EFFECT OF CO-MODIFIERS IN CYCLODEXTRIN-MODIFIED MOBILE PHASES ON THE REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC SEPARATION OF POLYAROMATIC HYDROCARBONS
N. Husain et al., EFFECT OF CO-MODIFIERS IN CYCLODEXTRIN-MODIFIED MOBILE PHASES ON THE REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC SEPARATION OF POLYAROMATIC HYDROCARBONS, Journal of chromatography, 699(1-2), 1995, pp. 73-83
The effect of two co-modifier containing tert.-butyl moieties, tert.-b
utyl (N-hydroxy) carbamate and tert.-butyl carbazate, on the retention
behavior of six polyaromatic hydrocarbons (PAHs) using cyclodextrin-m
odified mobile phases has been examined. Both modifiers resulted in sh
orter retention times for all PAHs, when a size-compatible cyclodextri
n was present in the eluent. This decrease has been attributed to the
formation of a ternary PAH-cyclodextrin-modifier complex. The apparent
formation constants calculated for these complexes are of the order o
f approximately 10(2) M(-1), with the exception of the beta-CD-pyrene
complex, which was determined to have a 2:1 stoichiometry. Mixtures of
beta- and gamma-cyclodextrins were used in the mobile phase along wit
h tert.-butyl carbazate to achieve a baseline separation of all six PA
Hs under 50 min.