A Multiwell-Based Detection Platform with Integrated PDMS Concentrators for Rapid Multiplexed Enzymatic Assays

Abstract

We report an integrated system for accelerating assays with concentrators in a standard 12-well plate (ISAAC-12) and demonstrate its versatility for rapid detection of matrix metalloproteinase (MMP)-9 expression in the cell culture supernatant of breast cancer cell line MDA-MB-231 by accelerating the enzymatic reaction and end-point signal intensity via electrokinetic preconcentration. Using direct printing of a conductive ion-permselective polymer on a polydimethylsiloxane (PDMS) channel, the new microfluidic concentrator chip can be built without modifying the underlying substrate. Through this decoupling fabrication strategy, our microfluidic concentrator chip can easily be integrated with a standard multiwell plate, the de facto laboratory standard platform for high-throughput assays, simply by reversible bonding on the bottom of each well. It increases the reaction rate of enzymatic assays by concentrating the enzyme and the reaction product inside each well simultaneously for rapid multiplexed detection.

Recent advances in paper‐based preconcentrators by utilizing ion concentration polarization

“…In this paper, the recent progress of the ICP effect in the preconcentration of microsamples in a paper-based preconcentrator is reviewed, and the basic working principle, applications, and research progress of ICP are introduced. ICP preconcentration is also widely used in microfluidic chips on other substrates, such as PDMS [97,[119][120][121][122][123][124][125][126][127][128], polycarbonate [129], glass [127,[130][131][132][133][134][135], silicon [36,[136][137][138][139], and land hydrogels [140]. In addition, studies have been conducted on ICP preconcentration driven by ion-selective osmotic membrane pressure [141], ICP preconcentration of magnetic nanoparticles and magnets [142], etc.…”

Determination of Critical Dimensions of Microchannels to Ensure the Electrokinetic Biomolecule Preconcentration: Analytical and Numerical Studies

“…The simulation is performed using our well-tested in-house code, which solves the set of coupled Poisson-Nernst–Planck equation and Navier–Stokes equation directly on a two-dimensional domain. ,,− The finite volume method is used for the discretization of eqs – while the nonlinear discretized Poisson–Nernst–Planck equations are solved using the Newton–Raphson method. To resolve the rapid variation of the ion concentration and the electric potential near charged surfaces and the ion-selective membrane, the mesh is extremely refined toward these surfaces.…”

“…Over the past several decades, advances in microelectromechanical systems (MEMS) technology have led to the development of micrototal analysis systems (μTAS) or lab-on-a-chip (LOC) devices for a wide variety of applications in chemistry and biology. − For example, point-of-care (POC) diagnostic technology is one of the thriving fields of μTAS in which noninvasive liquid biopsy devices have been developed to identify diseases from related indicative biomolecules in the bloodstream at the early stage of disease progression. − Compared to their large-scale analysis systems, μTAS has many advantages, including less consumption of samples, a lower cost of material and manufacture, a rapid analytical time, a result with little noise, and so on. However, in most cases of sample analysis, the concentration of samples is often very dilute and drops below the limit of detection (LOD) of analytical devices, which negatively affects the sensitivity and accuracy of the results.…”

Multiphysics analytical and numerical studies of biomolecule preconcentration utilizing ion concentration polarization: a case study of convergent microchannels

“…We only present a quick overview of the numerical framework based on our well-tested in-house code. [41][42][43][44][45][46][47][48][49][50][51][52] The three coupled governing Poisson-Nernst-Planck-Navier-Stokes equations describe the transport of the ion, and the electrophoretic equation describes the movement of charged biomolecules deciphered directly on a two-dimensional domain. The finite volume method was used to discretize the eqn ( 1)-( 9), while the nonlinear discretized Poisson-Nernst-Planck equations were solved using the Newton-Raphson method.…”