[Study on cucurbit[ 7] uril-mediated capillary electrophoresis].
The use of a novel macrocyclic molecule, cucurbit[7] uril (CB[7]), as an additive in capillary electrophoresis (CE) for the separation of several neutral nitrobenzenes is reported. Disodium hydrogen phosphate-hydrochloric acid was used as the buffer solvent with the UV detection at 254 nm. During the running process, CB [7] bore positive charge under the studied pH range (pH 2 - 6.5) and was adsorbed onto the inner wall of fused silica capillary, leading to a reversal of the electroosmotic flow (EOF). The effects of buffer pH and CB [7] concentration on the EOF behavior were investigated. The influences of the CB [7] concentration on electrophoretic behaviors of nitrobenzenes were also studied, and it was found that the selectivity increased with CB[7] concentration. The results showed that CB [7] provided good selectivity for nitrobenzenes and successful separation was obtained under optimum condition (10 mmol/L Na2HPO4 (pH 2.47, adjusted by HCl)-methanol (90 : 10, v/v), containing 5 mmol/L CB[7]). Possible explanation is also proposed.
Wei
Fang
F
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Liu
Simin
S
Xu
Li
L
Wu
Chengtai
C
Feng
Yuqi
Y
D001952:Bridged-Ring Compounds / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D007093:Imidazoles / Q000737:chemistry*; D009578:Nitrobenzenes / Q000302:isolation & purification*; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
D001952:Bridged-Ring Compounds; D007093:Imidazoles; D009578:Nitrobenzenes; C456276:cucurbit(7)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils