(27at) A Rapid, Fully Automated Modular Electrochemical Platform Based on a Porous Flow-through Electrode for Sensing Biological Molecules of Interest

The Basuray group at NJIT has developed a sensor platform called ESSENCE that uses a Shear-Enhanced, flow-through non-planar 3D Nanoporous Electrode to overcome current electrochemical sensors limitations as a POC sensor, specifically selectivity, and sensitivity limitations. ESSENCE consists of a microfluidic channel packed with a transducer material like carbon nanotubes or other 2D materials. The transducer material is functionalized with capture molecules surrounded by interdigitated electrodes. The porous electrode architecture enhances shear forces leading to high selectivity. The increased convective fluxes disrupt diffusive processes like the electric double layer, leading to rapid measurements. The enhanced electric field penetration due to the 3D electrode leads to a significant increase in signal from target molecule acquisition. A packed channel has a higher Zeta potential than an open channel and significantly reduces the electrical double layer (EDL) length. This moves the EDL relaxation frequency to a higher frequency, allowing sensor data to be taken at considerably higher frequencies than ambient noise. Removing parasitic noises from the double layer and the measurements at high frequency leads to substantial enhancement in the signal-to-noise ratio. These lead to increased signal-to-noise ratio and enhanced sensitivity. In addition, the diffusion limitations are removed due to the high Peclet Number in ESSENCE, allowing rapid measurements. The unique chip architecture allows us to assemble the chip at room temperature (modular, solving cold chain issues). It is worthwhile to note that the transducer material (porous electrode) can be easily exchanged to target different biomolecules, thus making ESSENCE a universal modular platform. For example, different 2D and 3D nanomaterials from graphene oxide, carbon nanotubes, and metal-organic frameworks can be used to tailor the platform to detect biological molecules or chemical moieties. We have optimized the ESSENCE technology to be a modular, automatic, and portable one-stop instrument for regular users to screen for infectious diseases, liquid biopsy, and toxin detection to detect emerging pathogens for early prevention. A small (15 cm x 17cm) USB programable fluidic/oscilloscope base with a 15-minute total detecting protocol is applied to our ESSENCE system for a fast diagnostic. This portable platform can respond to the measurable EIS signals from the oscilloscope with a 25 ul sample size ( DNA and HER2 proteins in undiluted artificial Urine) with a fully automatic process at the µM to low pM concentrations in 15 minutes.