Table 5 Comparison and assessment of proposed and published RP-HPLC methods using RGB (Red, Green and Blue) model and principles of white chemistry for estimation of THH and PIO
Type of RP-HPLC method | Chromatographic condition | RGB model-based assessment | White analytical chemistry-based assessment |
|---|---|---|---|
RP-HPLC method for estimation of THH (15) | The chromatographic analysis of THH was carried out using Kromasil C18 (250 mm, 4.6 mm, 5.0 µm) analytical column and acetonitrile, water and trifluoroacetic acid (60: 1940: 2.0, v/v) as mobile phase B and acetonitrile and trifluoroacetic acid (2000: 2.0, v/v). Acetonitrile was used as diluent. The method generated waste of more than 100 mL | Red model – The validation of method complied for ICH Q2 (R1) guideline Green model – Acetonitrile is class 2 solvent and its PDE limit is 410 ppm. Acetonitrile is toxic solvent and its total analytical hazards value is 28.6. The method generated organic waste of more than 100 mL Blue model – Acetonitrile is costly organic solvent | The proposed method has good validation efficiency but only estimate THH The method cannot be considered as green analytical method The method requires costly organic solvent such as acetonitrile |
RP-HPLC method for estimation of PIO (18) | The RP-HPLC analysis of PIO was carried out using C18 (250 mm, 4.6 mm, 5.0 µm) column as stationary phase and acetonitrile: 10 mM dihydrogen phosphate buffer of pH 6.0 (50:50, v/v) as mobile phase. Acetonitrile was used as diluent and method generated organic waste of more than 100 mL | Red model – The validation of method complied for ICH Q2 (R1) guideline Green model – Acetonitrile is class 2 solvent and its PDE limit is 410 ppm. Acetonitrile is toxic solvent and its total analytical hazards value is 28.6. The method generated organic waste of more than 100 mL Blue model – Acetonitrile is costly organic solvent | The proposed method has good validation efficiency but only estimate PIO The method cannot be considered as green analytical method The method requires costly organic solvent such as acetonitrile |
Proposed RP-HPLC method for simultaneous estimation of THH and PIO | The chromatographic analysis of PIO and THH was carried out using Shim-pack C18 ((250 mm, 4.6 mm, 5.0 µm) analytical column as stationary phase and ethanol/water of pH 3.5 (60:40, v/v) as mobile phase. Ethanol was used as diluent with water. The method generated organic waste of more than 100 mL but consisting of safe organic solvent | Red model – The validation of method complied for ICH Q2 (R1) guideline. The method development includes implementation of AQbD approach Green model – Ethanol is class 3 solvent and its PDE limit more than 5000 ppm. Ethanol is safe solvent and its total analytical hazards value is only 2.6. The method generated organic waste of more than 100 mL Blue model – Ethanol is very economical organic solvent | The proposed method has good validation efficiency and applied for simultaneous estimation of THH and PIO The method can be considered as green analytical method The method requires economical organic solvent such as ethanol |