Departments of Biomedical Engineering and Chemical and Biological Engineering, 210 Bonner Hall, University at Buffalo, Buffalo, NY, 14260, USA.
Adv Healthc Mater. 2014 Jun;3(6):891-6. doi: 10.1002/adhm.201300483. Epub 2013 Nov 20.
Development of long-term implantable luminescent biosensors for subcutaneous oxygen has proved challenging due to difficulties in immobilizing a biocompatible matrix that prevents sensor aggregation yet maintains sufficient concentration for transdermal optical detection. Here, Pd-porphyrins can be used as PEG cross-linkers to generate a polyamide hydrogel with extreme porphyrin density (≈5 × 10(-3) m). Dye aggregation is avoided due to the spatially constraining 3D mesh formed by the porphyrins themselves. The hydrogel exhibits oxygen-responsive phosphorescence and can be stably implanted subcutaneously in mice for weeks without degradation, bleaching, or host rejection. To further facilitate oxygen detection using steady-state techniques, an oxygen-non-responsive companion hydrogel is developed by blending copper and free base porphyrins to yield intensity-matched luminescence for ratiometric detection.
由于难以固定生物相容性基质以防止传感器聚集同时保持足够的浓度进行透皮光学检测，因此开发可长期植入的皮下氧发光生物传感器一直具有挑战性。在这里，可以使用钯卟啉作为 PEG 交联剂来生成具有极高卟啉密度（≈5×10（-3）m）的聚酰胺水凝胶。由于卟啉本身形成的空间限制的 3D 网格，避免了染料聚集。水凝胶表现出氧响应的磷光，并且可以在没有降解、漂白或宿主排斥的情况下稳定地植入小鼠皮下数周。为了进一步利用稳态技术进行氧检测，通过混合铜和自由碱基卟啉来开发对氧无响应的伴生水凝胶，以产生用于比率检测的强度匹配的发光。
