Microneedles for Drug Delivery in Aquaculture

Abstract

Aquaculture is a rapidly growing industry that can address increased food demand from population growth as well as overfishing and other environmental concerns from traditional fishing methods. However, a major challenge in aquaculture is the spread of disease from close quarters of the fish. Current fish vaccination methods include oral, immersion, and injection, with injection being the most effective but also the most cumbersome to implement. This project proposes an alternative by using biocompatible microneedles that can be applied in situ and dissolve to release the drug. The focus of this project is the needle fabrication method and coating selection to provide necessary mechanical strength to withstand aquatic environments. It was found that hollow, silk microneedles coated in shellac/ethanol coatings of 33.3% w/w following the two-step method of full dip coating then tip-only dip coating was able fully coat microneedles. Compression testing was done on individual needles in their dry state and after 30 minutes of soaking in deionized water and seawater. A constant increase in force from the onset of testing across all needles showed little difference between all samples observed, indicating that the needle should be able puncture fish skin.