Summary
The majority of diseases that cause substantial and irreversible vision loss resulting from pathologic ocular neovascularization such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity and ocular tumours. Poor drug delivery to lesions in patient’s eyes is a major obstacle to the treatment. Nanotechnology provides novel opportunities to overcome the limitations of conventional drug delivery systems to reach the back of the eye through fabrication of nanostructures capable of encapsulating and delivering small molecules. This review article summarizes the current ocular drug delivery systems that are associated with development of nanocarriers for treatment of ocular disease in back of the eye. The application …show more content…
Topical administration has long been the primary route of ocular drug delivery to treat disorders ranging from superficial conditions to intravitreal diseases. When eye drop is administered to the surface of the eye, only a small amount actually reaches the intraocular tissues because most gets washed away with the tear fluid or gets absorbed systemically through the nasolacrimal duct system[9]. The remarkably low penetration of drug across the epithelial surface of cornea to the vitreous chambers is another issue[10]. Intravitreal injection is the currently preferred route of delivery to treat diseases of the posterior segment because it directly delivers drugs to the eye lesions. It is generally safe but sometimes it poses the risks of blinding complications and they include bleeding, retinal tear or detachment, traumatic lens injury, serious intraocular infection and increased intraocular pressure. To maintain drug efficacy, the treatment must be continued on a monthly basis. Therefore, there is a need for a safer, more effective and convenient delivery system which could deliver drug to the posterior segment of the …show more content…
Advanced ocular drug delivery systems are needed to optimize and control delivery of ocular therapeutics to the target sites either by increasing their penetration or by prolonging contact time of carrier with the ocular surface. Nanotechnology refers to the use of nanometre scale substances to develop new functions for these substances and then improves their properties. It provides novel opportunities to overcome the limitations of conventional drug delivery systems through the fabrication of nanostructures capable of encapsulating and delivering small molecules. Nanoparticles have small sizes ranging from 1-200 nm which can improve the bioavailability of therapeutic agents and pass through biological barriers of the eye[8]. Another important characteristic of nanoparticles is that they can be fabricated bespoke through chemical processes. For examples, particulate nanocarrier-based delivery systems have improved the pharmacokinetic and pharmacodynamic properties of various types of drug molecules for the eye[11]. Advancements in material designs and formulations for new nanoparticles have offered exciting possibilities to deliver drugs to the retina[12]. Nanocarrier-based drug delivery system can be used for treatment diseases in the posterior segment of the eye, which can overcome the issue of frequent intravitreal
The majority of diseases that cause substantial and irreversible vision loss resulting from pathologic ocular neovascularization such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity and ocular tumours. Poor drug delivery to lesions in patient’s eyes is a major obstacle to the treatment. Nanotechnology provides novel opportunities to overcome the limitations of conventional drug delivery systems to reach the back of the eye through fabrication of nanostructures capable of encapsulating and delivering small molecules. This review article summarizes the current ocular drug delivery systems that are associated with development of nanocarriers for treatment of ocular disease in back of the eye. The application …show more content…
Topical administration has long been the primary route of ocular drug delivery to treat disorders ranging from superficial conditions to intravitreal diseases. When eye drop is administered to the surface of the eye, only a small amount actually reaches the intraocular tissues because most gets washed away with the tear fluid or gets absorbed systemically through the nasolacrimal duct system[9]. The remarkably low penetration of drug across the epithelial surface of cornea to the vitreous chambers is another issue[10]. Intravitreal injection is the currently preferred route of delivery to treat diseases of the posterior segment because it directly delivers drugs to the eye lesions. It is generally safe but sometimes it poses the risks of blinding complications and they include bleeding, retinal tear or detachment, traumatic lens injury, serious intraocular infection and increased intraocular pressure. To maintain drug efficacy, the treatment must be continued on a monthly basis. Therefore, there is a need for a safer, more effective and convenient delivery system which could deliver drug to the posterior segment of the …show more content…
Advanced ocular drug delivery systems are needed to optimize and control delivery of ocular therapeutics to the target sites either by increasing their penetration or by prolonging contact time of carrier with the ocular surface. Nanotechnology refers to the use of nanometre scale substances to develop new functions for these substances and then improves their properties. It provides novel opportunities to overcome the limitations of conventional drug delivery systems through the fabrication of nanostructures capable of encapsulating and delivering small molecules. Nanoparticles have small sizes ranging from 1-200 nm which can improve the bioavailability of therapeutic agents and pass through biological barriers of the eye[8]. Another important characteristic of nanoparticles is that they can be fabricated bespoke through chemical processes. For examples, particulate nanocarrier-based delivery systems have improved the pharmacokinetic and pharmacodynamic properties of various types of drug molecules for the eye[11]. Advancements in material designs and formulations for new nanoparticles have offered exciting possibilities to deliver drugs to the retina[12]. Nanocarrier-based drug delivery system can be used for treatment diseases in the posterior segment of the eye, which can overcome the issue of frequent intravitreal