Probing aggregation of human insulin in solution using pulsed-field gradient NMR spectroscopy

Abstract

Insulin plays an imporatant role in biological systems and it has been extensively studied as a model of protein structure and function. It’s ability to exist in different forms make its an intereting model therefore it has been extensively studied through circular dichroism(CD) spectroscopy, 1D-1H NMR spectroscopy, dynamic light scat- tering(DLS), mass-spectroscopy etc. The insulin produced and stored in the pancreas is in the active Zn hexamer in which three dimers are surrounded by Zn + ion, but when it released into blood serum by the pH change, this hexamer dissociate into dimer and subsequently monomers which is its physiologically active form. However, monomers is less stable than hexamer exposing it to heat and motion it tend to aggre- gate. In this project, we are trying to study about insulin (with and without EDTA) aggregation at different pH, EDTA, temperature and amount of sucrose.