Real-Time Detection and Analysis of Biomolecular Interactions in Crowded environment using Nanopipette*

Biomolecular interactions play a crucial role in various cellular communication and physiological pathways. Understanding these interactions in the native environment is essential for the development of novel therapeutic strategies for numerous diseases. However, the study of biomolecular interactions is challenging and lacks appropriate tools. In this talk, I will introduce a low-cost, and label-free based detection technique, for real-time detection and analysis of biomolecular interactions in a crowded environment. This innovative approach involves the jamming of biomolecules with the strategic combination of hard confinement via a long taper funnel-shaped tip of a quartz nanopipette tip at the cis side and soft confinement facilitated by hydrogel at the trans side. Notably, the degree of biomolecular crowding can be monitored based on the direction of the ionic current signal. Moreover, upon the co-localization of the ligand with the receptor within the nanoconfinement, the complexes formed at the single molecule level can be detected individually at the nanopore outlet as an ionic current signal. By modulating the level of crowding, the interaction between biomolecules and the percentages of complex formation can also be modulated. The coupling strength between biomolecules is reflected in time-dependent ionic current recordings. This detection strategy has several advantages over traditional ensemble methods and can sensitively detect interactions in small molecules (≤1 kDa) in a crowded environment. Therefore, this methodology holds the promise to revolutionize the study of biomolecular interactions in real-time and utilize them to screen for new drug candidates.