Label-free detection of creatinine using nitrogen-passivated fluorescent carbon dots

• DOI: 10.1039/d0ra06512a
• Publication Date: 2020-10-01T14:01:08Z
• Authors: Shagun Kainth; Banibrata Maity; Soumen Basu
• Keywords: Carbon fibers

In the field of biochemistry and biosensing, passivation carbon dots using nitrogen dopants has attracted great attention, as this can control their photoluminescence (PL) properties quantum yield. To date, in fabrication a sensing probe, impact chemical composition passivating molecule remained unexplored. work, we chose series different nitrogen-rich precursors (such urea, thiourea, cysteine, glycine) ascorbic acid to synthesize nitrogen-doped (NCDs). A significant change surface states was obtained due evolution variable contents amino, pyridinic pyrrolic species, which is evident from X-ray photoelectron spectroscopy, leads an increment PL yields (PLQY ∼ 58%) average lifetime values. Spectroscopic analysis revealed that rise ratio : amino groups on cause bathochromic shift generate excitation-dependent NCDs. Besides, these NCDs were used fluorescence off-on probes, where PA-infested NCD solution detect creatinine. Chiefly, restoration achieved formation Jaffe chromogen between creatinine PA. However, all nitrogen-passivated dot surfaces do not respond similarly towards only non-amino-rich exhibit maximum (50%) turn-on response. The turn-off-on methodology showed satisfactory good linearity range 0 150 μM with detection limit 0.021 nM for Three input molecular logic gates also designed based response NCDs@PA Additionally, analytical method validation, real-sample performed creatinine, recoveries (93-102%) verified tailored physicochemical enhanced ability.