Synergistic CRISPR-Cas and Nanozyme-Based Fluorescent Sensors for Ultrasensitive Heavy Metal Detection

Heavy metal pollution poses a serious threat to ecological balance and human health. Traditional detection methods, such as atomic absorption spectrometry and inductively coupled plasma mass spectrometry, suffer from complex procedures, high costs and susceptibility to interference, making them unable to meet the requirements of on-site rapid detection. To address this bottleneck, this review focuses on the innovative solution of the synergistic detection strategy combining nanozymes and the CRISPR-Cas systems. The core advantages of this strategy are as follows: it leverages the excellent specific recognition and signal amplification capabilities of the CRISPR-Cas system to achieve a precise response to heavy metal trigger signals; meanwhile, it utilizes the high stability and enzyme-mimicking catalytic activity of nanozymes to convert signals into readable outputs, thereby constructing an efficient detection platform. We elaborate on how this synergistic mechanism enables high-sensitivity detection without sample pretreatment and remarkably improves analytical performance, with a wider linear range and a lower detection limit. Numerous studies have demonstrated that this combined strategy lays a solid foundation for developing portable, high-sensitivity heavy metal detection devices suitable for complex matrices such as food, water and blood samples, holding great promise for field on-site detection applications.