New platforms for multi-functional ocular lenses: engineering double-sided functionalized nano-coatings

A scalable platform to prepare multi-functional ocular lenses is demonstrated. Using rapidly dissolving polyvinylpyrrolidone (PVP) as the active stabilizing matrix, both sides of ocular lenses were coated using a modified scaled-up masking electrohydrodynamic atomization (EHDA) technique (flow rates variable between 5 and 10 µL/min, applied voltage 4–11 kV). Each side was coated (using a specially designed flip-able well) selectively with a pre-determined morphology and model drug substance. PVP nanoparticles (inner side, to be in contact with the cornea, mean size <ca.100 nm) were encapsulated with a probe (flourescein dye) and PVP nanofibres (outer side, to be exposed to air and eye lid, mean width size <ca.200 nm) were encapsulated with chloramphenicol (5 w/w% PVP). Release of the probe and anti-microbial activity (using Staphylococcus aureus NCTC 6571) were demonstrated based on rapid dissolution and contact of PVP model substance matrix. Adapting these findings further for advanced EHDA technologies (encapsulation layering, controllable size and deposition and multi-phase media deposition options) and intrinsic material properties (functional polymers/excipients and advanced controlled release strategies) suggests several therapeutic platforms for ocular lenses can be further developed at ambient temperature and pressure. These provide multi-functional properties (in personalized delivery, nanomedicine and nanosensors) from a single drug delivery device.