Molecular sieving of L-arginine over L-lysine by -Hydroxy acid functionalized Zn^II-luminescent framework from aqueous medium and other biofluids: Experimental and DFT corroboration with logic gate construction

The present work exemplifies MOF as a unique functional scaffold for ultrasensitive monitoring of L-Arginine (Arg) over L-Lysine (Lys) and other amino acids from purely aqueous medium. In this context, a thermostable Zn-II-functionalized MOF (viz. Zn-II-CA-LMOF) has been synthesized utilizing alpha-hydroxy acid containing aliphatic ligand like citric acid (CA). The MOF provides an excellent platform for optical speciation of Arg over other competitive biohazards via "turn-on" fluorescence response with a limit of detection 3.3 ppb (R = 0.99) with response time of similar to 90 s. Interestingly, the Zn-MOF has been exploited for detecting Arg from complex bio-fluids which are of immense clinical importance. Additionally, DFT studies shed light on the role of SBUs in noncovalent interaction between CA and targeted bio-hazards in a confined space which results in desired molecular sieving amongst different bio-analytes. Moreover, the host-guest interactions through "turn-off-on-off" have been utilized for fabricating molecular electronics. In brief, the demand of formulizing a single platform to rationalize the structure-performance synergies to fabricate smarter material has been properly emphasized in the current work.