Advection‐Enhanced Kinetics in Microtiter Plates for Improved Surface Assay Quantitation and Multiplexing Capabilities

Abstract

Surface assays such as ELISA are pervasive in clinics and research and predominantly standardized in microtiter plates (MTP). MTPs provide many advantages but are often detrimental to surface assay efficiency due to inherent mass transport limitations. Microscale flows can overcome these and largely improve assay kinetics. However, the disruptive nature of microfluidics with existing labware and protocols has narrowed its transformative potential. We present WellProbe, a novel microfluidic concept compatible with MTPs. With it, we show that immunoassays become more sensitive at low concentrations (up to 9× signal improvement in 12× less time), richer in information with 3–4 different kinetic conditions, and can be used to estimate kinetic parameters, minimize washing steps and non‐specific binding, and identify compromised results. We further multiplex single‐well assays combining WellProbe's kinetic regions with tailored microarrays. Finally, we demonstrate our system in a context of immunoglobulin subclass evaluation, increasingly regarded as clinically relevant.

Micro-/nanoscale robotics for chemical and biological sensing

“…In this regard, enhancing the dynamic flux as a means of breaking the bottleneck of mass transport is always appealing to physicists and chemists. Numerous efforts in vastly diverse approaches have been proposed to improve the reaction efficiency and overcome the relevant issues in fluids, such as external advection, 71,77 active depletion of the boundary layer, 78 generation of convective flow by electro-thermophoresis, 79 herringbone microstructures, [80][81][82][83] isotachophoresis, 84,85 acoustics induced mixing [86][87][88] and tuning of probe immobilization. 89 However, in these studies, sophisticated engineering of the interface or introduction of an advanced molecular mechanism 90,91 is inevitable, restricting the potential mass production as well as out-of-lab implementations.…”