Countercurrent Microfluidic Immunoaffinity Platform for Continuous Enrichment and Multiplexed Detection of Neuroinflammatory Biomarkers
Salma Sultan Alshahrani, Maya Saeed Baselim, Faisal Shuayl Alkathiri, Amira Mamdouh Alkhamash, Bushra Mustafa Alsawadi, Saeed Adel Bayoumi, Ohood Awad Asiri, Emad Abdullah Alsaqabi, Saud Abdulaziz Hijazi, Rola Khalid Alfantokh, Rana Abdulmohsen Alotaibi, Tameem Nawar Alkhaldi, Mohammad Al MohainiAbstract
Background:
Neuroinflammation plays a major role in the development of numerous neurological disorders, yet conventional immunoassays are restricted by large sample volume requirements, limited multiplexing capability and insufficient analytical sensitivity.
Objective:
To develop and evaluate a continuous, low-volume and high-performance diagnostic platform for multiplex neuroinflammatory biomarker detection.
Methods:
A countercurrent microfluidic immunoaffinity platform was developed incorporating antibody-functionalised serpentine microchannels, nanocomposite-based electrochemical immunosensors and real-time computational analysis. Antigen–antibody interaction was enhanced by countercurrent laminar flow, while enzymatic redox amplification enabled ultrasensitive electrochemical quantification.
Results:
The system achieved a capture efficiency of 89.2%, representing a 2.3-fold improvement over single-pass flow and an enrichment factor of 18.4 for interleukin-6 in cerebrospinal fluid (CSF). Electrochemical detection reached a limit of detection of 0.05 pg/mL, providing approximately 40-fold higher sensitivity than the enzyme-linked immunosorbent assay (ELISA) with strong linearity (
Conclusion:
This countercurrent microfluidic immunoaffinity platform offers a low-volume, high-sensitivity and clinically feasible method for multiplex neuroinflammatory biomarker detection. Its integration of continuous-flow enrichment with advanced electrochemical sensing positions it as a promising next-generation diagnostic tool for point-of-care neurological assessment.