Zinc oxide-gold nanocomposite modification on dielectrode for diagnosing osteosarcoma by dual probes

Abstract

Osteosarcoma is a malignant bone tumor, originating and developing from mesenchymal tissues. Diagnosis of osteosarcoma is generally carried out by tissue biopsy and radiological investigations, which are painful and expensive. Therefore, researchers are focusing on identifying the biomarkers for osteosarcoma diagnosis. Matrix metalloproteinases (MMP) have been proven to be involved in the regulation of various stages of the progression of cancer. In addition, studies have demonstrated the overexpression of MMPs in osteosarcoma patients, in particular, the inhibitors, inducers, and cytokines show the variations in upregulation of MMP-9 activities in osteosarcoma. Quantifying MMP-9 helps to identify the condition of osteosarcoma. This research was focused on identifying MMP-9 on zinc oxide nanoparticle (ZnONP) -modified interdigitated electrodes (IDE) by a sandwich with aptamer and antibody. Aptamer as a capture probe was saturated at 1 µM on ZnONP modified IDE. MMP-9 was detected by sandwich assay with gold nanoparticle (GNP) modified antibodies, which enhanced the biosensor performances and lowered the detection limit to 100 pg/mL on a linear curve range from 100 to 700 pg/mL [y = 0.4932x - 0.3914; R² = 0.9456]. In addition, MMP-9-spiked serum was detected from 100 pg/mL and increased the current responses with increasing MMP-9–700 pg/mL. Further, control performances with complementary aptamer sequence and the relevant proteins (MMP-2 and IL-6) did not show the changes in current significantly, which confirms the specific detection of MMP-9.