Toward High-Performance in Heavy Metal Detection: Mechanisms and Applications of Amplified Aptasensors

Heavy metals (Pb, Cd, Hg, As) pose severe, persistent threats to ecological integrity and human health. Conventional detection methods are limited by insufficient sensitivity, cumbersome pretreatment, high operational requirements and costs, restricting rapid on-site detection in resource-limited settings. Aptasensors, with high specificity, excellent stability and low cost, have emerged as a promising alternative. To overcome the sensitivity bottleneck for trace/ultra-trace heavy metal detection, this review systematically dissects three mainstream signal amplification strategies for aptasensor-based heavy metal analysis: nanomaterial-enabled, DNAzyme-mediated, and nucleic acid logic circuit-based amplification. Notably, this review covers the application of AI-aptasensor integration for future heavy metal detection. We also summarize current research progress, prevailing challenges, and future optimization directions, aiming to advance practical high-performance aptasensors for real-world heavy metal monitoring.