Table 2.

Classification of microneedles based on the method of fabrication for diagnosis

Microneedle type	Fabrication method	Drug	Reference
Solid MN	Micro-molding, etching, 3D printing, lithography	Amantadine, pramipexole	(Hoang et al. 2015) (Hoang et al. 2015)
Coated MN	Micro-molding, photolithography	Lidocaine	(Zhang et al. 2012)
Hollow MN	Photolithography, 3D printing	Etanercept, phenylephrine	(Cao et al. 2019) (Jun et al. 2015)