The effect of dye concentration to the optical properties of fitc-doped silica nanoparticles / Muhd Hisyamuddin Mapiati

FITC-doped silica nanoparticles (NPs) was successfully synthesized via sol-gel
method.' Fluorescein isothiocyanate (FITC) was incorporated on the silica.
nanoparticles using crosslinker agent of 3-aminopropyl-triethoxysilane (APTES)
Based on this method, ethanol, aqueous ammonia, water, tetraethyl orthosilicate
(TEOS) and APTES were served as constant variables while the concentration of
dye was taken as manipulated variable. Six experiment trials were made where the
first sample was used as a control sample with no addition of dye while the
remaining five sample with different 'dye concentration.; The particle
characterization was carried out using X-ray Diffractometer (XRD), Scanning
Electron Microscope (SEM), Energy-dispersive X-ray Spectroscopy (EDS),
Photoluminescence Spectrometer (PLS), Fourier Transform Infrared (FTIR) and
Ultraviolet-visible Spectroscopy (UV-vis). XRD result shows an amorphous
structure with broad band of 22°. SEM confirms the size of particles were within
the range of nanoscale of average size of 81.25 nm. EDS denote the element present
in the nanoparticles which are Si, O, N, C and S. Meanwhile, the PLS analysis
illustrate the optical properties of FITC-doped silica NPs which result in decreasing
fluorescent intensity as dye concentration increased. Finally, FTIR and UV-vis
shows the presence of silica and carbonyl group based on the incorporation of dye