Manganese Metal–Organic Framework: Chemical Stability, Photoluminescence Studies, and Biosensing Application

Abstract

Innovative diagnostic tools, new approaches, and novel methodologies for monitoring and quantification of biological biomarkers have become a dominant challenge. In this work, a novel fast, facile, accurate, selective, and ultra-sensitivity optical approach for troponin I (cTn) cardiac biomarker. cTn, is used as an early diagnostic test for the patients of myocardial infarction. It can support the accurate decisions in the absolute necessity cases. Herein, a manganese metal–organic framework “Mn-MOF” was synthesized via a facile route. The structural and morphology of the produced MOF was confirmed using several tools of characterizations. The chemical stability and photoluminescence (PL) studies of the Mn-MOF were investigated to elucidate the availability of using Mn-MOF as optical biosensor for cTn. Mn-MOF exhibited a characteristic photoluminescence (PL) emission (λem = 422 nm) that was blue-shifted and encountered a remarkable reduction in intensity in presence of cTn (i.e., PL quenching agent). According to Stern-Volmer equation, a linear [cTn]-quenching relationship was observed over a wide concentration range of cTn (1.0 fg- 30.0 pg/mL) and linear range between 1.0 fg and 0.025 ng/mL. The limit of quantitation (LOQ) and detection (LOD) for the method ware estimated to be 30.0 fg/mL and 10.0 fg/mL, respectively. Based on the present optical approach; the Mn-MOF can be used successfully as a cTn-biosensor in biological samples, even the presence of different interfering analytes. The mechanism of quenching was studied, and the results revealed that the dynamic type was achieved.