Clinically Deployable Electro-Immunosensing Device Comprising Bioactive Glass-MWCNT for Alkaline Phosphatase Detection in Human Serum Samples

Bone is a dynamic tissue that serves several purposes in the human body, including storing calcium, forming blood cells, and protecting and supporting the body's organs. Alkaline phosphatase (ALP) is secreted into the circulation by osteoblasts, the cells responsible for making bone. It attaches to the surface of osteoblast cells or matrix vesicles. Accordingly, ALP is present in serum and is a popular biomarker for the evaluation of bone disease and other disorders in clinical evaluations. In this study, a composite probe made of bioactive glass (BG) and multiwalled carbon nanotubes (MWCNT) was used to detect ALP through electrochemical impedance spectroscopy (EIS) without the need for labels. By combination of physical methods with electrochemical analysis, the biosensor probe was characterized. The analytical performance of the biosensor was evaluated using EIS, and the results revealed that it has a limit of detection (LOD) of 2.29 ± 0.35 U/L and a linear dynamic range (LDR) of 25-600 U/L; both of which are within the acceptable range for ALP detection in clinics. When tested against serum interfering chemicals, the biosensor probe that was designed shows a strong selectivity for ALP (<i>K</i>_sel < 0.06). In addition, human serum and fetal bovine serum were used to test the system's ability to detect ALP in biological samples.