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Biology subjects

Gurtner, G.

Publications and source records attributed to Gurtner, G..

3 recordsLinked to original sources

Topological supramolecular network enabled highly conductive and stretchable organic bioelectronics

Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. However, the grand challenge remains for the conducting polymer to possess both high mechanical ductility and good electrical conduction at cellular level feature sizes. This longstanding material limitation in organic bioelectronics has impeded the full exploitation of its unique benefits. Here, we introduce a new molecular engineering strategy based on rationally designed topological supramolecular networks, which allows effective decoupling of competing effects from multiple molecular building blocks to meet complex requirements. We achieve two orders of magnitude improvement in the conductivity under 100% strain in physiological environment, along with the capability for direct photopatterning down to 2 m. These unprecedented capabilities allow us to realize previously inaccessible bioelectronic applications including high-resolution monitoring of soft and malleable creatures, e.g., octopus, and localized neuromodulation down to single nucleus precision for controlling organ-specific activities through delicate tissues, e.g., brainstem.

bioengineering↗

Wireless closed-loop smart bandage for chronic wound management and accelerated tissue regeneration

Chronic non-healing wounds represent a major source of morbidity for patients and a significant economic burden. Current wound care treatments are generally passive and are unable to adapt to changes in the wound environment in real time. By integrating multimodal sensors and adding stimulators in a bandage, real-time physiological monitoring is possible and provides an opportunity for active intervention into the complex wound environment. Here, we develop a battery-free flexible bioelectronic system consisting of wirelessly powered, closed-loop sensing and stimulation circuits with tissue-interfacing tough conducting hydrogel electrodes for robust signal transduction, on-demand adhesion, and detachment. Using multiple pre-clinical models, we demonstrate the capability of our wound care system to continuously monitor skin impedance and temperature, to trigger directional electrical stimulation. The accelerated wound closure was confirmed to be due to the activation of pro-regenerative genes linked to accelerated wound closure, increased neovascularization, and enhanced dermal recovery.

bioengineering↗

Endothelial CXCL12 regulates neovascularization during tissue repair and tumor progression

CXC chemokine ligand 12 (CXCL12; stromal cell-derived factor 1 [SDF-1]), primarily known for its role in embryogenesis and hematopoiesis, has also been implicated in tumor biology and neovascularization. However, its specific role and mechanism of action remain poorly understood. We previously demonstrated that CXCL12 expression is Hypoxia-Inducible Factor (HIF)-1 responsive. Here we use a conditional CXCL12 knockout mouse to show that endothelial-specific deletion of CXCL12 (eKO) does not affect embryogenesis, but reduces the survival of ischemic tissue, altering tissue repair and tumor progression. Loss of vascular endothelial CXCL12 disrupts endothelial - fibroblast crosstalk necessary for stromal growth and vascularization. Single-cell gene expression analysis in combination with a parabiosis model reveals a specific population of non-inflammatory circulating cells, defined by genes regulating neovascularization, which is recruited by endothelial CXCL12. These findings indicate an essential role for endothelial CXCL12 expression during the adult neovascular response in tissue injury and tumor progression.

molecular biology↗