Determination of urinary N-acetylneuraminic acid for early diagnosis of lung cancer by a boric acid covalently functionalized lanthanide MOFs and its intelligent visual molecular robot application

In this work, a boric acid covalently functionalized lanthanide MOF (Ln-MOF) sensor was constructed for the first time to monitor of urinary N-acetylneuraminic acid (NANA) to early diagnose of lung cancer, NANA can be used as biomarker of lung cancer. Considering that the specific binding affinity between boronic acid group and cis-diol can probably cause special influence towards the fluorescence of Ln-MOF, a boric-acid-functionalized Ln-MOF (B-EuMOF) sensor was first designed by covalent modification, which is proved to be an effective ratiometric fluorescent sensor of NANA, a urinary biomarker of lung cancer containing cis-diol. This designed NANA sensor shows special enrichment capacity, high selectivity and sensitivity, fast response, excellent reusability and more important, the ratiometric sensing result can be clearly distinguished by naked eye. Based on the luminescent sensing property of B-EuMOF towards NANA and the capture function of boric acid group, a molecular robot system which can monitor lung cancer at early stage is constructed. In this molecular robot system, boronic acid group serves as the actuator using ‘functional-hand’ to grasp NANA for the molecular robots. The fluorescence of B-EuMOF (I 470 nm /I 614 nm ) act as the sensor of the molecular robots. And the processor is constructed by combinational logic gates (INHIBIT and AND) which can control the molecular robots by logical operation of fluorescence response of B-EuMOF towards NANA. This work proposes first example of Ln-MOFs based molecular robot and what’s more, paves new way for the combination of fluorescent sensor and intelligent molecular devices.