Аннотация:Introduction. The ability of the small intestine (internalization) to absorb water-soluble anticancer cytostatics
determines the possibility of their oral administration. The ex-vivo express method that simulates the
internalization of substances using a modified technique of an isolated «inverted» segment of the rat small
intestine with flash chemiluminescence is adequate to solve the problem. Objectives: to evaluate the
absorption of the new water-soluble anticancer cytostatics with different properties from the rat small intestine
for preclinical study by oral administration. Material and Methods. Conjugated with acridinium (Acridinium
NHS Ester, Toronto Research Chemicals, Canada) cytostatics were studied: low molecular weight (1)
Anthrafuran-Acridinium (MW 0.8 kDa) and high molecular weight (2) Aimpila-Acridinium (MW 105 kDa) and
(3) L-lysine-α-oxidase (LO-Acridinium, MW 122 kDa). Absorption was determined in a modified model of an
isolated «inverted» segment of the rat small intestine using flash-chemiluminescence with the calculation of the
relative light units (RLU). Results. It was shown that the absorption level of acridinium-conjugated cytostatics
depending on molar concentration ranged from 55 % (1) to 1.7–11 % (2, 3) and 2500 (1) to 9.2–188 nmol/l (2,
3), respectively. The level of internalized Anthrafuran-Acridinium (55 %) was consistent with the known value of
the effective non-conjugated cytostatic oral dose, which was two times higher than equitherapeutical parenteral
dose: 100 mg/kg vs 50 mg/kg. Conclusion. The data obtained allow us to consider ex vivo express method
for preclinical study of the various water-soluble anticancer cytostatics for screening and identification of an
opportunity for oral administration and estimation of starting dose. The method has a good correlation with in
vivo tests and economically favorable due to a quick response and small number of the tested agent.