A universal array platform for ultrasensitive, high-throughput and microvolume detection of heavy metal, nucleic acid and bacteria based on photonic crystals combined with DNA nanomachine.

The development of a universal, sensitive, and rapid assay platform to achieve detections of heavy metal, nucleic acid and bacteria is of great significance but it also faces a thorny challenge. Herein, a novel and universal array platform was developed by combining photonic crystals (PCs) and DNA nanomachine. The developed array platform integrated the physical and biological signal amplification ability of PCs and DNA nanomachine, resulting in ultrasensitive detections of Hg, DNA, and Shigella sonnei with limits of detection (LODs) of 22.1 ppt, 31.6 fM, and 9 CFU/mL, respectively. More importantly, by utilizing a microplate reader as signal output device, the array achieved high-throughput scanning (96 samples/3 min) with only 2 μL loading sample, which is advantageous for the detection of infectious dangerous targets. In addition, the PCs array could be obtained easily and rapidly based on self-assembly of colloidal nanospheres, and the DNA nanomachine was operated with enzyme-free and time-saving features. Benefiting from these merits, the proposed PCs array offered a powerful universal platform for large-scale detection of various analytes in the fields of pollution monitoring, epidemic control, and public health.