title: Measurement and simulation of tailing zones of a cationic dye in analytical-scale reversed phase chromatography.
abstract: A quantitative physical description of tailing is reported here for analytical-scale reversed phase chromatography with Type B silica. Simulations of experimental chromatograms for a cationic dye, 1,1'-didodecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI) were performed as a function of DiI concentration and flow rate, revealing nonlinear tailing due to a bi-Langmuir adsorption isotherm. The strong site comprises less than 0.1% of the residual silanols, the desorption rate constant of DiI from this type of site is (85 +/- 8 ms)(-1), and the free energy of the silanophilic interaction is 16 kJ/mol, indicating hydrogen bonding or another strong electrostatic interaction.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA. mwirth@email.arizona.edu
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Wirth
authors.forename: Emily A
authors.initials: EA
authors.lastname: Smith
authors.forename: Shyroine R
authors.initials: SR
authors.lastname: Anthony
mesh_terms: D002232:Carbocyanines / Q000737:chemistry*; D002412:Cations; D002853:Chromatography, Liquid / Q000379:methods*; D004396:Coloring Agents / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D002232:Carbocyanines; D002412:Cations; D004396:Coloring Agents; C072024:carbocyanine dye DiIC12(3)