Novel Eye Drop Container for Reconstitution of a Lyophilized Product

Following an injury to the cornea, mesenchymal stem cells (MSCs) have been shown to enhance cell proliferation and wound healing while reducing scar formation and hemorrhaging. However, their limited shelf-life poses a problem for clinical application. Lyophilization, a method of freeze-drying biologically active molecules, has recently been validated as a potential solution to this challenge. Lyophilized MSCs must be reconstituted, typically with water, before the solution can be dispensed onto the cornea. Currently, there are no commercially available eyedroppers that separately house water and the lyophilized product and provide a mechanism for reconstitution. Thus, the team developed a novel eye drop container that can hold 0.3-3 mL of solution, achieve reconstitution in under 60 seconds, and mix the two products thoroughly together, leaving no residual powder. The device consists of a 5 mL bottle with a membrane pouch that isolates the lyophilized MSCs at the opening of the bottle. The water is contained in the bottom half of the bottle, below the pouch, thus maintaining separation from the lyophilized product. The user initiates reconstitution by puncturing the membrane with a needle-nozzle apparatus. Once punctured, the contents of the membrane pouch fall directly into the water, after which the bottle can be shaken, and the resulting solution used to administer eye drops for treatment. The device was tested to meet adequate reconstitution and volume output by colorimetric assay and measurement of droplet mass, respectively. Over numerous trials, we found our device to meet rigorous acceptance criteria, suggesting the design provides a convenient and efficient way of delivering MSCs for patient recovery. We believe our device will help aid in the use of novel clinical treatments for corneal wound recovery by enabling the reconstitution of a lyophilized stem-cell product.