Summary:
Traumatic brain injuries (TBI) are typically acquired when a sudden violent event causes damage to the
brain tissue. A high percentage (70–85%) of all TBI patients are suffering from mild TBI (mTBI), which is
often difficult to detect and diagnose with standard imaging tools (MRI, CT scan) due to the absence of
significant lesions and specific symptoms. Recent studies suggest that a screening test based on the
measurement of a protein biomarker panel directly from a patient's blood can facilitate mTBI diagnosis.
Herein, we report a novel prototype system designed as a precursor of a future hand-held point-of-care
(POC) diagnostic device for the simultaneous multi-biomarker sensing, employing a microarray-type
spatially resolved electrochemiluminescence immunoassay (SR-ECLIA). The small tabletop prototype
consists of a screen-printed electrode compartment to conduct multi-analyte ECL sandwich assays, a
potentiostat module and a light collection module, all integrated into a compact 3D-printed housing (18.2
× 16.5 × 5.0 cm), as well as an sCMOS detector. Based on this design concept, further miniaturization,
system integration, performance optimization and clinical evaluation shall pave the way towards the
development of a portable instrument for use at the site of accident and healthcare. To demonstrate the
system's feasibility, current performance and efficiency, the simultaneous detection of three mTBI
biomarkers (GFAP, h-FABP, S100β) in 50% serum was achieved in the upper pg mL−1 range. The proposed
device is amenable to the detection of other biomarker panels and thus could open new medical
diagnostic avenues for sensitive multi-analyte measurements with low-volume biological sample
requirements.