Nanomaterial-based sensors and biosensors for enhanced inorganic arsenic detection: A functional perspective

Due to the great importance of inorganic arsenic detection for global environment and human health, many methods and techniques have been developed in the past decades for its quantification in various matrices. Among them, nanomaterial-based sensors and biosensors have been attracting growing attention because, on the one hand, nanostructured materials enable researchers to explore new principles for inorganic arsenic detection, and on the other hand, they can greatly improve the analytical performance. In this review, we summarize recent inorganic arsenic sensors and biosensors dependent on nanomaterials, to inspire materials scientists to contribute more emerging materials and analytical chemists to explore novel sensing methods for this field. In detail, there are five main types of nanomaterial-based principles and strategies explored for inorganic arsenic analysis, including redox properties of inorganic arsenic, inhibitions of natural enzymes, anodic stripping voltammetry, recognitions of inorganic arsenic by aptamers, and specific interactions between inorganic arsenic and nanomaterials. Our emphasis is put on unfolding the versatile roles of nanoscale materials in these sensors and biosensors and how they overcome the limitations faced by traditional approaches. Last but not least, current challenges and future development trends of inorganic arsenic determination with the use of nanomaterials are also provided.