Coordination-driven supramolecular hydrogels feature excellent processability and dynamic responsibility and thus are appealing for applications such as biomedical photonics. Since they are constructed via hierarchical assembly, the gelation processes are difficult to control in a highly efficient manner, leading to limited transparency. For the formation of hydrogel, stepwise introduction of water is essential for the gelation. Phosphorescence with high H₂O sensitivity can be explored for in situ monitoring and precise understanding of the gelation process. Herein, a hydrogel from Gd³⁺-adenosine monophosphate (AMP) assembly was chosen as the model, which was formed via the strong Gd³⁺-PO3 coordination and π–π stacking of A bases. On the basis of the excellent guest inclusion and phosphorescence inducing of the Gd³⁺-AMP matrix, thioflavin-T (ThT, cyan fluorescence) and Pt(II) meso-tetra(4-carboxyphenyl) porphine (PtTCPP, red phosphorescence) were coencapsulated as the probe. Via the luminescence changes, the gelation process was visualized, and two kinds of cloudy side products (NPs and sol, indistinguishable to the naked eye) were identified. Further calorimetric investigation on the above cloudy side products allowed for improvement of the transparency of the hydrogel by changing the synthesis temperature. The obtained flexible and transparent room-temperature phosphorescence (RTP) hydrogel was explored for implantable optical waveguide-based oxygen sensing.

中文翻译：

---

凝胶化中动态配位驱动组装的基于磷光的可视化


配位驱动的超分子水凝胶具有出色的加工性能和动态性能，因此适用于生物医学光子学等应用。由于它们是通过分层组装构建的，因此难以以高效方式控制凝胶化过程，从而导致透明度有限。为了形成水凝胶，逐步引入水对于凝胶化至关重要。可以探索具有高 H₂O 灵敏度的磷光，用于原位监测和精确了解凝胶化过程。在此，选择来自 Gd³⁺-腺苷一磷酸 （AMP） 组装体的水凝胶作为模型，其是通过 A 碱基的强 Gd³⁺-PO3 配位和 π-π 堆叠形成的。在 Gd³⁺-AMP 基质优异的客体包涵和磷光诱导的基础上，硫黄素-T （ThT，青色荧光） 和 Pt（II） 内消旋四（4-羧基苯基）卟啉 （PtTCPP，红色磷光） 作为探针被共封装。通过发光变化，可以看到凝胶化过程，并鉴定出两种混浊的副产物 （NPs 和 sol，肉眼无法区分）。对上述浑浊侧产物的进一步量热研究允许通过改变合成温度来提高水凝胶的透明度。探索了所获得的柔性透明室温磷光 （RTP） 水凝胶，用于基于植入式光波导的氧传感。