Linearity and dissociative antigen noise analyses of competitive microfluidic heterogeneous immunoadsorption
Siwei Zhao1, Wei Wang, Zhihong Li
1National Key Laboratory of Micro/Nano Fabrication Technology, Institute of Microelectronics, Peking University, Beijing 100871, China.
Insights
Microfluidic heterogeneous immunoadsorption (MHI) shows promise for clinical diagnostics. Diffusion-controlled MHI is recommended for its linear dose-response and perfect assay signals, avoiding antigen noise.
Area of Science:
- Biomedical Engineering
- Analytical Chemistry
- Nanotechnology
Background:
- Microfluidic heterogeneous immunoadsorption (MHI) is a key on-chip sample preparation technique for clinical diagnostics.
- Electroosmosis flow (EOF)-based MHI is effective but requires optimization for saturated adsorption performance.
Purpose of the Study:
- To numerically investigate the adsorption performance of EOF-based MHI under saturated conditions.
- To analyze the influence of different control modes (flow, surface reaction, diffusion) on MHI performance.
Main Methods:
- Numerical simulation of competitive MHI under saturated status.
- Analysis of electroosmosis flow (EOF) dynamics and adsorption kinetics.
- Characterization of MHI performance across various fluidic control modes.
Main Results:
- Saturated EOF-based MHI achieves a linear dose-response and perfect assay signals in surface reaction or diffusion control modes.
- Diffusion control mode effectively eliminates dissociative antigen noise.
- Diffusion-controlled MHI offers tunable assay times and practical flow velocities for chip applications.
Conclusions:
- Diffusion-controlled microfluidic heterogeneous immunoadsorption is optimal for sensitive and reliable clinical diagnostics.
- This method provides a robust platform for on-chip sample preparation, minimizing assay noise and allowing for precise control.
Abstract:
Presently, microfluidic heterogeneous immunoadsorption (MHI) has been regarded as an effective and efficient on-chip sample preparation method for various clinical diagnoses. In this work, adsorption performances of an electroosmosis flow (EOF)-based competitive MHI under saturated status are studied numerically. Along with the well-known flow and surface reaction control modes, the diffusion control mode specified in the fluidic configuration is scrutinized to characterize the MHI performance. The numerical results indicate that only in the surface reaction or the diffusion control mode can saturated EOF-based MHI obtain a linear dose-response along with a perfect assay signal without so-called dissociative antigen noise. Considering the tunable assay time and realizable flow velocity required by chip applications, the diffusion controlled MHI is recommended in this work.
