Použitím absorpčnej spektroskopie UV/VIS s pyrénom bola preskúmaná micelizácia vybraných kvartérnych amóniových solí odvodených od heptakaínu (látky s pracovným označením H22, H26, H27, H29, H34, H37, H + Al a H + B) vo vodných prostrediach a derivát H34 v 3 mol/l etanolovom roztoku pri teplote 25 °C. V homologickom rade študovaných bromidov H22, H26, H27 a H29 hodnoty cmc exponenciálne závisia od počtu atómov uhlíka nC v hydrofóbnom reťazci: ln (cmc) = –3,131–0,421nC. Voľná Gibbsova energia prenosu jednej metylénovej skupiny alkylového reťazca z vodnej fázy do vnútra micely pri teplote 25 °C má hodnotu (–0,421 ? 0,034)RT.

Micellization of selected quaternary ammonium compounds derived from heptacaine have been studied by absorption spectroscopy in the UV/VIS spectral region with the use of a pyrene probe. The compounds studied in the aqueous solution have been marked as H22, H26, H27, H29, H34, H + Al and H + B and the derivative marked as H34 was studied in a 3 mol/l ethanol solution at the temperature of 25 °C. In the homologous series of the studied bromides H22, H26, H27 and H29, cmc was observed to be dependent on the number of carbon atoms nc in the hydrophobic chain: ln (cmc) = –3.131–0.421nC. The Free Gibbs energy necessary for the transfer of a methyl group of the alkyl chain from the water phase to the inner part of the micelle at the temperature of 25 °C is (–0.421 ? 0.034)RT.

Katedra farmaceutickej chémie Farmaceutická fakulta UK Bratislava SR

Study of local anaesthetics: Part 206* Micellization of selected of quaternary ammonium salt derived from heptacaine