Lanthanum-Based Metal–Organic Frameworks for Specific Detection of Sudan Virus RNA Conservative Sequences down to Single-Base Mismatch

Abstract

Reactions of La(NO)·6HO with the polar, tritopic quaternized carboxylate ligands N-carboxymethyl-3,5-dicarboxylpyridinium bromide (HCmdcpBr) and N-(4-carboxybenzyl)-3,5-dicarboxylpyridinium bromide (HCbdcpBr) afford two water-stable metal-organic frameworks (MOFs) of {[La(Cmdcp)(HO)]} (1, 3D) and {[La(Cbdcp)(HO)]} (2, 2D). MOFs 1 and 2 absorb the carboxyfluorescein (FAM)-tagged probe DNA (P-DNA) and quench the fluorescence of FAM via a photoinduced electron transfer (PET) process. The nonemissive P-DNA@MOF hybrids thus formed in turn function as sensing platforms to distinguish conservative linear, single-stranded RNA sequences of Sudan virus with high selectivity and low detection limits of 112 and 67 pM, respectively (at a signal-to-noise ratio of 3). These hybrids also exhibit high specificity and discriminate down to single-base mismatch RNA sequences.

Metal-organic frameworks for virus detection

“…They are good candidates for sensing virus owing to their high coordination number and high lipophilicity to make structurally intriguing and water-stable MOFs. The fluorescence quenching properties of La 3+ (79.8 ± 6.4%) endow La-MOF with applications for detecting the Sudan virus ( Yang et al, 2017 ), and the performance was consistent with other transition metals ( Yang et al, 2015 ; Zhu et al, 2013 ). Besides, indium is also favored due to its integrating cationic functionality (NMe 3+ ) and aromaticity, as well as non-toxicity ( Li et al, 2016 ).…”

“…Enhanced π-π interactions can be achieved by introducing ligands or auxiliary ligands in a planar structure, or synthesizing 2D multifunctional MOF nanosheets ( Li et al, 2019c ). As for hydrogen bonding, some functional groups can be applied, such as –OH and –NH 2 ( Zhao et al, 2019a ), quaternary ammonium groups ( Wang et al, 2017 ; Yang et al, 2017 ), N-carboxymethyl-3,5-dicarboxylpyridinium bromide (H 3 CmdcpBr) ( Sun et al, 2017 ; Yang et al, 2015 ). And the structural matching between the probe DNA and MOFs should be taken into account in future MOF design ( Sun et al, 2017 ).…”

“… Interactions/Functions Ligands/functional groups/structures Refs. Electrostatic interactions Negatively charged phenolic hydroxyl and carboxyl groups on FAM; negatively charged phosphate backbones of P-DNA; cationic quaternary amines-decorated metal phthalocyanines, involving –SCH 2 CH 2 N(Me) 3 , –OCH 2 CH 2 N(Me) 3 and-SH 2 CH 2 N(Et) 3 , positively charged SYBR Green I (SGI), ; ; ( Guo et al, 2015 ; Ren et al, 2007 ; Sun et al, 2017 ; Wang et al, 2017 ; Xie et al 2018 , 2019 ; Yang et al 2015 , 2017 ; Zhao et al, 2016a ) Hydrogen bonding -NH 2 , UiO-66-NH 2 , –COOH, imidazolate ring, and carboxylates ( Wei, 2013 ; Zhang et al, 2014a ; Zhao et al, 2016a ) ( Cavka et al, 2008 ; Pan et al, 2018 ) π–π stacking ; ; ; ; ; ; ; ; ( Sun et al, 2017 ; Xie et al 2018 , 2019 ; Yang et al, 2015 ; Zhao et al, 2016a ) Water stabilities ; ; ; ; Zwitterionic thiolate ( Li et al, 2016 ; …”

“…(C) The schematic of lanthanum-based MOFs for specific detection of Sudan virus RNA conservative sequences. Reproduced with permission from ( Yang et al, 2017 ). Copyright 2017, American Chemical Society.…”

Two-dimensional nanomaterials for Förster resonance energy transfer–based sensing applications

“…The 2D MOF nanosheets have been widely used in the construction of FRET sensors in nanomedicine as they exhibit several advantages over other 2D nanomaterials such as high structural tunability and degradability [148][149][150][151][152][153]. In the study of Wang et al [149], the two-color intracellular adenosine imaging in living cells was achieved by using the lanthanide-based MOF nanosheets.…”