Rapid determination of ultra trace amounts of residual protein in penicillin based on its enhancement effects of Rayleigh light scattering on trimethoxyphenlyfluorone (TM-PF)-Mo(VI) complex

This is a report on the ultra trace amount determination of protein in penicillin based on the interaction with trimethoxyphenlyfluorone (TM-PF)-molybdenum (Mo)(VI) complex in the presence of Triton X-100 microemulsion by Rayleigh light scattering (RLS). At pH 2.70, the weak RLS of TM-PF-Mo(VI) complex was enhanced greatly by the addition of proteins. Based on this, the interaction of TM-PF-Mo(VI) complex with proteins was studied and a new quantitative determination method for proteins was developed. This method is extremely sensitive (the linear range of the calibration curve was 0-80 ng mL−1 for bovine serum albumin (BSA). The detection limit was 0.47 ng mL−1), simple, steady and free from interference of coexisting substances. TM-PF-Mo(VI) complex as a spectral probe can be used to the determination of the residual protein in penicillin samples successfully.