Microneedle-Based Technologies for Long-Acting Transdermal Drug Delivery in Wearable Devices

Area of Science:

• Biomedical Engineering
• Materials Science
• Pharmacology

Background:

• Microneedles (MNs) offer a minimally invasive approach for transdermal drug delivery.
• Various MN types exist, including solid, coated, dissolving, hollow, hydrogel-forming, and biodegradable.
• Sustained drug release is crucial for effective long-term therapy.

Purpose of the Study:

• To systematically review recent advancements in long-acting microneedle-based transdermal drug delivery systems.
• To discuss design strategies and material platforms for sustained drug release.
• To identify challenges hindering clinical translation.

Main Methods:

• Literature review of recent scientific publications on microneedle technology.
• Categorization of microneedle types based on their delivery mechanisms.
• Analysis of material properties and drug carrier incorporation for sustained release.

Main Results:

• Biodegradable polymers (PLA, PLGA, PCL, SF, CS) enable prolonged drug release via tunable degradation.
• Incorporation of liposomes and polymeric nanoparticles/microparticles enhances drug loading and release duration.
• Different microneedle designs (solid, coated, dissolving, hollow, hydrogel-forming, biodegradable) offer varied release profiles.

Conclusions:

• Long-acting microneedle systems show significant promise for transdermal drug delivery.
• Material selection and advanced drug carriers are key to achieving sustained release.
• Overcoming manufacturing consistency, sterility, and in vivo validation challenges is critical for clinical adoption.