Microneedles (MNs) are playing an increasingly important role in biomedical applications, where minimally invasive methods are being developed that require imperceptible tissue penetration and drug delivery. To improve the integration of MNs in microelectromechanical devices, a high‐resolution 3D printing technique is implemented. A reservoir with an array of hollow MNs is produced. The flow rate through the MNs is simulated and measured experimentally. The mechanical properties of the 3D printed material, such as elasticity modulus and yield strength, are investigated as functions of printing parameters, reaching maximum values of 1750.7 and 101.8 MPa, respectively. Analytical estimation of the MN buckling, fracture, and skin penetration forces is presented. Penetration tests of MNs into a skin‐like material are conducted, where the piercing force ranges from 0.095 to 0.115 N, confirming sufficient stability of MNs. Furthermore, 200 and 400 μm‐long MN arrays are used to successfully pierce and deliver into mouse skin with an average penetration depth of 100 and 180 μm, respectively. A biocompatibility assessment is performed, showing a high viability of HCT 116 cells cultured on top of the MN's material, making the developed MNs a very attractive solution for many biomedical applications.

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Precision farming has the potential to increase global food production capacity whilst minimizing traditional inputs. However, the adoption and impact of precision farming are contingent on the availability of sensors that can discern the state of crops, while not interfering with their growth. Electrical impedance spectroscopy offers an avenue for nondestructive monitoring of crops. To that end, it is reported on the deployment of impedimetric sensors utilizing microneedles (MNs) that can be used to pierce the waxy exterior of plants to obtain sensitive impedance spectra in open‐air settings with an average relative noise value of 3.83%. The sensors are fabricated using a novel micromolding and release method that is compatible with UV photocurable and thermosetting polymers. Assessments of the quality of the MNs under scanning electron microscopy show that the replication process is high in fidelity to the original design of the master mold and that it can be used for upward of 20 replication cycles. The sensor's performance is validated against conventional planar sensors for obtaining the impedance values of Arabidopsis thaliana. As a change is detected in impedance due to lighting and hydration, this raises the possibility for their widespread use in precision farming.

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A high‐resolution 3D printing technique is used to create a delivery platform with microneedles and reservoir in a single fabrication step, which enables customization of shape, dimensions, needle count, volume etc. The platform is biocompatible and its capabilities are evaluated by penetration and delivery into different layers of mouse skin. Further details can be found in the article number http://doi.wiley.com/10.1002/adem.201901358 by Jurgen Kosel and co‐workers.