One-Dimensional Luminous Nanorods Featuring Tunable Persistent Luminescence for Autofluorescence-Free Biosensing

Persistent luminescence nanoparticles (PLNPs), which can remain luminescent after cessation of excitation, have emerged as important materials in biomedicine due to their special ability to eliminate tissue autofluorescence. Even though significant advances have been made in bioimaging, studies on controlled synthesis of PLNPs with tunable properties are lacking. Until now, only a few studies have reported the synthesis of quasi-spherical ZnGa₂O₄:Cr PLNPs, and direct synthesis of PLNPs with other shapes and chemical compositions has not been reported. Herein, we report the direct synthesis of Zn₂GeO₄:Mn (ZGO:Mn) persistent luminescence nanorods (NRs). The length and persistent luminescence of ZGO:Mn NRs can be fine-tuned by simply changing the pH of the hydrothermal reaction system. Moreover, ZGO:Mn NRs exhibit rapid growth rate, and NRs with strong persistent luminescence can be obtained within 30 min of hydrothermal treatment. Aptamer-guided ZGO:Mn bioprobes were further constructed and applied to serum lysozyme analysis. Serum samples from patients with lung cancer, gastric cancer, and colorectal cancer were collected, and the concentrations of lysozyme in these samples were determined. Since the bioprobes displayed long persistent luminescence, serum autofluorescence interference was completely eliminated. The lysozyme quantification results were in good agreement with those obtained using a clinical method, suggesting the good potential of the bioprobes in the analysis of clinical samples. The developed ZGO:Mn NRs possess tunable length and persistent luminescence, and they are ideal for eliminating autofluorescence interference in biosensing, making them valuable in research areas such as studying the functions of biomolecules and monitoring of molecular/cellular networks in their native contexts.