Hpbcd

All reagents were purchased from Merck (Budapest, Hungary), unless otherwise indicated. HPBCD and 6-deoxy-6-[(5/6)-fluoresceinylthioureido]-(2-hydroxypropyl)-β-cyclodextrin (FITC-HPBCD) were the products of Cyclolab Ltd. (Budapest, Hungary). FITC-HPBCD product number: CY-F-2005.1, average degree of substitution (DS) determined by NMR was DS = 0.7 for FITC and DS = 4.1 for hydroxypropyl group. FITC-HPBCD was purified by extensive dialization to remove impurities. Free dye and 6-deoxy-6-monoamino-HPBCD contents were tested by capillary electrophoresis (CE) and were below limit of detection. Stock solution of the cyclodextrin was prepared in sterile distilled water, from which treatment solutions were made in culture medium.

Chrysin–cyclodextrin complexes were produced with HPBCD and RAMEB (CycloLab, Budapest, Hungary), as previously described [31 (link)]. The complexes were obtained by the solvent evaporation method. Chrysin (Merck, Darmstadt, Germany) was dissolved first in 96% ethanol to obtain a 4 mg/mL Chrysin solution, ed by RAMEB and HPBCD dissolution in the ethanolic Chrysin solution. Cyclodextrins and Chrysin were concentrated and dried during ethanol evaporation at 30 °C, and ground under continuous mixing.