In Situ pH Modulation for Enhanced Chemical Sensing: Strategies and Applications

pH is one of the key parameters in chemistry and impacts almost all chemical and biological processes. Also, within analytical chemistry and sensing, pH plays a critical role. This review underscores the critical role of pH manipulation in overcoming analytical challenges posed by complex sample matrices and dynamic environmental conditions. It explores the available tools to control pH at a local scale and how those are or can be applied to improve sensor performance. We focus on four key areas where pH modulation has been or could be leveraged to advance chemical sensing capabilities: i) sensing alkalinity and buffer capacity, ii) sample pretreatment, iii) sensing pH dependent analytes and iv) reducing biofouling. We analyze existing strategies, but also try to identify unexplored possibilities which may have potential and can be exploited for sensing. Combining in situ pH modulation with sensors has emerged as a new strategy for solving complex analytical challenges. In this review we explore different strategies to modify the pH close to the sensor interface i) to measure alkalinity and buffer capacity, ii) for sample pretreatment, iii) for sensing pH dependent analytes and iv) to reduce biofouling. image