Background
Angiogenic ocular diseases address the main source of vision impairment or irreversible vision loss. The angiogenesis process depends on the balance between the pro-angiogenic and anti-angiogenic factors. An imbalance between these factors leads to pathological conditions in the body. The vascular endothelial growth factor is the main cause of pathological conditions in the ocular region. Intravitreal injections of anti-angiogenic drugs are selective, safe, specific and revolutionized treatment for ocular angiogenesis. But intravitreal injections are invasive techniques with other severe complications. The area of targeting vascular endothelial growth factor receptors progresses with novel approaches and therapeutically based hope for best clinical outcomes for patients through the developments in anti-angiogenic therapy.
Main text
The present review article gathers prior knowledge about the vascular endothelial growth factor and associated receptors with other angiogenic and anti-angiogenic factors involved in ocular angiogenesis. A focus on the brief mechanism of vascular endothelial growth factor inhibitors in the treatment of ocular angiogenesis is elaborated. The review also covers various recent novel approaches available for ocular drug delivery by comprising a substantial amount of research works. Besides this, we have also discussed in detail the adoption of nanotechnology-based drug delivery systems in ocular angiogenesis by comprising literature having recent advancements. The clinical applications of nanotechnology in terms of ocular drug delivery, risk analysis and future perspectives relating to the treatment approaches for ocular angiogenesis have also been presented.
Conclusion
The novel ocular drug delivery systems involving nanotechnologies are of great importance in the ophthalmological sector to overcome traditional treatments with many drawbacks. This article gives a detailed insight into the various approaches that are currently available to be a road map for future research in the field of ocular angiogenesis disease management.
Elevated bioavailability is an advantage for most of the poorly soluble drugs. The present scenario of research investigation is concentrated on different techniques to alter the solubility characteristics of weakly soluble drugs and crystallization phenomenon is one amongst them. The low solubility problem can be solved by changing the crystal habit of drug. So, in the present research an attempt has been made to modify the solubility characteristics of Nifedipine, an anti-hypertensive drug, using solvent change method, Solvent evaporation technique and solvent change precipitation technique. Among them solvent change method gave a better formulation (NIF-MC-6) showing better dissolution (91.36% at the end of 240mins) as compared to pure drug and micro-crystals formulated using other methods. The formulated crystals of Nifedipine were subjected to various physicochemical parameters like size distribution, solubility studies, in-vitro dissolution studies, drug content, FT-IR, DSC, crystallographic studies by PXRD and crystal morphology by SEM studies. The micro-crystals produced with PVPK30 and chloroform. FT-IR Results showed that there was no chemical interaction between the drug, solvent and the stabilizer. PXRD of micro-crystals showed higher peak height than pure drug indicating that crystal habit modification occurred in the microcrystals without any polymeric changes and were found to be smaller in size than pure drug and free from any interactions. SEM studies indicated that the crystals are present in rectangular and square shape. The DSC curve showed that Nifedipine appeared an endothermic peak at about 174 0 C corresponding to its melting. However, the crystals prepared with PVP K30 shows shift of endothermic peak towards lower temperature at 170.82 0 C respectively, dictating decreased melting point of the drug in the formed crystals, which accounted for increased solubility of the drugs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.