Enhancing Corneal Drug Penetration Using Penetratin for Ophthalmic Suspensions.

Eye drops, including solutions and suspensions, are essential dosage forms to treat ophthalmic diseases, with poorly water-soluble drugs typically formulated as ophthalmic suspensions. In addition to low bioavailability, suspensions exhibit limited efficacy, safety, and usability due to the presence of drug particles. Improving bioavailability can reduce the drug concentrations and the risk of problems associated with suspended drug particles.

Exploring Cell-Penetrating Peptides as Penetration Enhancers in Eye Drop Formulations Using a Reconstructed Human Corneal Epithelial Model.

Ocular tissues function as biological barriers that hinder drug delivery, depending on the target tissue and route of administration, and must be overcome to achieve the desired therapeutic effect. Penetration enhancers have long been investigated to improve corneal drug penetration via eye drop instillation; however, further development is warranted owing to potential safety concerns. In the present study, we focused on cell-penetrating peptides (CPPs) as a penetration enhancer to address the requirements and explored CPP candidates suitable for corneal drug delivery.

Effect of diffusive direction across the skin on the penetration profile of chemicals in vitro.

Skin has various types of transporters and is a biochemically active organ. These aspects of skin influence the distribution of chemicals in skin and their elimination from skin. The biochemical and histological variations of the skin must be taken into account when conducting transdermal penetration research.