Table 2: System suitability data (n=6) of a standard solution containing salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid and 3,4-dihydroxybenzoic acid (5 μg/mL for each component), measured at 247 nm.
| Standards |
tR (min) |
RSD% for tR |
Area |
RSD% for area |
k |
Symm |
| 3,4-DHBA |
3.861 |
2.47 |
343.53 |
7.44 |
1.970 |
0.80 |
| 2,5-DHBA |
6.320 |
2.49 |
152.32 |
9.30 |
3.862 |
0.77 |
| 2,3-DHBA |
8.876 |
0.62 |
120.57 |
4.33 |
5.828 |
0.75 |
| 2,4-DHBA |
9.788 |
1.49 |
277.28 |
7.42 |
6.529 |
0.83 |
| SA |
17.965 |
1.11 |
137.28 |
8.49 |
12.819 |
0.83 |
tR: retention time of compound
RSD%: relative standard deviation (%)
k: retention factor
Symm: symmetry factor
DHBA: dihydroxybenzoic acid; SA: salicyclic acid