Low-Content Quantitation in Entecavir Tablets Using 1064 nm Raman Spectroscopy

Figure 5

Approximate vs. predicted ETV-H concentrations in calibration set samples and validation set samples obtained by the best performance PLS models (baseline correction and the SNV method for data pretreatment in the wave number range of 1350–1700 cm⁻¹). Despite a long mixing process, the homemade tablets still could not obtain a uniform content, so it was impossible to obtain the exact concentration of ETV-H in each tablet. Approximate ETV-H concentration referred to the approximate value of the real ETV-H concentration.