Smart microneedle coatings for controlled delivery and biomedical analysis

Area of Science:

• Materials Science
• Biomedical Engineering
• Nanotechnology

Background:

• Microneedles (MNs) offer minimally invasive drug delivery and diagnostics.
• Developing precise and scalable methods for MN coating is crucial for advanced applications.

Purpose of the Study:

• To demonstrate an unconventional approach for preparing smart microneedle (MN) coatings using electrohydrodynamic atomisation (EHDA).
• To achieve controlled deposition of nano- and micro-scale pharmaceutical coatings directly onto MNs.

Main Methods:

• Utilised stainless steel MNs coupled to a ground electrode in an EHDA setup.
• Varied deposition distance and collection methodology with an ethanol:methanol vehicle system.
• Formulated coatings with fluorescein dye and polyvinylpyrrolidone (PVP), controlling particle and fiber sizes via flow rates (5-50 µL/min) and applied voltage (6-19 kV).

Main Results:

• Successfully prepared nano- (100 nm) and micro- (up to 3 µm) scale particles and micro-scale fibers (400 nm to 1 µm) directly on MNs.
• Demonstrated controlled and selectable deposition of coating materials.
• EHDA process enabled room temperature fabrication with controlled output.

Conclusions:

• EHDA is a viable and unconventional method for fabricating smart MN coatings.
• The developed technique offers potential for multiple targeting and analysis applications.
• EHDA process shows significant scale-up potential for emerging MN drug delivery systems and lab-chip testing devices.