Page 132 - IJB-8-2

RESEARCH ARTICLE

Fast Customization of Hollow Microneedle Patches for

Insulin Delivery

Rong Li , Xuan Liu , Xin Yuan , Shanshan Wu , Li Li , Xuebing Jiang , Bo Li , Xian Jiang ,
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Maling Gou *
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1 State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, China
2 Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, 610041, China
3 Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
Abstract: Hollow microneedle patches (HMNPs) have great promise for efficient and precise transdermal drug delivery in a
painless manner. Currently, the clinical application of HMNPs is restricted by its complex manufacturing processes. Here, we
use a new three-dimensional (3D) printing technology, static optical projection lithography (SOPL), for the fast fabrication
of HMNPs. In this technology, a light beam is modulated into a customized pattern by a digital micromirror device (DMD)
and projected to induce the spatial polymerization of monomer solutions which is controlled by the distribution of the light
intensity in the monomer solutions. After an annulus picture is inputted into the DMD via the computer, the microneedles
with hollow-cone structure can be precisely printed in seconds. By designing the printing pictures, the personalized HMNPs
can be fast customized, which can afford the scale-up preparation of personalized HMNPs. Meanwhile, the obtained hollow
microneedles (HMNs) have smooth surface without layer-by-layer structure in the commonly 3D-printed products. After
being equipped with a micro-syringe, the HMNPs can efficiently deliver insulin into the skin by injection, resulting in effective
control of the blood glucose level in diabetic mice. This work demonstrates a SOPL-based 3D printing technology for fast
customization of HMNPs with promising medical applications.

Keywords: Microneedle; Three-dimensional printing; Hollow microneedle patches; Fabrication; Drug delivery

*Correspondence to: Maling Gou, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu,
610041, China; goumaling@scu.edu.cn

Received: January 24, 2022; Accepted: March 8, 2022; Published Online: March 8, 2022
Citation: Li R, Liu X, Yuan X, et al., 2022, Fast Customization of Hollow Microneedle Patches for Insulin Delivery. Int J Bioprint, 8(2):553.
http://doi.org/10.18063/ijb.v8i2.553

1. Introduction used to destroy the skin cell structures and induce the
expression and deposition of elastin and collagen. Coated
Microneedles are micron-sized needles, capable of microneedles deliver the drugs coated on the surface of
perforating stratum corneum painlessly and delivering microneedles into the skin. Dissolving microneedles are
drugs into the body. The primary superiority of made of dissolvable materials and release the drugs after
microneedles is that they combine the potential microneedle dissolution. Porous microneedles release the
delivery ability of a hypodermic needle with the user- drug into the skin through the pores of the needle body,
friendly benefits of a percutaneous patch. Based on the such as swelling hydrogel-forming microneedle , and
[1]
application characteristics of microneedles, they can be other porous microneedles [2-4] . HMNs can be regarded
divided into solid microneedles, coated microneedles, as scaled-down traditional hypodermic needles with a
dissolving microneedles, porous microneedles, and micron-level length and diameter. When connected to
hollow microneedles (HMNs). The pretreatment of a syringe or device, they have the potential to replace
skin with solid microneedles in advance promotes the syringe-based administration that usually causes fear
permeation of transdermal preparations (e.g., ointments, in the user. Compared with the other four types of
gels, and emulsions). Solid microneedles can also be microneedles, HMNs have major advantages, such as

© 2022 Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution License, permitting distribution and
reproduction in any medium, provided the original work is properly cited.
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