Surface-Enhanced Raman Spectroscopy for Rapid Determination of β-Agonists in Swine Urine
Abstract Surface-enhanced Raman spectroscopy (SERS) combined with chemometric method was used for the determination of β-agonists including clenbuterol, salbutamol and ractopamine in standard solutions. For standard solutions, the characteristic bands of SERS spectra could be detected at concentrations as low as 2 μg L −1 for clenbuterol and salbutamol, and 0.1 mg L −1 for ractopmiane; while the R 2 of actual values vs. predicted values based on partial least squares (PLS) regression model for the three tested drugs ranged from 0.9134 to 0.9368. For real sample analysis, three β-agonists was artificially added to urine samples (1–20 mg L −1 ) collected from ten different swine, and then a rapid liquid-liquid extraction (LLE) method was used to extract the targets before SERS analyses. Ractopamine in swine urine could be detected at as low as 1 mg L −1 . For quantitative analysis, the R 2 of actual values vs. their values predicted by the PLS models was 0.8810. The LLE method followed by SERS detection took less than 30 min for analysis of β-agonists in swine urine, which indicates the method has the potential for the rapid determination of β-agonists in swine urine with SERS technology.