ABSTRACT
A water stable one-dimensional (1D) ladder-shaped coordination polymer (CP) has been synthesized and exhibits a strong affinity to two fluorescein-tagged single-stranded probe DNAs (P-DNAs), giving a sensing platform of P-DNAs@1. Such a hybrid sensing platform is capable of simultaneous detection of breast cancer related microRNA-221 (miRNA-221) and miRNA-222 in a specific and synchronous manner, without observable cross-reactions, as supported by experimental evidences. The interaction mode and the electronic energy between CP 1 with nucleic acid were confirmed by molecular simulation and the universal force field (UFF).
Subject(s)
Coordination Complexes/chemistry , DNA/chemistry , MicroRNAs/antagonists & inhibitors , MicroRNAs/analysis , Molecular Dynamics SimulationABSTRACT
We report herein five sensing platforms for the detection of five gastric cancer associated microRNAs (miRNAs). The sensing platforms are hybrids formed from a water-stable metal organic framework (MOF) {[Cu(dcbb)2(H2O)2]·10H2O}n (1, H2dcbbBr=1-(3,5-dicarboxybenzyl)-4,4'-bipyridinium bromide), respectively with five carboxyfluorescein (FAM) labeled probe single-stranded DNA (probe ss-DNA, denoted as P-DNA). Within the hybrid, MOF 1 tightly interacts with the P-DNA through electrostatic and/or π-stacking interactions and results in fluorescence quenching of FAM via a photo-induced electron transfer (PET) process. In the presence of the complementary target miRNAs miR-185, miR-20a, miR-92b, miR-25 and miR-210, which are expressed abnormally in the plasma of gastric carcinoma patients, P-DNA is released from the surface of MOF 1 ascribed to the stronger base pair matching, leading to the FAM fluorescence recovery. Each P-DNA@1 system is effective and reliable for the detection of its complementary target miRNA with the detection limits from 91 to 559pM, and is not interfered by other four miRNA sequences.
