Institute of Biomaterials and Biomedical Engineering, University of Toronto, ON, M5G 1L7, Canada.
Biomacromolecules. 2011 Sep 12;12(9):3115-8. doi: 10.1021/bm200784s. Epub 2011 Jul 26.
We demonstrate that porphyrins can be used as efficient cross-linkers to generate a new class of hydrogels with enabling optical properties. Tetracarboxylic acid porphyrins reacted with PEG diamines to form a condensation polyamide in a range of appropriate conditions, with respect to reaction time, diisopropylethylamine initiator concentration, porphyrin-to-PEG ratio, porphyrin concentration, and PEG size. The network structure of the hydrogel maintained a porphyrin spacing that prevented excessive fluorescence self-quenching despite high porphyrin density. The near-infrared properties readily enabled low background, noninvasive fluorescence monitoring of the implanted hydrogel in vivo, as well as its image-guided surgical removal in real time using a low-cost fluorescence camera prototype. Emission could be tuned by incorporating copper metalloporphyrins into the network. The approach of creating hydrogels using cross-linking porphyrin comonomers creates opportunities for new polymer designs with strong optical character.
我们证明了卟啉可以作为有效的交联剂，生成具有光学性能的新型水凝胶。四羧酸卟啉与 PEG 二胺反应，在适当的条件下（反应时间、二异丙基乙胺引发剂浓度、卟啉与 PEG 的比例、卟啉浓度和 PEG 大小）形成缩聚酰胺。水凝胶的网络结构保持了卟啉的间距，尽管卟啉密度很高，但防止了荧光自猝灭。近红外性质使得能够在体内对植入的水凝胶进行低背景、非侵入性荧光监测，并使用低成本荧光相机原型实时进行图像引导的手术切除。通过将铜金属卟啉掺入网络中，可以调整发射。使用交联卟啉共聚单体来制造水凝胶的方法为具有强光学特性的新型聚合物设计创造了机会。
