Preparation and characterization of soluble branched ionic β-cyclodextrins and their inclusion complexes with triclosan

• Branched anionic and cationic β-cyclodextrins were obtained from parent β-CDs.
• Water solubility of ionic branched β-cyclodextrins (bβCD) was higher than neutral ones.
• No cytotoxic effects were observed for ionic bβCDs.
• Ionic bβCDs form complexes with triclosan but show a complexation limit.
• Complexes of triclosan with anionic bβCDs showed higher stability constant than with cationic bβCDs.

This study aims to synthesize, characterize and investigate the water solubility and cytotoxicity of branched anionic/cationic β-cyclodextrins (bβCDs) obtained by reaction with epichlorohydrin and chloroacetic acid or choline chloride, respectively, by a single step polycondensation reaction. Obtained ionic bβCDs were investigated as an attempt to comparatively study anionic and cationic bβCDs. Water solubility of both ionic derivatives was similar (400 mg/mL) at neutral and basic pHs and remarkably higher than that of their neutral homologues. Additionally, a pH-dependent solubility of anionic bβCDs was observed. Cytotoxicity of ionic bβCDs was evaluated on Human colon carcinoma Caco-2 cells and high cell viability (>99%) was observed in the range of 0–100 mg/mL for anionic and cationic samples, in the same range of that of neutral and parent β-CDs. Additionally, complexes formation capacity with triclosan, a poor water soluble antimicrobial agent, was confirmed by several techniques observing a complexation limit around 4 mg/mL for both systems and higher stability constant for anionic bβCDs than cationic derivatives.