Antiangiogenic effect of silicate nanoparticles on corneal neo-vascularisation induced by vascular endothelial growth factor

Silicate nanoparticle; Corneal neovascularisation; Vascular endothelial growth factor Abstract Corneal neo-vascularisation (NV) is a major sight-threatening condition and is caused by infections, degenerative disorders, inflammation and long-time contact lens wear. Corneal NV occurs when the balance between angiogenic and antiangiogenic factors is tipped towards angiogenic molecules. The abnormal vessels may decrease corneal clarity and vision, lead to inflammation and corneal scarring and worsen the prognosis of penetrating keratoplasty if needed. There is no definite therapeutic approach for cornea NV. Medical and surgical therapies used to reduce corneal NV include corticosteroids and non-steroidal anti-inflammatory agents, laser photocoagulation and needle diathermy. Many of these therapies not only have demonstrated limited success but also have associated adverse effects. Therefore, it is very necessary to provide novel therapeutic approaches. Recently, anti-vascular endothelial growth factor (anti-VGEF) therapy has been introduced for the management of corneal NV. Herein, we hypothesise the use of silicate nanoparticles (SiNPs) as a novel treatment for corneal NV. The penetration rate of SiNPs into the cornea is attributed to the size of nanoparticles. Therefore, different sizes of SiNPs (20–50 nm) would be prepared and loaded onto the tissue to determine corneal permeability towards them. In addition, SiNPs would be administered into the eye by topical, subconjunctival and corneal intrastromal injection and accumulate in newly formed vessels. This hypothesis has been developed by emphasising on the synthesis of SiNPs, characterisation of size-dependent properties and surface modification for the preparation of homogeneous