Fluorescence Resonance Energy Transfer from Sulfonated Graphene to Riboflavin: A Simple Way to Detect Vitamin B₂

Abstract

We have prepared sulfonated graphene (SG) by diazonium coupling technique and it has been characterized by UV-vis absorption spectroscopy, Raman spectroscopy, electron microscopy, energy-dispersive spectroscopy (EDS), EDS elemental mapping, X-ray photoelectron spectroscopy (XPS), and FTIR spectroscopy. The photoluminescence (PL) property of SG at different pH (pH 4, 7, and 9.2) has been investigated and SG shows highest PL-intensity and quantum yield at pH 4 compared to those at higher pH and that of GO at pH 4. Due to the strong overlap between the emission spectrum of SG and absorption spectrum of riboflavin (RF, vitamin B2) at pH 4, it has been tactfully used as donor for the fluorescence resonance energy transfer (FRET) process. However, graphene oxide (GO) does not exhibit any FRET with RF at an identical condition due to its much lower quantum yield. We have demonstrated a selective detection of vitamin B2 in presence of nucleic acid (DNA, RNA), protein (BSA), amino acid (Lysine) and other water-soluble vitamins (Becosules, Zevit capsules) based on the spontaneous FRET from PL-active SG (donor) to RF (acceptor). The calibration curve indicates excellent affirmation to detect vitamin B2 using FRET and it is superior to the ordinary fluorescence method of detecting RF in presence of different biomolecules.

Triarylamine‐Cored Dendritic Molecular Gel for Efficient Colorometric, Fluorometric, and Impedometeric Detection of Picric Acid

“…We calculated the LOD of PA for the OGR assembly from the resistance data by taking the OGR concentration (10 −7 m ), measuring the resistances from the Nyquist plots (Figure S14a in the Supporting Information), and plotting the percentage decrease in resistance against the PA concentration (Figure S14b in the Supporting Information). The LOD was calculated from 3×(SD) Blank / S , where SD is the standard deviation of the background resistance (i.e., in absence of nitroaromatics) and S the slope of the calibration curve (Figure S14b in the Supporting Information), and the LOD value was calculated to be 2.8×10 −10 M , which is very similar to that obtained from the fluorescence study. The resistance and capacitance values obtained with the software are listed in Table S5 of the Supporting Information.…”

“…The limits of detection (LOD) of different nitroaromatics for OGR aggregate in octanol (Table ) was determined from the photoluminescence intensity (Figures S6 and S7 in the Supporting Information) by using the formula LOD=3×(SD) Blank / S , where SD is the standard deviation of the background fluorescence (in the absence of nitroaromatics) and S the slope of the calibration curve (Figures S8 and S9 in the Supporting Information). The (SD) Blank value was measured to be 0.00843.…”

Characterization of flavin binding in oxygen‐independent fluorescent reporters

“…These methods, while widely used, suffer from limitations such as slow response, interference from other components in complex mixtures, and limited scalability to a medium or high throughput format. Fluorescent sensors can overcome many of these challenges, which has prompted the development of riboflavin sensors based on Förster Resonance Energy Transfer (FRET) between riboflavin and doped carbon dots 59 or graphene 60 as well as quenching of fluorescence using PEG‐dispersed graphene 61 . However, to our knowledge, a fluorescence “turn‐on” biosensor for riboflavin has not been reported.…”

Fabrication of riboflavin electrochemical sensor based on homoadenine single-stranded DNA/molybdenum disulfide–graphene nanocomposite modified gold electrode

“…The results denoted that the electrochemical behavior of riboflavin at the modified electrode was significantly improved possibly because rMoS 2 -graphene had high surface area and accelerated the electron-transfer kinetics. Simultaneously, the reason for the negative shift of the redox peak potentials very likely contributed to the relatively strong interactions of some functional groups at the rMoS 2 -graphene surface toward riboflavin [42][43][44][45][46]. Correspondingly, the DPV measurements at the three electrodes (Fig.…”