Surface functionalized on polystyrene-gold urchin for determining brain injury biomarker

Researchers are focusing on developing materials-aided biosensing strategies and utilizing blood-based biomarkers for traumatic brain injury (TBI) diagnosis. This study aims to develop a highly sensitive method for detecting the TBI biomarker S100β using a gold urchin-mediated ELISA. In this approach, anti-S100β polyclonal antibodies were attached to a polystyrene substrate via gold urchins. S100β was sandwiched between polyclonal and monoclonal antibodies, achieving a limit of detection of 1 pg/mL with an R² value of 0.9419 [y = 0.095x - 0.0206] on the linear curve within the range of 0.001–1000 ng/mL. This method displayed better performance compared to conventional ELISA without gold urchins, which had [y = 0.0857x - 0.0763, R² = 0.9736]. Furthermore, control experiments with γ-aminobutyric acid and glial fibrillary acidic proteins did not increase optical density, confirming the specific detection of S100β. This S100β biosensor has brought a novelty with a unique nanomaterial to enhance the polystyrene surface area and effectively detects low levels of S100β, aiding the diagnosis of brain injury.