Rapid Detection of Tetracycline Residues in Milk Using Colorimetric Sensor Based on Polymethylmethacrylate (PMMA) and Polystyrene (PS) Polymers

(9:1), PMMA-Mecke (9:1), and PMMA-Marquis (9:1) are the best compositions that can detect tetracycline within 10 s. The test results using scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) and infrared spectrophotometer showed that the reagent had entered the PMMA-based indicator strip. The limit of quantification (LOQ) and limit of detection (LOD) were 11.64 ppm and 3.49 ppm, respectively. The indicator strip has high selectivity toward tetracycline and is stable for 60 days at room temperature in a desiccator. The indicator strip detects tetracycline in milk samples with an accuracy of 83.24%-99.66%. The accuracy test results using liquid chromatography-tandem mass spectrometry (LC-MS/MS) also observed. The indicator strip may be appropriate as an initial screening tool for high-level tetracycline contamination; however, its utility is limited for purposes of strict regulatory compliance.