Table 1 Comparison of the characteristics of the main fabrication methods for MNs.
From: Introducing all-inkjet-printed microneedles for in-vivo biosensing
Category | Fabrication method | Material | Tip min. dimension (µm) | Min. steps required | Time/MN | MNs type | Conductive MNs | References |
|---|---|---|---|---|---|---|---|---|
Lithography | Wet chemical etching | Silicon | < 1 | > 2 | min (P) | S/H | Semicond | |
Reactive ion etching | < 1 | > 2 | min (P) | S/H | Semicond | |||
Lithography + electroforming | < 1 | > 3 | min (P) | S/H | Semicond | |||
Drawing lithography | < 10 | > 2 | min (P) | S/H | Semicond | |||
Photochemical etching | Metal, Silicon | < 1 | > 2 | min (P) | S/H | Semicond | ||
Moulding and drilling | Hot embossing | Polymers | < 1 | 1 | sec (P) | S/H | No | |
Injection molding | < 1 | 1 | sec (P) | S/H | No | |||
Micromilling | Polymers and metals | ≈ 30 | 1/2 | min (OPT) | S (H) | Yes, solid substrate | ||
Laser drilling | ≈ 30 | 2 | sec (OPT) | S | Yes | |||
3D printing | SLA | Polymers | 80 | 1 | min (OPT) | S/H | No | |
FDM | 170–220 | 1 | min (OPT) | S | No | |||
DLP | 40 | 1 | min (OPT) | S/H | No | |||
2PP | 6 | 1 | min(OPT) | S/H | No | |||
Printing of AgNPs | Metals | 30 | 1 | min (SPT) | S | Yes, thin substrate | This work |
