Solid lipid nanoparticles (SLNs) are effective for drug delivery as they can improve the drug release and its bioavailability while reducing its side effects. An acid-treated montmorillonite (acid-Mt) was first intercalated with Betaxolol Hydrochloride (BH) in the interlayers and this nanocomposite was encapsulated by SLNs (Mt-BH-SLNs) using an emulsion evaporation-low temperature solidification method. The successful intercalation of BH in montmorillonite was verified by showing an increase in d 001 value from 1.54 to 1.93 nm using X-ray diffraction (XRD). The successful encapsulation of BH intercalated Mt (Mt-BH) and formation of a new nanocomposite of Mt-BH-SLNs was indicated by the disappearance of the characteristic band at 1512 cm − 1 representing C-H aromatic ring of BH in infrared spectrum (IR). The mean particle size of Mt-BH-SLNs was ca. 150 nm, which is favorable for cornea permeation. The experimental results of in vitro release, ocular irritation and in vitro corneal penetration indicated that the Mt-BH-SLNs possessed a controlled release of BH for a period of 12 h and led to a lower stimulation than that of BH solution.
