The employment of an ancillary amine-substituted bisphosphonate ligand affords a dicobalt complex able to quantitate pH with a remarkably high sensitivity of 8.8(5) pH unit⁻¹ at 37 °C through a ratiometric paramagnetic chemical exchange saturation transfer (PARACEST) approach, where the different pH dependences of amine and amide CEST peak intensities are utilized.

中文翻译：

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通过双甲双胍PARACEST探针的配体修饰，pH灵敏度和信号强度显着提高†

采用辅助胺取代的双膦酸酯配体可提供一种二甲双酚络合物，该化合物能够通过比例顺磁化学交换饱和转移（PARACEST）方法在37°C下以8.8（5）pH单位^-1的极高灵敏度定量pH。利用了胺和酰胺CEST峰强度的不同pH依赖性。