محسن محرابی

In this work, the optical properties of Rhodamine B (RdB) are investigated in the attendance of various redblood cells (RBCs). RdB fluorophores, as biological markers, is excited using SHG-CW Nd:YAG laser at532 nm. In fact, the addition of biomolecules of interest to the reference fluorophore notably changesthe fluorescence properties of the suspension. Here, laser induced fluorescence (LIF) spectrophotometrybased on Stern-Volmer quenching formalism and field emission scanning electron microscope (FESEM)are employed here. According to the given fluorescence spectra, the spectral shift of emissions as wellas quenching coefficients are assessed subsequently. The Stern-Volmer formalism is used to determinethe quenching coefficients. In fact, RdB + RBCs suspensions contain a plenty of bioconjugates leadingto the signal reduction and notable red shift in RdB fluorescence emissions. Furthermore, it is demon-strated that the positive blood type RBCs exhibit the higher quenching coefficients and the larger redshifts against those of negative blood types. This mainly arises from the nature of specific sugar antigensavailable on the RBC membranes as to N-acetylgalactosamine and galactose attached to the O-antigenterminal would enhance further quenching of the species. Moreover, a significant correlation appearsbetween Stern-Volmer coefficients and the corresponding RBCs. In fact, distinct discrepancy takes placein quenching coefficients in terms various positive/negative blood types to envisage a facile method ofblood typing.