Electrochemical biosensor (OBSense) to detect childhood obesity: an in-vitro exploratory study

Childhood obesity is a global public health emergency with an increasing prevalence, and in which traditional anthropometric measurements are not entirely effective in predicting obesity-related comorbidities. Adiponectin is a protein whose levels decrease in serum and saliva during obesity, making it a potential biomarker for childhood obesity providing a better understanding of metabolic dysfunction. Saliva has emerged as a non invasive sampling tool for biomarker detection, making it particularly suitable for use in children. Screen-printed electrodes are disposable and portable electrochemical biosensors with high sensitivity, fast response time, and minimal sample volume requirements. This study presented an electrochemical biosensor for detecting adiponectin, a biomarker associated with childhood obesity, in artificial saliva, serum, and adipocyte supernatant. Gold screen-printed electrodes were functionalized with an anti-adiponectin antibody and evaluated using electrochemical impedance spectroscopy and cyclic voltammetry. The immobilization of the antibody on the gold electrode and its interaction with the protein were confirmed by scanning electron microscopy with energydispersive spectroscopy and confocal microscopy. The biosensor demonstrated a wide range of responses to artificial saliva (50 pg/mL–20 ng/mL) and serum (0.5 μg/mL–12 μg/mL). Additionally, the biosensor was evaluated using mature adipocyte supernatant from differentiated human preadipocytes, with accurate concentration prediction. A blind test using artificial saliva was also performed, validating the success of the electrochemical biosensor. Finally, a machine learning model was developed using electrochemical data to predict the risk levels of childhood obesity. These results suggested that the developed biosensor is consistent and suitable for future practical applications.