| Abstract: | In a pH 3.6-5.0 Hac-NaAc buffer solution, when sodium tanshinon ⅡA silate (STSⅡA) reacts with La(Ⅲ) to form a chelate, the resonance Rayleigh scattering (RRS) intensity can be enhanced greatly and a new RRS spectrum will appear. The maximum RRS peak is located at 306 nm and the RRS intensity is proportional to the concentration of STSⅡA in a certain range. The method is very sensitive and the detection limit for STSⅡA (3σ/K) is 82.12 ng·mL-1. The optimum reaction conditions and the effect of coexisting substances have been investigated. A new, simple and fast method for the determination of STSⅡA based on RRS method is developed. It can be applied to the determination of STSⅡA in the synthesis samples and Nuoxinkang injection. Combined with infrared absorption and NMR spectra, the structure of the chelate and the reasons of RRS enhancement are also discussed. |
