1：Experimental Design and Method Selection:

The study involved a two-step synthesis process using melamine and 3-aminophenylboronic acid to fabricate g-CNQDs/3APBA. The covalent bonds between g-CNQDs and boronic acid groups were introduced for multi-chemical sensing.

2：Sample Selection and Data Sources:

Bulk g-C3N4 was fabricated from melamine, and g-CNQDs were prepared through chemical oxidation and hydrothermal process.

3：List of Experimental Equipment and Materials:

Materials included melamine, 3-aminophenylboronic acid, and various chemicals for synthesis and characterization. Equipment included FT-IR, HR-TEM, XPS, PL, UV-Vis spectrometers, and confocal laser fluorescence microscope.

4：Experimental Procedures and Operational Workflow:

The synthesis involved acid treatment of g-C3N4, hydrothermal process to produce g-CNQDs, and functionalization with 3APBA. Glucose detection was performed by adding glucose to the g-CNQDs/3APBA solution and measuring PL spectra.

5：Data Analysis Methods:

The PL intensity was analyzed to determine glucose concentration, and selectivity was tested against various interfering species.