Optimizing CNC milling parameters for manufacturing of ultra-sharp tip microneedle with various tip angles

Area of Science:

• Biomedical Engineering
• Materials Science

Background:

• Microneedle technology offers advanced transdermal drug delivery.
• Diverse fabrication methods exist for microneedle development.

Purpose of the Study:

• To investigate Computer Numerical Control (CNC) milling for microneedle master mold fabrication.
• To analyze the impact of machining parameters on microneedle tip sharpness and geometry.

Main Methods:

• Utilized CNC milling to create microneedle master molds.
• Examined feed rate and ramp angle effects on tip sharpness and diameter.
• Assessed microneedle performance through compression, insertion, and diffusion tests.

Main Results:

• Increased feed rate and ramp angle reduced machining time but affected tip quality.
• Optimal conditions found at 100 mm/min feed rate and 1.5° ramp angle.
• 50° tip angle needles achieved the sharpest tips (~3.3 µm) with diameters <10 µm.

Conclusions:

• CNC milling is effective for fabricating sharp microneedle tips.
• Machining parameters significantly influence microneedle geometry and sharpness.
• Optimized CNC parameters enable precise microneedle production for transdermal delivery applications.