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Related Experiment Video

Updated: Jan 25, 2026

Polymeric Microneedle Array Fabrication by Photolithography

Polymeric Microneedle Array Fabrication by Photolithography

Published on: November 17, 2015

Design rules for a tunable merged-tip microneedle.

Jungeun Lim^1,2, Dongha Tahk^1,2,3, James Yu⁴

¹1School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, 08826 South Korea.

Microsystems & Nanoengineering

|May 7, 2019

Summary

This summary is machine-generated.

Researchers developed a novel microneedle platform using elasto-capillarity-driven self-assembly. This technique creates intricate merged-tip microneedles from biocompatible polymers for advanced transdermal drug delivery.

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Area of Science:

Biomaterials Science
Microfabrication
Nanotechnology

Background:

Microneedle platforms are crucial for transdermal drug delivery.
Existing fabrication methods often involve complex micromolding or micromachining.
There is a need for simpler, more versatile microneedle fabrication techniques.

Purpose of the Study:

To propose and investigate elasto-capillarity-driven self-assembly for fabricating microneedle platforms.
To develop a novel merged-tip microneedle microstructure with enhanced functionalities.
To establish design rules for customizable microneedle arrays.

Main Methods:

Utilized elasto-capillarity-driven self-assembly with biocompatible UV-curable polymers.
Combined self-assembly with photolithography for fabricating micropillar arrays.
Explored variations in micropillar dimensions, shapes, configurations, and materials.

Main Results:

Successfully fabricated a microscale merged-tip structure without micromolding or micromachining.
The merged-tip microstructure features a sharp tip and an open cavity for liquid trapping and volume control.
Demonstrated tunability of cavity volumes, fracture points, and merge profiles through design rule manipulation.
Investigated a modular base for payload delivery and fluid sampling.

Conclusions:

Elasto-capillarity-driven self-assembly offers a facile and flexible method for producing complex microneedle structures.
The novel merged-tip microneedle platform shows significant promise for transdermal drug delivery applications.
Customizable microneedle arrays can be achieved by controlling fabrication parameters.