Table 4 Summary of common microneedle fabrication methods

Micromolding

Simple and cost effective; reusability of molds

Demolding challenges; mold fabrication complexity; batch variation

[152, 158,159,160,161]

Photolithography

One-step simple fabrication process

Blunt needle tips; material limitations

[153, 162, 163]

3D printing

Direct fabrication; high printing resolution; intricate and precise structure; customizable design

Expensive equipment; equipment-dependent resolution; slow printing speed

[133, 155, 164,165,166,167]

Etching

High precision; complex structure fabrication

Rough surface; complicated fabrication process; environmental concerns; difficulty in integrating drug loading

[156, 168,169,170]

DAB method

Drug activity; low cost; simple equipment; material versatility

Limited microneedle structure complexity; limited scalability; environmental sensitivity

[157, 171, 172]