Microneedle structure and biodegradable microneedle thereof

A biodegradable microneedle of a microneedle structure defining a central axis, comprising:

• a first step portion;
• and
• a second step portion taperedly extending from the first step portion along the central axis,
• wherein the biodegradable microneedle has a total height along the central axis and a maximum internal diameter along a direction perpendicular to the central axis, wherein the total height is within a range of 380-430 μm, and an aspect ratio defined by the total height divided by the maximum internal diameter is within a range of 1.2-2.2, wherein in a cross section of the biodegradable microneedle having the central axis, the second step portion has a contacting end for forming a microneedle tip, the contacting end is arranged away from the first step portion and has an angle within a range of 65-100 degrees, and the contacting end has an arced surface having a diameter within a range of 10-25 μm.

A biodegradable microneedle of a microneedle structure defining a central axis, comprising:

• a first step portion;
• and
• a second step portion taperedly extending from the first step portion along the central axis,
• wherein the biodegradable microneedle has a total height along the central axis and a maximum internal diameter along a direction perpendicular to the central axis, wherein the total height is within a range of 350-430 μm, and an aspect ratio defined by the total height divided by the maximum internal diameter is within a range of 1.2-5.0, wherein in a cross section of the biodegradable microneedle having the central axis, the second step portion has a contacting end for forming a microneedle tip, the contacting end is arranged away from the first step portion and has an angle within a range of 65-100 degrees.