Silica nanoparticle‐modified microcomb electrode for voltammetry detection of osteopontin with high sensitivity

Abstract

Osteosarcoma is a commonly occurring bone malignancy, and it is the second most common cause of cancer deaths in adolescents and children. A sensitive silica nanoparticle (Si‐NP) modified current‐volt sensor was introduced to identify the osteopontin antigen, a well‐known biomarker for osteosarcoma. Si‐NP was extracted from the rice husk ash and utilized for the surface functionalization on the interdigitated microelectrode sensing surface. Extracted Si‐NP has a spherical shape with uniform distribution, and it is confirmed by field emission scanning electron microscopy and field‐emission transmission electron microscopy. Si‐NP was layered on the electrode surface through a (3‐aminopropyl)triethoxysilane amine linker, and the antibody was immobilized on Si‐NP through a glutaraldehyde linker. Osteopontin was effectively detected on the antibody‐attached surface, and the determination limit was 0.6 ng/mL. The regression was determined as y = 0.9366x − 1.1113 and the R2 value was 0.9331 and the detection limit of osteopontin was 0.6 ng/mL in the range between 0.3 and 5 ng/mL. In addition, control performance with nonimmune antibodies and albumin did not change the current volt, showing the specific osteopontin identification. This research work brings out the easy and cost‐effective method to diagnose osteosarcoma and its etiology.