electromagnetic sensor is a reproducible and accurate clinical detection system. The

sensor also exhibits the property of dynamic testing of the coagulation process [38].

Testosterone, a male sex hormone, is linked to high-grade prostate cancer. Low tes­

tosterone levels are linked to high-risk mortality and death by CVD. Monitoring of tes­

tosterone is significant in clinical, biochemical, and sports endocrinology research [39].

Testosterone doping in sports through illegal consumption is a matter of concern.

Magnetic nanoparticles (MNPs), due to their magnetic behavior, have gotten attention in

biomedical diagnosis. They have electrochemical conductivity and the desired physico­

chemical properties for sensing devices. In a study, magnetic iron oxide nanoparticles

were synthesized for the estimation of testosterone. The MNPs were employed to fab­

ricate the screen-printed electrode. The fabricated sensor was used to capture anti-

testosterone antibodies for detecting testosterone. Testosterone sense was confirmed by

cyclic voltammetry, differential pulse voltammetry, and electrical impedance spectro­

scopy (EIS). The proposed sensor showed a LOD of 23.68 ng/mL with a linear range of

50–1,000 ng/mL. The sensor detected testosterone from urine and serum in the presence

of interferants. The authors proposed that the sensor be used in the clinical diagnosis of

testosterone and the sensor fabrication, as shown in Figure 8.5 [40].

8.7.2 Optical Sensors

Optical sensors are used in the biotechnological industry, ecological science, and health

care. Optical sensors are classified into catalytic and affinity-based and are in wider use

than electrochemical or piezoelectric sensors. Surface plasmon resonance sensors are also

optical sensors [41]. Pathogenic bacteria cause infectious diseases leading to life-

threatening conditions. Bacterial counts of less than 10 CFU/mL of blood are not detected

FIGURE 8.5

Illustration of MNPs-modified SPE for the detection of testosterone. Adapted with permission [ 40], Copyright

(2020), Elsevier.

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