Table 2.
A comparison between existing methods and the proposed method in this paper.
| Instrumental method | Extraction | Clean-up | MDL | Reference |
|---|---|---|---|---|
| HPLC-UV | Aqueous methanol | Anionic SPE | 30 | [6] |
| CE-UV | Aqueous methanol | Anionic and cationic SPE | 150 | [8] |
| HPLC-FLD | Aqueous methanol | Anionic SPE | 6 | [9] |
| HPLC-UV | Aqueous methanol | Anion SPE | 200 | [13] |
| HPLC-MS | Aqueous methanol | Anion SPE | 400 | [13] |
| HPLC-MS/MS | Methanol/acetone | (Extraction with PLE) | 200 | [11] |
| HPLC-UV-MS/MS | Aqueous methanol | Online SPE | 0.3 | [15] |
| HPLC-MS/MS | Aqueous methanol | — | 63 | [10] |
| HPLC-MS/MS | Methanol | — | 9 | This paper |
HPLC: high performance liquid chromatography; UV: ultraviolet detection; CE: capillary electrophoresis; FLD: fluorimetric detection; MS: mass spectrometry; MS/MS: tandem mass spectrometry; SPE: solid phase extraction; PLE: pressure liquid extraction.