3D-Printed Hollow Microneedles Array with Luer Lock Connection for Facile and Painless Intradermal Injection: A Proof of Concept

A 3D-printed array of hollow microneedles (HMNs) is designed and fabricated using a high-resolution stereolithography 3D printer and assembled with a 3D-printed reservoir that incorporates a Luer lock mechanism, ensuring standard and secure connection to syringes. The proof-of-concept needle designs consist of half-eccentric and concentric conical tip shapes, each arrayed with two different interspacing values. After the geometrical features of the devices are characterized, the devices are tested ex vivo in porcine skin to evaluate the impact of tip shape and interspacing on the depth of penetration and the efficacy of the devices in delivering fluids (such as tattoo ink) into the dermis. Overall, the 3D-printed HMNs can deliver fluids into the target layer of skin. Refinement of the design is ongoing with the ultimate aim to provide alternatives for intradermal drug delivery and diagnostic imaging, such as superficial lymphography. A proof-of-concept 3D-printed array of hollow microneedles (HMNs) is designed and fabricated using a high-resolution stereolithography 3D printer and assembled with a 3D-printed reservoir that incorporates a Luer lock mechanism, ensuring standard and secure connection to syringes. The ultimate aim of using this device is to provide alternatives for intradermal drug delivery and diagnostic imaging, such as superficial lymphography. image