倪坤仪-分析化学（二）TLC.ppt

文档介绍：26 Separation and identification of SMZ and TMP in positea by thin layer chromatography
Objectives
the preparation of thin layer plate
the application of TLC as a qualitative technique
the calculation method of Rf and resolution
Principle
TLC is a qualitative and quantitative analysis method by first coating the glass board with the sorbent to form a thin layer and then spotting developing ,and paring with the chromatogram of the reference substance. TMP and SMZ are two ingredients of Sinomin C ompositea, because TMP and SMZ have diffirent absorption by silica and different dissolvability in developing solvent, the identification of TMP and SMZ can be performed paring the dark spots on the thin layer plate.
Equipment and Chemicals
Inert carrier: glass
Solid phase: silica GF254
Mobile phase: chloroform–methanol (10:1)
SMZ solution: 20mg/ml methanol solution
TMP solution: 4g/ml methanol solution
Sample solution: proper amount of Sinomin powder is dissolved in 10ml methanol and filtered
CMC-Na solution: %g/ml aqueous solution
1 and 2 are diameter of 2 solute spots
of thin layer plate
Add 30ml CMC-Na solution to a mortar, mix it with 10g silica GF254 and grind.
Spread the slurry to all the plate. Dry it and then activate it at 105C for 30min and then store it in a ator.
.
Procedures
Prepare thin layer plate
spot
develop
calc