Thiolated cyclodextrins: Mucoadhesive and permeation enhancing excipients for ocular drug delivery

Thiolated β-cyclodextrin (β-CD) has the potential to enhance mucoadhesive and permeation enhancing properties on ocular mucosa. β-CD was synthesized via replacement of all primary hydroxyl groups backbone by halogen followed substitution with thiol groups. The structure confirmed FT-IR 1H NMR spectroscopy. CD characterized for hemolytic effect, irritation, solubility enhancement, viscoelastic behavior properties. Moreover, effect thiolated oligomer different tissues including conjunctiva, sclera cornea evaluated sodium fluorescein (Na-Flu) as a marker. displayed 5360 ± 412 µmol/g newly did not show any red blood cells at concentration 0.5% (m/v) an incubation period 3 h minimal corneal irritation effects without inflammation within 72 h. exhibited 5.3-fold improved aqueous compared unmodified β-CD. (0.5% m/v) enhanced viscosity mucus up 6.2-fold 4 provided 26-fold prolonged residence time due mucoadhesion. Na-Flu 9.6-, 7.1- cornea, respectively. Based these findings, might be promising auxiliary agent drug delivery.