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J Pharmacol Ther Res 2017 Volume 1 Issue 2
November 02-03, 2017 Chicago, USA
4
th
International Congress on
International Conference and Exhibition on
Drug Discovery, Designing and Development
Biochemistry, Molecular Biology: R&D
&
The study on the effect of non-enzymatic glycation on the interaction of human serum albumin and
sodium-fluorescein, via spectroscopic analyses
Priyankar Sen, Sadaf Fatima, Tamanna Anwar, Nabeel Ahmad
and
Asimul Islam
VIT University, India
T
he binding of SF to Human Serum Albumin (HSA) has
been predicted by molecular docking and investigated by
circular dichroism (CD) and fluorescence spectroscopy with
or without glycation at temperatures 296K, 301K, and 310K.
The binding parameters were calculated by quenching of
emission spectrum of a constant concentration of SF (2 μM)
at 513 nm against increasing concentrations of glycated or
unmodified HSA as quencher starting from stochiometry ratio
of 1:1. Sodium Fluorescein (SF) is a fluorescent tracer dye used
extensively in diagnostic tools in the field of Ophthalmology,
particularly in intravenous fluorescein angiography (IVFA). The
HSA-SF interaction found to be a static binding. The Stern-
Volmer constants (Ksv) were in the range of ~104 M-1 and
other thermodynamic parameters like enthalpy (ΔH0), free
energy (ΔG0) and entropy (ΔS0) are like albumin ligand bindings
reported by previous workers. The interactions were found
to be spontaneous, irrespective of temperature or glycation.
Glycated HSA is clinically used to monitor unstable glycemic
controls in diabetic patients. 39% increase in binding affinity
(log K) and free energy (ΔG0) is reported on glycation at 310 K
(room temperature), which may be important in the SF based
angiographies. Further, on glycation HSA-SF binding seems to
change from an enthalpy-driven to an entropy-driven reaction.
SF shows best binding to FA binding site III of HSA, which also
overlaps with drug binding site II of sub domain IIIA. Leu-430
seems to play a pivotal role in the interaction. This is the first
report of glycated HSA and SF binding and comparison between
the thermodynamic parameters of the bindings in the absence
and presence of glycation at different temperatures.
Speaker Biography
Priyankar Sen is working in the field of protein folding and protein ligand interactions
for the enhanced understanding of the molecular behavior of proteins, specifically
albumins. He has done his PhD from Rizwan Khan’s Lab in IBU, Aligarh Muslim
University, India and Post-doctorate from Salunke’s Lab, NII, New Delhi. Out of 5 years’
Doctoral and 8 years Post-doctoral research, he has published 21 papers in international
peer reviewed journals. He is currently working as Assistant Professor in VIT University.
Currently, he is focusing on expression and modification of therapeutically important
proteins and further scale up in bioreactors.
e:
priyankar.sen@vit.ac.in