Microneedles Inspired by Bee Stingers Could Improve Sustained Drug Delivery

Microneedles Inspired by Bee Stingers Could Improve Sustained Drug Delivery



Researchers from Chung-Ang University in South Korea have developed a novel microneedle drug delivery system that was inspired by the structure of bee stingers. The new technology, called Electrospun Web Microneedles (EW-MNs), is described in Advanced Healthcare Materials. The EW-MNs could address long-standing limitations of traditional injections for transdermal drug delivery and mark an improvement in current microneedle approaches for conditions such as Alzheimer’s and Parkinson’s disease.

“Unlike traditional rigid microneedles, which can cause irritation during prolonged use, our EW-MNs are soft, breathable, and remain anchored to the skin just like a bee stinger,” said study leader Wonku Kang, PhD, a professor in the College of Pharmacy, Chung-Ang University.


Traditional microneedles are made from rigid polymers or metals and are only suitable for short-term applications since they can cause discomfort, foreign-body sensations, and skin irritation when used for extended periods. These effects are particularly problematic for patients requiring sustained medication, such as those with disorders of the central nervous system (CNS), such as Alzheimer’s and Parkinson’s.

To overcome these limitations, the Chung-Ang team employed an electrospinning technique to fabricate microneedles with a nanoscale fibrous web coating. Using this technique, the fibers around metal microneedle tips mimic the barbed structure of a bee stinger. As a result, the microneedles anchor securely into the skin and maintain prolonged contact for steady drug delivery. The patches are completed by attaching the microneedles to an adhesive tape and backing layer, forming a flexible, breathable patch.

To test the new EW-MNs, the researchers used guinea pig models with doses of rivastigmine, a drug used to treat Alzheimer’s and Parkinson’s disease, which enhances acetylcholine levels. Current applications of this drug via either oral capsules or transdermal patches often result in inconsistent plasma drug levels and poor adherence due to side effects and discomfort.

According to the team’s in vitro and in vivo pharmacokinetic studies, their microneedle patch showed a 2.5-fold increase in area under the curve (AUC) and significantly prolonged the presence of the drug in the bloodstream, pointing toward a more efficient and sustained release profile than existing delivery methods.


“Given the demands of CNS diseases, particularly the necessity for continuous pharmacological intervention, there is a clear need for wearable drug delivery systems capable of providing sustained therapeutic management in a user-independent manner,” the researchers wrote.

The development of these new microneedles builds upon earlier research efforts that have explored the use of wearable microneedles for both diagnostics and real-time drug delivery applications. But the earlier efforts primarily relied on rigid materials and could not resolve user discomfort or prolonged wearability challenges.

The key innovation for creating these new microneedles was controlled electrospinning of polycaprolactone (PCL), a biocompatible and biodegradable polymer. To achieve their results, the researchers needed to tweak a number of variables such as electrospinning voltage, grounding conditions, and spin time. “To achieve a bee-stinger-inspired structure, precise control of the electric field during the electrospinning process was essential,” the researchers wrote.

The team will now turn its attention to testing the platform for other CNS-targeting drugs and exploring its use in pediatric, geriatric, and emergency care settings. They also plan to study the broader pharmacokinetic profiles across species and extend applications to diseases beyond the CNS, where long-term, steady-state drug administration is needed.