Development and Validation of a Stability-Indicating RP-HPLC Method for the Simultaneous Estimation of Guaifenesin and Dextromethorphan Impurities in Pharmaceutical Formulations

Figure 5

(a) Linearity graph of Guaifenesin. (b) Linearity graph of Guaifenesin impurity A. (c) Linearity graph of Guaifenesin impurity B. (d) Linearity graph of Guaifenesin impurity C. (e) Linearity graph of Guaifenesin impurity D. (f) Linearity graph of Dextromethorphan. (g) Linearity graph of Dextromethorphan impurity A. (h) Linearity graph of Dextromethorphan impurity B. (i) Linearity graph of Dextromethorphan impurity C. (j) Linearity graph of Dextromethorphan N-oxide. (k) Linearity graph of Dextromethorphan impurity NFM. (l) Linearity graph of Dextromethorphan impurity NFO.

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