An electrophoretic procedure using thin layer plates of silica-gel 60F
254 (Merck) and cellulose gel (Asahi Kasei Co., Ltd., Japan) has been developed for the separation and detection of 7 tetracyclines (TC, CTC, OTC, MTC, DMCTC, DOXY and MINO). Seventeen electrolyte solutions with different pH values were examined. The results obtained were as follows.
1. With the silica-gel plate (10×20cm), fairly good separations of tetracyclines were obtained in 0.2
M sodium phosphate (dibasic)-0.1
M citric acid (20:980), pH=2.2, for 40min at 1, 000V and in 1.0
M sodium carbonate-1.0
M sodium bicarbonate-water (50:50:900), pH=9.8, for 60min at 500V
2. With the cellulose plate (10×20cm), good results were obtained when the electrophoresis was done in pyridine-acetic acid-water (1:11:89), pH=3.6, for 20min at 2, 000V and in 0.05
M succinic acid-0.05
M sodium tetraborate (778:222), pH=4.2, for 40min at 2, 000V.
3. Five tetracyclines (TC, CTC, OTC, DMCTC, MINO) except for MTC and DOXY were separated from each other under the above 4 electrophoretic conditions.
4. All tetracyclines on TLC plates were well detected by UV absorption measurement at 365nm.
View full abstract