Point-of-Care Electroanalytical Technologies for Lithium Carbonate Monitoring in Bipolar Affective Disorders

Lithium (Li), administered as lithium salts such as lithium carbonate (Li2CO3), remains a gold-standard maintenance treatment for bipolar affective disorder (bipolar disorder), but its narrow therapeutic index requires regular monitoring of lithium−ion (Li+) concentrations. This review critically examines electroanalytical strategies for decentralized Li measurement, including conventional electrodes, screen-printed electrodes, wearable platforms, and minimally invasive sampling. Attention is given to ion-selective recognition, manganese (Mn)-spinel intercalation materials, matrix effects, and the evidence supporting saliva, sweat, interstitial fluid, and capillary blood. The available literature supports these matrices as promising adjuncts but not as universal replacements for standardized venous testing. Their clinical use still requires paired matrix validation, control of sampling time and environmental effects, long-term sensor stability studies, and explicit confirmatory testing rules for suspected toxicity. Laser-induced graphene and fused deposition modeling are therefore discussed only as enabling fabrication concepts rather than as established Li-sensing technologies. Finally, the review outlines regulatory, human factor, connectivity, and healthcare integration requirements that must be addressed before wearable or home-use Li devices can support routine care.