A portable microfluidic photometric detection method based on enzyme linked immunoscatter enhancement

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Point-of-Care Diagnostics

Background:

• Smartphone-based Enzyme-Linked Immunosorbent Assay (ELISA) is promising for point-of-care testing (POCT).
• Smartphone camera limitations hinder accurate detection compared to spectral devices.
• Existing ELISA POCT platforms face challenges in portability and operational complexity.

Purpose of the Study:

• To develop a microfluidic photometric detection method for ELISA that enhances smartphone-based POCT accuracy.
• To improve image acquisition accuracy using a scattering enhancement model for absorbance error compensation.
• To create a portable and user-friendly ELISA POCT platform integrated with smartphones and microfluidic chips.

Main Methods:

• Developed a microfluidic photometric detection chip with optimized optical path and adjustment systems.
• Established an absorbance error compensation model based on scattering enhancement characteristics of IMB (Image Measurement Bóng).
• Designed a smartphone application (App) for POCT detection and data analysis.
• Validated the method using simulated samples and IL-6 (Interleukin-6) spiked samples.

Main Results:

• Achieved a 22.6% increase in the linearity of absorbance and concentration after implementing the absorbance error compensation model.
• Demonstrated a good linear correlation (R² > 0.95459) between detected IL-6 concentration and sample concentration.
• Confirmed that the detection limit and accuracy meet standard requirements for POCT.

Conclusions:

• The proposed microfluidic photometric detection method significantly improves the accuracy of smartphone-based ELISA for POCT.
• The developed platform addresses portability and operational complexity issues of traditional ELISA.
• This work lays the foundation for the widespread adoption of smartphone-integrated ELISA POCT platforms.