Synthesis of green fluorescent carbon dots using cysteine and maltose as ecofriendly ligands for the detection of venlafaxine anti-depression drug in pharmaceutical and plasma samples
Vibhuti Atulbhai Sadhu, Tae Jung Park, Suresh Kumar Kailasa
Abstract
In this work, the green emissive carbon dots (CDs) were fabricated using cysteine and maltose as bio-precursors via refluxing process. The emission and excitation peaks of fabricated cysteine-maltose CDs (CM-CDs) are noticed at 511 and 420 nm, respectively. The as-fabricated CM-CDs displayed average mean size of 3.63 ± 1.12 nm with uniform spherical shape and good quantum yield of 32.81 %. Importantly, the as-fabricated CM-CDs act as a sensor for venlafaxine an anti-depression drug sensing via a fluorescence “turn-off” mechanism. The fluorescence lifetime of CM-CDs was 1.34 ns. The as-fabricated CM-CDs were highly sensitive towards venlafaxine, displaying good linear range from 0.1 to 180 µM with the limit of detection of 75.15 nM. The fluorescence of CM-CDs was reduced with the interaction of venlafaxine, thereby favoring to develop CM-CDs-based cellulose paper sensor for venlafaxine assay. The fabricated sensor was effectively utilized for the quantification of venlafaxine in pharmaceutical and biological samples with good recovery rates (96.01––99.65 %).