- PROCEDURE
- MAKE: CAMAG
- Preparation of solutions:
- Prepare a standard solution of caffeine in a mixture of methanol and chloroform (4:6 v/v) by diluting 0.1g to 50 ml (Solution A).
- Dilute 5 ml of Solution A to 50 ml with same diluent to get Solution B.
- Injector Linearity:
- Spot in duplicate 5 µl, 10 µl, 15 µl and 20 µl of Solution B on a 20×20 cm Silica gel 60 F254 TLC plate and mark the spotted front.
- Develop the plate over a path of 15 cm in a TLC chamber saturated with a mixture of ammonia, acetone, chloroform and butanol in the ratio of 10:30:30:40 v/v/v/v.
- Once the plate has developed, take out from the TLC chamber and mark the solvent front.
- Allow the plate to dry at room temperature and scan at 254 nm.
- Plot a linearity curve for average area counts versus the spotted volume in µl for scan and calculate the correlation coefficient.
- Acceptance criteria: The correlation coefficient should not be less than 0.98.
- Injector precision:
- Spot 10 µl of solution B, six times on 20×20 cm Silica gel 60 f254 TLC plate.
- Develop the plate over a path of 15 cm in a TLC chamber saturated with a mixture of ammonia, acetone, chloroform and butanol in the ratio of 10:30:30:40 v/v/v/v.
- Once the plate has developed, take out from the TLC chamber and mark the solvent front.
- Allow the plate to dry at room temperature and scan at 254 nm.
- Calculate the %RSD of area counts and Rf values.
- The %RSD should not be more than 2.0.Record the result in the format given as per Format-I.
- Action: If the calibration is not proper then report the results to the departmental head for an appropriate action.
- Frequency: Yearly.
- ANNEXURES:
ANNEXURE NO. | TITLE OF ANNEXURE |
Annexure-I | Calibration of TLC Spotter |
Annexure-I
CALIBRATION OF TLC SPOTTER