This contributed volume explores the synthesis, characterization, and application of biocompatible nanomaterials for multifunctional sensor technologies, covering detection systems for heavy metal ions, biomolecules, pesticides, and pharmaceutical drugs. It integrates cutting-edge approaches, including AI and IoT, to enhance sensor performance, alongside discussions on green synthesis, real-world applications, commercialization, and scalability. A valuable resource for researchers, engineers, and professionals in nanotechnology, biosensing, environmental monitoring, and healthcare diagnostics, this book bridges fundamental concepts with innovative advancements in sustainable and high-performance sensing solutions.