The analytical sensor performance metrics for biomolecular interactions are dependent on the charge-screening effects of the buffer at the electrode/solution interface. High ionic nature of buffers may reduce sensitivity due to increased charge-screening. Typically, for biosensing using non-faradaic electrochemical systems, charge-screening needs to be avoided at the electrode/solution interface for reliable detection of affinity based biomolecular detection. Room temperature ionic liquids (RTIL) consist of charged moieties that form compact electrical double layer (EDL) around the capture probe antibody in an affinity based immunoassay, providing enhanced stability. Further, RTIL moieties also provide nano-confinement of the biomolecular capture probes, thus, enhancing the sensitivity in detection of target analyte. However, the biosensor performance metrics may vary upon interaction with various biological buffers such as serum, saliva, sweat. In this work, we investigated the impact on biosensor metrics due to interaction between RTIL moieties and biological buffers (serum, saliva and sweat). Zeta potential measurements were used to characterize the interaction between capture probe in RTIL and complex biological buffers. The surface charge properties of biomolecules using zeta potential measurements indicated no-charge screening effects of the biomolecules in the presence of RTIL moieties with serum, saliva and sweat buffer. This is primarily due to the formation of compact EDL around the biomolecular capture probe. This property was used to leverage a highly sensitive affinity based biosensor for the detection of interleukin-6 in human serum, saliva and sweat on a nanoporous membrane using non-faradaic electrochemical impedance spectroscopy.