During the past decades, researchers involved in the development of ophthalmic pharmaceuticals have understood that ophthalmic drug delivery is a challenging subject for optimization. Normal vision is dependent upon the optimal functioning of ocular barriers and intact membranes that function to selectively regulate the environment of ocular tissues. Novel pharmacotherapeutic modalities have aimed to overcome the biological barriers which can impede efficient ocular drug delivery. To explore the impact of ocular barriers on research related to ophthalmic drug delivery and targeting, herein we provide a review of the literature of work carried out on the biological constraints and new approaches to ophthalmic drug delivery.

QSAR studies of thirty 2-arylbenzoxazole derivatives are carried out to probe their inhibitory activity against Cholesteryl Ester Transfer Protein (CETP). QSAR models have been obtained using multiple linear regression (MLR) analysis after manifestation of forward selection algorithm to cull significant descriptors out of descriptor’s pool. QSAR models are elected with adherent set of statistical parameters with R2=0.9431 and R2=0.9069. Validation of modeling includes method of Y-Scrambling and in addition to this, some other methods of validation. Moreover, QSAR approach of 2-arylbenzoxazoles are also attempted, supported and validated by flexible docking studies as well. The search strategies include evolutionary algorithm and edited form of Gehlhaar PLP scoring function. The same set of thirty candidates from 2-arylbenzoxazole derivatives is processed in molecular docking and their docking scores are found in agreement with QSAR studies reported. Remarkable CETP inhibitory activity is exhibited by a 2-arylbenzoxazole derivatives molecule 29C with most comprehensive set of interactions with rerank scores -102.167 and RMSD values 1.104. Hydrogen bond interactions along with hydrophobic and electrostatic interactions are mapped to confirm their potencies.

The ethanolic extract of Clitoria ternatea L. was evaluated for its in vitro cytotoxic and antioxidant activities. The extract showed potent cytotoxic activity in trypan blue dye exclusion method using DLA cell lines with EC50 value of 305μg/ml and exhibited a dose dependent decrease in cell count for all the concentrations tested. The antioxidant activity was evaluated by DPPH free radical method. The extract exhibited potent antioxidant activity with an EC50 of 36.5μg/ml.