in the hybrid sample.