Laser-induced graphene (LIG) is a highly promising preparation material for electrochemical sensors; however, its preparation speed and nanomaterial modification steps significantly limit its mass production. Herein, this study proposed a new laser printing strategy that considerably improved the preparation speed of LIG with excellent electrochemical performance. Using the optimal parameters (laser power of 1%, scribing spacing of 0.12 mm, and scribing speed of 100 mm·s⁻¹), it took only 14.2 s to complete the preparation of the detection electrode. Thus, we successfully detected Cd²⁺ and Pb²⁺ without any toxic reagents or electrode modification steps. The limits of detection of the sensor were 0.914 and 0.916 μg·L⁻¹ for Cd²⁺ and Pb²⁺, respectively, which are significantly lower than the required values for drinking-water quality, according to the World Health Organization guidelines. This study provides a novel approach for the rapid detection of heavy-metal ions.

Inosine monophosphate (IMP), as a critical umami substance, is one of the most important indicators for evaluating the quality of meat products. Here, a sensitive electrochemiluminescence (ECL) biosensor based on graphdiyne (GDY)/AuNPs/luminol nanocomposites was constructed to detect IMP. The GDY/AuNPs/luminol nanocomposites were synthesized by using simple one-pot method. GDY utilized its 2D framework to disperse and fix gold nanoparticles, which inhibited the agglomeration of gold nanoparticles and greatly improved its stability and catalytic properties. Importantly, GDY/AuNPs/luminol nanocomposites showed excellent catalytic ability and superior ECL activity towards luminol-H₂O₂ systems due to the synergistic effect of GDY and AuNPs. Under optimal conditions, the prepared biosensor exhibited a wide linear range from 0.01 g/L to 20 g/L, a satisfactory limit detection of 0.0013 g/L, as well as an excellent specificity. Moreover, we carried out the precise analysis of IMP in actual meat samples with acceptable results compared to the liquid chromatography. We believe that this work could offer an efficient ECL platform for accurate and reliable report of IMP levels, which is significant for maintaining food quality and safety.