B-050 A Versatile Immunoassay Platform for Fast Multiplex Detection of Protein Biomarkers Based on A Novel Magnetic Particle System

Abstract

Abstract Background A major challenge of clinical diagnostic applications in the field of emergency department is the not only fast but also accurate measurement of multiple protein biomarkers with broad dynamic range spectrum. Here, we describe the development of a versatile immunoassay platform, the VEUS (Versatile, Easy, and User-friendly System), with compact size which occupies minimal space. Methods The VEUS is designed to enable fast multiplex detection (i.e., 15∼60 minutes) of target proteins at a concentration with a low limit of detection (i.e., <1 pg/mL) by automation of overall immunoassay processes.The system possesses four core technologies enabling entirely automated rapid diagnostics: (1) novel magnetic particles for enabling multiplexed assay using various length of rod-shaped magnetic particles (RSMPs) with conjugated individual antibodies, (2) RSMP movement controlling (up & down/well to well) for increasing antibody-antigen reaction and washing efficiency, (3) a unique optical module for highly sensitive imaging under large field of view for a whole imaging well, and (4) an artificial intelligence (A.I.) based intrinsic program for fast and accurate fluorescent signal analysis which covers detection and classification of RSMP based on their length, and then measurement of fluorescent signal and conversion to biomarker concentration. We evaluated clinical performance of the VEUS platform to diagnose traumatic brain injury (TBI), an emergency disease, as a proof of concept of the versatile immunoassay platform. Among TBI, mild TBI (mTBI) is prevalent in younger population with high level of physical activities that have been linked to increased rate of incidences. Although mTBI is rarely resulted in death, unidentified by the Computed Tomography (CT) and prolonged mTBI as a stealth pathology, may cause life-long disability. Results We determined the assay cut-off value from critical concentration of GFAP (Glial fibrillary acidic protein) and UCH-L1 (Ubiquitin carboxy-terminal hydrolase L1) as of 24 pg/mL and 138 pg/mL, respectively. The VEUS performance for a TBI clinical test showed 94.38 % sensitivity and 98.99 % specificity with the clinical serum samples of 89 TBI patients and 97 healthy controls within 50 minutes from the multiplexed assay of GFAP and UCH-L1. Conclusions As a versatile immunoassay platform, the VEUS system showed high specificity and sensitivity from the clinical test for the TBI diagnosis. Thus, the VEUS system can contribute to proper treatment for the TBI patients with rapid and accurate clinical results and be also applied for an independent and a precise diagnosis of multiple emergency diseases, such as sepsis, myocardial infraction, heart failure, and stroke which are common in the field of emergency department.