Fluorescence emission quenching of RdB fluorophores in attendance of various blood type RBCs based on Stern-Volmer formalism

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2021-03, Vol.248, p.119237, Article 119237
• Main Authors: Seyedi, S., Parvin, P., Jafargholi, A., Abbasian, A., Mehdinejad, M., Khorrami, A., Mehrabi, M., Moafi, A.
• Format: Article
• Language: English
• Subjects: ABO RBCs; Laser induced fluorescence (LIF); RdB fluorophore; Stern-Volmer equation
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2020.119237

[Display omitted] •The mixture of RdB fluorophore and RBC species are excited at 532 nm to record various LIF spectra.•RdB + RBCs fluorescence emissions of different blood types demonstrate certain values of Stern-Volmer coefficient.•There is a correlation between Stern-Volmer coefficient and corresponding spectral shift for ABO blood group.•Specific sugar on RBCs membrane exhibit key factor for photon path length elongation, reabsorption and corresponding spectral shift. In this work, the optical properties of Rhodamine B (RdB) are investigated in the attendance of various red blood cells (RBCs). RdB fluorophores, as biological markers, is excited using SHG-CW Nd:YAG laser at 532 nm. In fact, the addition of biomolecules of interest to the reference fluorophore notably changes the fluorescence properties of the suspension. Here, laser induced fluorescence (LIF) spectrophotometry based 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 well as quenching coefficients are assessed subsequently. The Stern-Volmer formalism is used to determine the quenching coefficients. In fact, RdB + RBCs suspensions contain a plenty of bioconjugates leading to the signal reduction and notable red shift in RdB fluorescence emissions. Furthermore, it is demonstrated that the positive blood type RBCs exhibit the higher quenching coefficients and the larger red shifts against those of negative blood types. This mainly arises from the nature of specific sugar antigens available on the RBC membranes as to N-acetylgalactosamine and galactose attached to the O-antigen terminal would enhance further quenching of the species. Moreover, a significant correlation appears between Stern-Volmer coefficients and the corresponding RBCs. In fact, distinct discrepancy takes place in quenching coefficients in terms various positive/negative blood types to envisage a facile method of blood typing.