Nano-Biotechnology for early detection of harmful algal blooms in coastal waters

Abstract

Harmful algal blooms (HABs) represent a significant and growing threat to marine ecosystems, human health, and coastal economies worldwide. Traditional monitoring and detection methods for HABs, such as microscopy and chromatography, are often time-consuming, labor-intensive, and incapable of providing real-time data needed for early intervention. Nano-biotechnology offers a transformative approach to HAB detection by integrating nanomaterials with biological recognition elements to create highly sensitive, specific, and rapid biosensing systems. This paper explores recent advancements in nano-biotechnological strategies for early HAB detection, including the use of quantum dots, gold nanoparticles, and graphene-based nanocomposites functionalized with aptamers or antibodies targeting key algal toxins like saxitoxin and domoic acid. Literature indicates that such nano-biosensors can achieve low detection limits, high specificity, and potential for miniaturization and field deployment. However, challenges related to sensor stability in marine environments, biofouling, and scalability remain. We identify key limitations in current detection methods and propose a novel biosensing platform integrating cadmium-free quantum dots with aptamer-based recognition for fluorescence detection, deployed via autonomous monitoring systems. The proposed methodology aims to enable real-time, on-site detection of HABs with improved sensitivity and specificity contributing to more effective monitoring, early warning systems, and mitigation strategies to protect coastal resources and communities.