Running buffer preparation
1] Add a certain amount of NaH2PO4•2H2O into ultra-pure water to prepare 50 mM NaH2PO4 stock solutions.
2] Adjust the pH of NaH2PO4 solutions using 1 M NaOH until the desired pH (generally 6~9) was obtained.
3] Add a certain amount of CD selector into the NaH2PO4 solution to obtain the desired CD concentration (generally 0~30 mM).
4] Add a certain amount of organic modifier (MeOH or ACN) (generally 0~20%, vol/vol) into the solutions from Step 3.
5] Transfer 1.5 mL solutions into two 2 mL-vials
6] Degas the buffer before use.
1] Add a certain amount of racemic analytes into 50/50 (vol/vol) methanol/water mixture to form stock solutions of 50 μg•mL-1.
2] Transfer 1.5 mL stock solutions into 2 mL-vials.
3] Degas the analyte solution before use.
1] Flush the capillary using 1 M NaOH solution for 30 min.
2] Flush the capillary using 0.1 NaOH solution for 30 min.
3] Flush the capillary using ultra-pure water for 30 min.
4] Flush the capillary using running buffer for 15 min.
CE enantioseparation operation
1] Put the cartridge with fused-silica capillary on the CE equipment and put the two buffer vials and one analyte vial in the sample trays.
2] Set sample injection by pressure at 0.5 psi for 4 s.
3] Set the separation voltage as 15 kV.
4] Start injection and separation.
5] Collect separation data and stop running.
6] Flush the capillary using 1 M NaOH solution for 4 min.
7] Flush the capillary using ultra-pure water for 4 min.
8] Flush the capillary using running buffer for 4 min
9] Start next run.