Biomimetic gastric microtissue electrochemical biosensors for ovalbumin detection

An innovative integrated three-dimensional (3D) bioprinted gastric microtissue electrochemical biosensor was developed in this study for the detection of allergen ovalbumin (OVA). In this system, OVA triggers the release of histamine from gastric microtissue, which then undergoes a redox reaction on the electrode surface, leading to an increase in the peak current. Gelatin methacrylate hydrogel serves as a scaffold for the 3D culture of RBL-2H3 and PC-12 cells for partially restoring allergic reactions in the human body in vitro. Furthermore, gold nanoparticle-modified anodized aluminum oxide sieves macromolecular substances and facilitates sensor nano-analysis. Composites of cerium-based organometallic framework, MnO₂, and gold nanoparticles significantly enhanced the sensitivity of the screen-printed carbon electrode. Under optimal experimental conditions, the detection limit for OVA was 0.042 μg/mL, with a linear range of 0.1-10.0 μg/mL. The fabricated sensor demonstrated high sensitivity, reliability, and simplicity, showcasing its broad potential for allergen detection applications.