1：Experimental Design and Method Selection:

The study involved synthesizing a photonic crystal molecularly imprinted polymer (PCMIP) sensor for sulfaguanidine detection. The method selection was based on molecular imprinting and photonic crystal technology to achieve optical response without additional instruments.

2：Sample Selection and Data Sources:

Samples included lake water from Jimei Lake and bass fish purchased from a local supermarket in Xiamen, China. Data sources were the reflection spectra measured using a fiber optic spectrometer.

3：List of Experimental Equipment and Materials:

Equipment included a MAX2000-Pro fiber optic spectrometer, UV-Vis spectrophotometer, MDS-10 Microwave Digestion System, JEM-2100 SEM microscope, pH 510 meter, and incubator. Materials included sulfaguanidine, sulfadiazine, sulfadimethoxine, azobisisobutyronitrile, tetraethoxysilane, ethylene glycol dimethacrylate, methacrylic acid, ethanol, methanol, acetic acid, and purified water.

4：Experimental Procedures and Operational Workflow:

Synthesis of SiO2 microspheres using the St?ber method, preparation of PC film via vertical deposition, synthesis of PCMIP by polymerization with template molecules, elution of template, and reflection spectrum measurement after immersion in SG solutions. Real sample detection involved spiking and extraction steps for water and fish samples.

5：Data Analysis Methods:

Data were analyzed using the Bragg equation to relate wavelength shift to SG concentration, with linear regression for calibration. Statistical methods included calculation of LOD (3σ/k) and recovery rates.