Acoustofluidic large-scale mixing for enhanced microfluidic immunostaining for tissue diagnostics.
Muaz S Draz1,2, Diego Dupouy2, Martin A M Gijs1
1Laboratory of Microsystems 2, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland. muaz.draz@epfl.ch.
Lab on a Chip
|June 27, 2023
Summary
Acoustic agitation enhances microfluidic immunoassays by improving staining uniformity and reducing reagent use. This method significantly cuts incubation times and reagent concentrations for biomarkers like Her2 and CK.
Area of Science:
- Biomedical Engineering
- Analytical Chemistry
- Cell Biology
Background:
- Microfluidics offers automated, rapid immunoassays but faces challenges with laminar flow and diffusion-limited mass transport.
- Acoustic-based fluidic streaming is an investigated method to enhance microfluidic mixing.
- Optimizing reagent concentration and incubation time is crucial for immunoassay signal and efficiency.
Purpose of the Study:
- To investigate the effect of acoustic agitation on immunostaining uniformity in microfluidic chambers.
- To explore the impact of reduced incubation times and reagent concentrations on immunoassay signals using numerical simulations.
- To demonstrate the practical application of acoustofluidics for biomarker detection in breast cancer cell pellets.
Main Methods:
- Numerical simulations were employed to model fluid dynamics and mass transport.
- Experimental validation was performed using large-size, thin microfluidic chambers.
- Acoustic agitation was applied to enhance mixing and reduce incubation times.
- Immunoassays for Her2 and CK biomarkers were conducted on breast cancer cell pellets.
Main Results:
- Acoustic agitation significantly improved the uniformity of immunostaining in microfluidic chambers.
- Numerical simulations showed that reduced incubation times and reagent concentrations can be viable.
- Acoustofluidic mixing reduced incubation time by 80% and reagent concentration by 66% for Her2 and CK.
- Higher signal-to-background ratios were achieved compared to static incubation methods.
Conclusions:
- Acoustic agitation is a beneficial technique for enhancing microfluidic immunoassays.
- This method allows for substantial reductions in assay time and reagent usage without compromising signal quality.
- Acoustofluidics presents a promising approach for efficient and sensitive biomarker detection in diagnostics.
