Wireless, implantable catheter-type oximeter designed for cardiac oxygen saturation.

Accurate, real-time monitoring of intravascular oxygen levels is important in tracking the cardiopulmonary health of patients after cardiothoracic surgery. Existing technologies use intravascular placement of glass fiber-optic catheters that pose risks of blood vessel damage, thrombosis, and infection. In addition, physical tethers to power supply systems and data acquisition hardware limit freedom of movement and add clutter to the intensive care unit. This report introduces a wireless, miniaturized, implantable optoelectronic catheter system incorporating optical components on the probe, encapsulated by soft biocompatible materials, as alternative technology that avoids these disadvantages. The absence of physical tethers and the flexible, biocompatible construction of the probe represent key defining features, resulting in a high-performance, patient-friendly implantable oximeter that can monitor localized tissue oxygenation, heart rate, and respiratory activity with wireless, real-time, continuous operation. In vitro and in vivo testing shows that this platform offers measurement accuracy and precision equivalent to those of existing clinical standards.

High throughput direct 3D bioprinting in multiwell plates.

Advances in three dimensional (3D) bioprinting have enabled the fabrication of sophisticated 3D tissue scaffolds for biological and medical applications, where high speed, high throughput production in well plates is a critical need. Here, we present an integrated 3D bioprinting platform based on microscale continuous optical printing, capable of high throughputin siturapid fabrication of complex 3D biomedical samples in multiwell plate formats for subsequent culture and analysis. Our high throughput 3D bioprinter (HT-3DP) was used to showcase constructs of varying spatial geometries of biomimetic significance, tunable mechanical properties, as well as reproducibility. Live hepatocellular carcinoma 3D tissue scaffolds were fabricatedin situin multiwell plates, after which a functional drug response assay against the chemotherapy drug doxorubicin was performed. Dual cell-type populations involving both live hepatocellular carcinoma as well as human umbilical vein endothelial cells were also printed to demonstrate dual-tissue fabrication capability. This work demonstrates a significant advancement in that the production rate of 3D bioprinted tissue scaffolds with controllable spatial architectures and mechanical properties can now be done on a high throughput scale, enabling rapid generation ofin vitro3D tissue models within conventional multiwell cell culture plates for high throughput preclinical drug screening and disease modeling.