School of Chemistry and Chemical Engineering, Jinggangshan University, Ji'an, Jiangxi 343009, China.
School of Medicine, Taizhou University, Taizhou, Zhejiang 318000, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Mar 5;268:120662. doi: 10.1016/j.saa.2021.120662. Epub 2021 Nov 26.
Ring-opening reaction of rhodamine spirolactam has been widely applied to construct fluorescent probes. The fluorescence properties of the probe were finely tuned for specific purpose through changing the rhodamine fluorophore. However, the influence on response range and kinetic parameters of the probe during the change has been seldom discussed. Herein, we took pH detection as an example and constructed spirolactam based probes (RLH A-C) with Rhodamine 6G, Rhodamine B and Rhodamine 101. The pK values and observed rate constant k of RLH A-C were determined and found to negatively correlated with the calculated Gibbs free energy differences ΔG and ΔG respectively. The potential applications of RLH A-C in imaging acidic microenvironment were also investigated in cells. We expect the comparison of rhodamine fluorophores will facilitate the quantitative optimization of rhodamine spirolactam based fluorescent probes.
螺环吲哚酮的开环反应已广泛应用于构建荧光探针。通过改变罗丹明荧光团，可以精细调节探针的荧光性质，以满足特定目的。然而，在这种改变过程中，对探针的响应范围和动力学参数的影响却很少被讨论。在此，我们以 pH 检测为例，构建了以 Rhodamine 6G、Rhodamine B 和 Rhodamine 101 为荧光团的螺环吲哚酮探针（RLH A-C）。测定了 RLH A-C 的 pK 值和观察到的速率常数 k，发现它们与计算的吉布斯自由能差 ΔG 和 ΔG 分别呈负相关。还研究了 RLH A-C 在细胞内成像酸性微环境中的潜在应用。我们期望对罗丹明荧光团的比较将有助于定量优化基于罗丹明螺环吲哚酮的荧光探针。
