Rapid and simple detection of pethidine hydrochloride injection using surface-enhanced Raman spectroscopy based on silver aggregates

Abstract

A portable Raman spectrometer was used for the rapid detection using surface-enhanced Raman spectroscopy (SERS) of pethidine hydrochloride injection by employing a silver colloid as the SERS active substrate. Different substrates and aggregation agents were investigated in order to explore the optimum conditions for the SERS detection of pethidine hydrochloride injection. Under the optimum experimental conditions, excellent reproducibility and stability of SERS detection was guaranteed. In addition, the limit of detection (LOD) for pethidine hydrochloride injection in water was low at 0.1 μg mL⁻¹ with an analytical enhancement factor of 5.3 × 10⁴, which is extremely far below typical administered dosages (50 mg mL⁻¹). Finally, a good linear relationship between the Raman intensity and concentration was obtained for pethidine hydrochloride injection in water at a concentration range from 0.1 to 10 μg mL⁻¹ (R² = 0.999), which lays a favourable foundation for the semi-quantitative analysis of the concentration of pethidine hydrochloride injection. In general, the capabilities reported here demonstrate that the SERS method is convenient, rapid and efficient, and has good potential in clinical applications for point-of-care detection and real-time monitoring.