Тип публикации: статья из журнала
Год издания: 2020
Идентификатор DOI: 10.1002/elps.202000189
Ключевые слова: capillary electrophoresis, drug delivery, host–, guest complexes, pentacyclic lupane triterpenoids, stability constant, host–guest complexes
Аннотация: The complexation of ester betulin derivatives with (2-hydroxypropyl)-beta-cyclodextrin (HP-beta-CD) was studied by mobility shift affinity CE. Electrophoretic mobility for triangular peaks was calculated using the parameter a(1) of the Haarhoff-Van der Linde function instead of the peak top time. Dependences of the viscosity correcПоказать полностьюted electrophoretic mobility on HP-beta-CD concentration were not described on the basis of only complexes with 1:1 stoichiometry due to the fact that these binding curves did not reach a plateau. However, the dependences were well described taking into account both 1:1 and 1:2 complexes. The presence of higher order equilibria was also revealed by x-reciprocal plots. The values of apparent binding constant logarithm, obtained for the first time, for 1:1 and 1:2 HP-beta-CD complexes of betulin 3,28-diphthalate and betulin 3,28-disuccinate with 95% confidence interval limits in brackets are the same within error and are equal to 4.85 (4.73-4.95), 8.56 (7.75-8.82), 4.92 (4.86-4.97), and 8.54 (8.23-8.72) at 25 degrees C, respectively. These values for 1:1 and 1:2 HP-beta-CD complexes of betulin 3,28-disulfate at 25 degrees C are 4.61 (4.57-4.64) and 7.11 (6.57-7.34), respectively. The binding constants for betulin 3,28-disulfate agree with the previously obtained results from the separation in the thermostatted capillary segment.
Журнал: ELECTROPHORESIS
Номера страниц: 700-707
ISSN журнала: 01730835
Место издания: HOBOKEN
Издатель: WILEY