Wearable electrochemical microneedle sensing platform for real-time continuous interstitial fluid monitoring of apomorphine: Toward Parkinson management

Abstract

Parkinson’s disease (PD) is a progressive neurodegenerative disorder, impacting millions of people across the globe. For its management, pro-neurotransmitters or agonists are commonly being prescribed, which help to mitigate the symptoms. However, the progressiveness of PD and narrowing down of the drug therapeutic window eventually led to its ineffective management. Therefore, the requirement of continuous monitoring of administered drugs is of utmost need. In view of this, here, we demonstrate a microneedle-based wearable electrochemical sensor platform for the continuous monitoring of apomorphine (APO), a widely used therapeutic drug for Parkinson’s management. The APO sensor relies on a metallized carbon-paste packed hollow microneedle, operated using the square wave voltammetry (SWV) and chronoamperometry (CA) based transduction modes. Under the optimal conditions, the microneedle sensor offers sensitive detection of micromolar APO concentrations in artificial interstitial fluid (ISF) through the monitoring of the two oxidation peaks of the APO catechol and tertiary amine moieties (at 0.1 V and 0.7 V, respectively). The microneedle sensor exhibited a detection limit of 0.6 and 0.75 μM with the transduction techniques SWV and CA, respectively, and good operational stability as well as anti-biofouling protection in artificial-ISF medium. The specificity has been tested for the developed sensor in the presence of potential interfering molecules, where the developed sensor showed the selectivity towards APO. The attractive analytical performance demonstrated in the skin mimic environment makes the new wearable APO microneedle sensor a powerful candidate for continuous APO detection in PD management.