Table 3 Comparison between this method and conventional methods.
Method | Advantage | Disadvantage | LOD (µg/ml) | Price ($) | Ref |
|---|---|---|---|---|---|
HPLC | High accuracy and reproducibility | Expensive and sophisticated instruments | ~ 0.01 | > 20,000 | |
Time consuming | |||||
Derivatization required | |||||
Cysteine assay kits | Simple and sensitive | Storage at − 20 °C | 1.2 | ≥ 530 | |
Expensive enzymes required | |||||
Limited expiration | |||||
Sodium nitroprusside test | Simple and fast | Imperfect in accuracy | 75 | 200 | |
Depend on cystine solubility | |||||
Do not distinguish cystine from soluble thiol drug-cysteine complexes | |||||
This method | Simple, fast and sensitive | UV light required | 3.6 | ≤ 20 | – |
