Latch Applicator for Efficient Delivery of Dissolving Microneedles Based on Rapid Release of Elastic Strain Energy by Thumb Force. (6th January 2023) - Kang, Geonwoo
Abstract: Dissolving microneedle (DMN) is an attractive alternative to parenteral and enteral drug administration owing to its painless self‐administration and safety due to non‐generation of medical waste. For reproducible and efficient DMN administration, various DMN application methods, such as weights, springs, and electromagnetic devices, have been studied. However, these applicators have complex structures that are complicated to use and high production costs. In this study, a latch applicator that consists of only simple plastic parts and operates via thumb force without any external complex device is developed. Protrusion‐shaped latches and impact distances are designed to accumulate thumb force energy through elastic deformation and to control impact velocity. The optimized latch applicator with a pressing force of 25 N and an impact velocity of 5.9 m s −1 fully inserts the drug‐loaded tip of the two‐layered DMN into the skin. In an ovalbumin immunization test, DMN with the latch applicator shows a significantly higher IgG antibody production rate than that of intramuscular injection. The latch applicator, which provides effective DMN insertion and a competitive price compared with conventional syringes, has great potential to improve delivery of drugs, including vaccines. Abstract : The latch applicator has a simple structure that enables efficient skin insertion of dissolving microneedle patches with optimized force and velocity. This system consists of three disposable plastic parts; therefore, it is cost‐competitive and easy to use as it operates with thumb force without complicated external devices such as mechanical springs or electromagnets.