Subcutaneous (SC) insulin injection has been demonstrated to be the most effective method for treatment of diabetes mellitus but is conventionally performed by hypodermic needles, leading to poor management of diabetes because of the pain, needle phobia, and tissue trauma. Identification of a viable, safe, and pain-free alternative method has been a longstanding challenge in modern health care. Here, the thermoplastic droplet stretching technique is developed to create an ultrahigh-aspect-ratio needle mold with simple microstructure control. The optimized ultrafine needle (UN) with 4 mm length, minimized 120 µm outer diameter, and 15° sharp bevel angle is formed via electroplating of a metallic layer on the surface of a needle mold with forcing sharp tip. This novel UN enables minimally invasive 4 mm skin insertion to deliver insulin in the targeted SC layer. The similar relative areas under the curves of insulin concentration within UN and 31G needle in vivo insulin administration indicate that UN can ensure stable insulin absorption for secure blood glucose management. Additionally, the proposed fabrication method may facilitate industrialization and commercialization of the UN, holding great promise for replacement of hypodermic needles and for improvement of quality of life among patients with diabetes.
Bibliographical noteFunding Information:
This work was supported equally by the R&D program of MSIP/COMPA (2015K000201, Development of minimal pain multi-micro lancets for one-touch smart diagnostic sensor), by Research Program to solve social issues of the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (Grant No. 2015073685), and by a grant from the National Research Foundation (NRF), the Translational Research Center for Protein Function Control (Grant No. 2016R1A5A1004694).
© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics