Table. 4d. (d). Robustness – change in column temperature.
| System suitability | Compound | Change in column temperature | |||||
|---|---|---|---|---|---|---|---|
| (A) Normal condition | (B) 30°C | (C) 40°C | |||||
| Mean (n = 6) | RSD (%) | Mean (n = 6) | RSD (%) | Mean (n = 6) | RSD (%) | ||
| Retention time, tR(minutes) | QUE | 3.956 | 0.031 | 4.063 | 0.074 | 3.861 | 0.162 |
| BDMC | 13.673 | 0.070 | 14.647 | 0.172 | 12.810 | 0.268 | |
| DMC | 15.037 | 0.064 | 15.980 | 0.153 | 14.167 | 0.236 | |
| CUR | 16.502 | 0.064 | 17.423 | 0.143 | 15.657 | 0.196 | |
| Peak area | QUE | 7628483 | 0.252 | 7620525 | 0.254 | 7633341 | 0.259 |
| BDMC | 196493 | 0.261 | 202870 | 0.253 | 172397 | 0.136 | |
| DMC | 1091099 | 0.300 | 1124567 | 0.281 | 1058404 | 0.205 | |
| CUR | 3738544 | 0.244 | 3836306 | 0.285 | 3643910 | 0.196 | |
| Resolution, R | QUE | - | - | - | - | - | - |
| BDMC | 31.946 | 1.437 | 32.560 | 0.233 | 31.471 | 0.267 | |
| DMC | 2.872 | 1.359 | 2.698 | 0.334 | 3.155 | 0.481 | |
| CUR | 2.829 | 0.575 | 2.718 | 0.305 | 3.106 | 0.559 | |
| Tailing factor, Tf | QUE | 1.343 | 0.056 | 1.329 | 0.267 | 1.351 | 0.124 |
| BDMC | 1.551 | 0.421 | 1.233 | 0.525 | 1.089 | 0.077 | |
| DMC | 1.186 | 0.241 | 1.098 | 0.268 | 1.491 | 1.051 | |
| CUR | 1.097 | 0.082 | 1.094 | 0.107 | 1.098 | 0.129 | |
| Theoretical plate, N | QUE | 8734.237 | 0.300 | 8837.810 | 0.448 | 8619.473 | 0.295 |
| BDMC | 15779.175 | 0.595 | 15065.104 | 0.600 | 16276.545 | 1.203 | |
| DMC | 13866.206 | 1.175 | 15742.765 | 0.475 | 15286.704 | 0.311 | |
| CUR | 15846.706 | 0.791 | 15917.987 | 0.394 | 15793.349 | 0.183 | |
| Capacity factor, k’ | QUE | 0.698 | 1.598 | 0.717 | 1.945 | 0.616 | 0.692 |
| BDMC | 4.855 | 0.115 | 5.190 | 0.989 | 4.366 | 0.214 | |
| DMC | 5.449 | 0.349 | 5.752 | 0.966 | 4.962 | 1.315 | |
| CUR | 6.058 | 0.201 | 6.362 | 0.942 | 5.581 | 1.015 | |
The normal conditions of HPLC are a mobile phase of acetonitrile: 2% acetic acid (pH 2.60) = 40% : 60 % v/v, flow rate 1.3 mL/min at UV wavelength of 370 nm and column temperature at 35°C. RSD, relative standard deviation; QUE, quercetin; BDMC, bisdemethoxycurcumin; DMC, demethoxycurcumin; CUR, curcumin.