Nanoparticulate Systems
Nanoparticles: Facilitate drug penetration via paracellular/transcellular pathways, enhancing corneal bioavailability.
Liposomes: Encapsulate hydrophilic/lipophilic drugs and merge with membranes to improve delivery.
Dendrimers: Branched polymers modified for targeted delivery.
Mucoadhesive Polymers
Polymers like chitosan and hyaluronic acid increase drug retention on the ocular surface, enhancing absorption.
Prodrugs
Drug derivatives designed for improved penetration and stability, converted to active drugs inside the eye (e.g., dipivefrin for epinephrine).
Iontophoresis
Uses mild electric currents to drive charged drugs into the eye, enhancing corneal penetration.
Microneedles
Minimally invasive tiny needles deliver drugs to targeted sites, such as the suprachoroidal space.
Implants and Devices
Intravitreal Implants: Provide sustained drug release targeting the retina.
Punctal Plugs: Slow drug release via tear ducts.
Periocular and Intravitreal Injections
Direct injections bypass anterior barriers; intravitreal for retina, periocular for surrounding tissues.
Sonophoresis
Ultrasound waves create micropores in the cornea to enhance drug permeability.
Penetration Enhancers
Surfactants, bile salts, and cyclodextrins improve solubility and temporarily open tight junctions.
These are all the Methods to Overcome Intraocular Barriers