# Simple HPLC-PDA Analysis to Determine Illegal Synthetic Dyes in Herbal Medicines
## 3 Results and Discussion
### Confirmation by LC-MS/MS Analysis
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Colorants** & \begin{tabular}{c} **Precursor Ion** \\ **(\(m/z\))** \\ \end{tabular} & \begin{tabular}{c} **Product Ion** \\ **(\(m/z\))** \\ \end{tabular} & \
\begin{tabular}{c} **Polarity** \\ **(\(m/z\))** \\ \end{tabular} &
\begin{tabular}{c} **Collison** \\ **Energy (V)** \\ \end{tabular} & **References** \\ \hline \multirow{4}{*}{Tartrazine} & \multirow{2}{*}{467.1} & Target ion & 198.0 & - & 18 & \\ \cline{2-6}  & & Ref. ion 1 & 171.9 & - & 21 & [5, 18, 27] \\ \cline{2-6}  & & Ref. ion 2 & 422.9 & - & 12 & \\ \hline \multirow{4}{*}{Auramine O} & \multirow{2}{*}{268.0} & Target ion & 147.1 & + & \(-\)29 & \\ \cline{2-6}  & & Ref. ion 1 & 131.0 & + & \(-\)50 & [5, 28] \\ \cline{2-6}  & & Ref. ion 2 & 252.1 & + & \(-\)34 & \\ \hline \multirow{4}{*}{Metanil yellow} & \multirow{2}{*}{352.2} & Target ion & 156.0 & - & 30 & \\ \cline{2-6}  & & Ref. ion 1 & 79.9 & - & 45 & [19] \\ \cline{2-6}  & & Ref. ion 2 & 287.9 & - & 20 & \\ \hline \multirow{4}{*}{Amaranth} & \multirow{2}{*}{537.0} & Target ion & 316.8 & - & 31 & \\ \cline{2-6}  & & Ref. ion 1 & 236.9 & - & 43 & [18, 27] \\ \cline{2-6}  & & Ref. ion 2 & 194.0 & - & 52 & \\ \hline \multirow{4}{*}{New Coccine} & \multirow{2}{*}{268.3} & Target ion & 206.1 & - & 13 & \\ \cline{2-6}  & & Ref. ion 1 & 79.9 & - & 32 & [5, 18] \\ \cline{2-6}  & & Ref. ion 2 & 220.9 & - & 21 & \\ \hline \multirow{4}{*}{Sunset yellow} & \multirow{4}{*}{203.4} & Target ion & 171.0 & - & 15 & \\ \cline{2-6}  & & Ref. ion 1 & 181.1 & - & 21 & [5, 18, 27] \\ \cline{2-6}  & & Ref. ion 2 & 114.0 & - & 30 & \\ \hline \multirow{4}{*}{Erythrosin B} & \multirow{4}{*}{834.5} & Target ion & 662.7 & - & 34 & \\ \cline{2-6}  & & Ref. ion 1 & 536.8 & - & 33 & [18, 27] \\ \cline{2-6}  & & Ref. ion 2 & 127.0 & - & 55 & \\ \hline \multirow{4}{*}{Azorubine} & \multirow{4}{*}{456.9} & Target ion & 377.0 & - & 20 & \\ \cline{2-6}  & & Ref. ion 1 & 220.9 & - & 32 & [5] \\ \cline{2-6}  & & Ref. ion 2 & 170.0 & - & 43 & \\ \hline \multirow{4}{*}{Acid red 73} & \multirow{4}{*}{255.0} & Target ion & 150.5 & - & 10 & \\ \cline{2-6}  & & Ref. ion 1 & 136.5 & - & 21 & [5, 19] \\ \cline{2-6}  & & Ref. ion 2 & 236.9 & - & 15 & \\ \hline \multirow{4}{*}{Orange II} & \multirow{4}{*}{327.0} & Target ion & 170.9 & - & 23 & \\ \cline{2-6}  & & Ref. ion 1 & 156.0 & - & 31 & [18, 19] \\ \cline{1-1} \cline{2-6}  & & Ref. ion 2 & 107.1 & - & 40 & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: MRM conditions of the LC-MS/MS to identify ten synthetic dyes in herbal medicines. [PERSON] et al. [5] developed a hybrid quadrupole-Orbitrap high-resolution mass spectrometry (HR-MS) method to detect 21 synthetic dyes in herbal medicines. They emphasized that, when they investigated 54 herbal medicine batch samples, herbal medicine samples such as Schisandra fruit (_Schisandra chinensis_), Safflower (_Carthanus tinctrius_), Rhubarb (_Rheum officinal_ Baillon), and Salvia Militorrhizza root (_Salvia militorhiza_ Bunge) contained Azorubine, Auramine O, and Acid orange 7. In general, LC-MS/MS techniques are considered more sensitive and selective analysis procedures than HPLC analysis. Considering the economic situation of the herbal medicine industry in Korea, this study focused on developing an HPLC analysis as a more economical and accessible analysis procedure for quantifying ten synthetic dyes in herbal medicines. Figure 4: Total ion chromatography of LC-MS/MS for ten synthetic dyes extracted by the MRM conditions in the mixed standard synthetic dye solution: Tartrazine, \(m/\)z 467.1 \(>\) 198.0; Auramine O, \(m/\)z 268.0 \(>\) 147.1; Metanil yellow, \(m/\)z 352.2 \(>\) 1560; Amaranth, \(m/\)z 537 \(>\) 3120; New Coccine, \(m/\)z 398 \(>\) 120; Sunset yellow, \(m/\)z 398 \(>\) 120; Erythrosine, \(m/\)z 398 \(>\) 120; Azorubin, \(m/\)z 398 \(>\) 120; Acid red 73, \(m/\)z 398 \(>\) 120, and Orange II. \(m/\)z 398 \(>\) 120.