Nondestructive Inspection of the Components in the Admixed Injectable Drugs by Raman Spectroscopy

A nondestructive analysis technique using Raman spectroscopy was developed to measure the concentrations of the components of admixed injectable drugs. Taking Gaster® injection as the model injectable drug, several Gaster® saline solutions of clinical doses were prepared and put in plastic saline bottles and polypropylene syringes. The Raman spectra of Gaster® injection had sharp peaks at around 1045 cm−1. These peaks coincided with that of nicotinamide, which was present at a fixed concentration of 50 mg/mL in the solutions. When Gaster® injection was prepared in a quartz cell (to exclude effects due to the plastic bottles and polypropylene syringes), the peak area from 1025 to 1056 cm−1 was well correlated with that of the content of the injection. Further, based on Raman measurements from the surface of the plastic bottles and the polypropylene syringes, there was a linear relationship between the nicotinamide concentration and the peak area from 1025 to 1056 cm−1, that is, in this area there was no overlapping of peaks. These results indicate that Raman spectroscopy can be used for the nondestructive densitometry of the component concentration of an injectable drug after its preparation.