3D Matter Made to Order

On September 30, 2025, our members gathered at the University of Heidelberg for this year’s Summer Cluster Meeting. The program included a general assembly with an overview of the upcoming 3DMM2O Conference 2026: Frontiers in Theory, Computation, and Design of 3D Materials, as well as scientific presentations. A newly introduced interactive smartboard session offered a dynamic way to exchange ideas across research areas. During coffee breaks, lively discussions continued, bringing fresh perspectives to the day. The focus was on the structures and projects of the second funding period, providing common ground for discussion and planning. The meeting also offered opportunities for networking and informal exchanges, strengthening connections within the community. It concluded with a sense of collaboration and excitement for the projects ahead.

A new study by Cluster Doctoral Researchers Chantal Barwig, Malin Schmidt, Annabelle Sonn, Scientist Irene Wacker, as well as Principal Investigators Rasmus R. Schröder and Christine Selhuber-Unkel, explores a new type of microscale actuator made from soft, responsive hydrogels. These actuators can switch between two stable states without continuous energy input, a property known as bistability. The team created 3D microstructures that can be precisely controlled using two-photon polymerization by combining thermoresponsive and light-responsive components. This innovation opens new opportunities for energy-efficient soft robotics, biomedical applications, and reconfigurable microfluidic systems.

©Barwig et al., Adv. Intell. Syst. 2025, CC BY

From September 7–11, the HEiKA Summer Science Academy 2025 brought together master’s and final-year bachelor’s students at the Bildungshaus St. Bernhard in Rastatt. The academy was organized by the Heidelberg-Karlsruhe Strategic Partnership HEiKA in partnership with our Cluster 3DMM2O and the Flagship Initiative Engineering Molecular Systems of Heidelberg University. Participants attended hands-on workshops led by top researchers who covered topics such as biofabrication, responsive materials, stem cell dynamics, cancer evolution, and 3D lithography. The program provided a unique, immersive experience that fostered collaboration, exchange, and innovation at the intersection of molecular systems and 3D engineering.

A new study, including Cluster Doctoral Researchers Maike Schliephake and Yan Liu and PIs Prof. Dr. Jasmin Aghassi-Hagmann and Prof. Dr. Pavel Levkin, explores the use of fluorescent metal-organic framework (MOF) thin-film arrays as surface-based sensors. They created stable, easy-to-use devices by directly patterning fluorescent dyes onto flat MOF films, overcoming the drawbacks of MOF suspensions. These arrays can track pH levels within the biological range (5–9) and detect disease-related molecules, such as dopamine. Their robust design enables multiplexed measurements and integration into lab-on-a-chip systems, creating opportunities in healthcare, environmental monitoring, and food safety.

© Wang et al., Small 2025, CC BY

A new study in Communications Materials — including Cluster Postdoctoral Researcher Nils Rosemann and Principal Investigators Jasmin Aghassi-Hagmann and Stefanie Dehnen — demonstrates the first successful inkjet printing of adamantane-type organotin sulfide clusters without altering their molecular identity. These clusters exhibit unusual optical properties, producing either white light or frequency doubling depending on their structure. The researchers overcame the longstanding challenges of instability and poor solubility by combining phenyl groups, which improve optical performance, with alkyl chains, which improve solubility. This breakthrough paves the way for printable, reusable, and thermally stable optical data storage materials.

© Nier et al., Communications Materials, 2025, CC BY 4.0

A recent study, including Cluster Doctoral Researcher Alexander Berkes, Alumnus Pascal Kiefer and PI Martin Wegener, explores how the geometry of carrier particles affects drug delivery in dry powder inhalers. The team used multi-photon 3D laser printing to create millions of microparticles with different shapes and surface textures. The spiked Pharmacone design performed best, enabling the highest fraction of respirable drug particles. Although these particles are not intended for inhalation, this approach suggests the possibility of future biocompatible, precision-engineered carriers for more effective lung therapies.

© Wostry et al., Communications Materials 2025, CC BY 4.0