Different Spectrophotometric Methods for Simultaneous Determination of Trelagliptin and Its Acid Degradation Product

Figure 3

Overlay of the zero-order absorption spectra of TRG (5, 10, 20, 30, 40, and 50 µg/mL) (a) and TAD (2.5, 5, 10, 15, 20, and 25 µg/mL) (b), using methanol as a blank.

(a)

(b)