Raman enhancement effect of different silver nanoparticles on salbutamol

Salbutamol is a β-adrenergic receptor agonist compound which has been abused as an animal growth promoter to improve carcass lean meat percentage. At present, the detection of salbutamol by SERS mostly uses gold colloid as substrate, which is expensive and has a high detection limit. In this report, Raman enhancement signal of salbutamol was compared with concentrated gold and silver colloids. The results show that the concentrated silver colloid prepared by reducing silver nitrate with hydroxylamine hydrochloride had superior performance. Three silver colloids with different particle sizes were synthesized by the same reducing agent and used as substrates for spectra acquisition of salbutamol to explore the enhancement performance of different silver nanoparticles sizes on salbutamol. The results showed that silver nanoparticles with larger particle sizes were more conducive to the adsorption of salbutamol. Finally, under the optimal conditions (Silver colloid A as enhanced substrate, 0.2 mol/L NaOH aqueous solution as aggregating compound), a better linear relationship between the concentration of salbutamol (ranged from 0.2 to 1 mg/L) and SERS intensity. The linear equation between SERS intensity and salbutamol concentration was C = 0.0023∙I-0.079 (mg/L) with a good linearity (R(2) =0.994) and lower root mean square error (RMSE(c) = 0.022 mg/L), where C (mg/L) was the concentration of salbutamol solution and I was the SERS intensity of salbutamol solution. Validation set correlation coefficient was 0.988 and prediction root mean square error was 0.029 mg/L. This method provides a new idea for further reducing the detection limit of salbutamol. This study is helpful to further develop a simple and low-cost SERS detection method of salbutamol based on silver colloid.