MOF-Based Dual Sensor for the Electrochemical and Fluorescence Detection of Nicotine

Abstract

Detection of nicotine is highly desired; therefore, there is an endless need to develop multifunctional sensors that can detect nicotine in more than one way. Metal−organic frameworks, a class of porous hybrid materials known for their tunability, can be strong candidates for developing nicotine sensors. In this work, we have developed a pure Metal−organic framework (MOF)based dual sensor for the highly selective detection of nicotine. Interestingly, the sensor can efficiently detect nicotine using fluorescence and electrochemical sensing technique with a detection limit as low as 0.25 μM. Real cigarette and urine samples have been studied to evaluate the nicotine content in actual conditions where the sensor shows nearly 100% nicotine recovery. Selectivity experiments demonstrate that the MOF sensor can efficiently detect nicotine in the presence of other interfering analytes such as glucose, dopamine, and various metal salts. A plausible mechanism has been described for the MOFs' nicotine-sensing ability and Xray photoelectron spectroscopy (XPS) analysis shows that nicotine is present in the MOF samples after the sensing experiment.

Cobalt-based metal–organic framework for desulfurization of thiophene as a model fuel

“…Prominent bands at 764 and 677 cm −1 can be attributed the Co–O stretching frequency observed after adsorption without any further shift. 39,40 A new band at 2880 cm −1 indicates the S–H bond in the thiophene moiety. 41 The presence of the S–H stretching band at 2880 cm −1 in BITSH-1 after adsorption of thiophene strongly confirms the presence of adsorbed thiophene along with stretching frequency bands corresponding to CO, O–H and Co–O bands of the MOF network attributed to the interaction with thiophene.…”

Zr-NDI MOF Based Optical and Electrochemical Dual Sensor for Selective Detection of Dopamine

“…DPV experiments showed a substantial increment in current for DA oxidation, and the highest peak current was observed at 0.23 V (Figure 7a). The limit of detection (LOD) of dopamine was determined from the formula 3s/m, 36 where s is the standard deviation calculated from the blank electrolyte DPV readings and m is the slope obtained by plotting the linear fitting of anodic currents in the presence of dopamine against the concentration of dopamine added (Figure 7b). The standard deviation value was found to be 0.05619 from the blank electrolyte readings.…”

“…The presence of PET was confirmed by checking the HOMO (Highest occupied molecular orbital) and LUMO (Lowest unoccupied molecular orbital) values of MOF and dopamine. The LUMO and HOMO values of MOF and DA were calculated by determining the onset reduction ( E red ) and oxidation potential ( E oxi ) values from cyclic voltammetry study (Figure S16) and substituting them in the equations, E LUMO = −( E red + 4.741) and E HOMO = −( E oxi + 4.741) eV . The LUMO values for the MOF and dopamine are −3.9 eV and −3.4 eV, respectively, and the HOMO values are −5.2 eV and −5.0 eV, respectively (Figure ).…”

“…The LUMO and HOMO values of MOF and DA were calculated by determining the onset reduction (E red ) and oxidation potential (E oxi ) values from cyclic voltammetry study (Figure S16) and substituting them in the equations, E LUMO = −(E red + 4.741) and E HOMO = −(E oxi + 4.741) eV. 36 The LUMO values for the MOF and dopamine are −3.9 eV and −3.4 eV, respectively, and the HOMO values are −5.2 eV and −5.0 eV, respectively (Figure 4). As can be seen from the band gap diagram, the electron-rich dopamine HOMO level is higher than the MOF HOMO energy level.…”

A smart portable electrochemical sensor based on electrodeposited ferrocene-functionalized multiwalled carbon nanotubes for in vitro and in vivo detection of nicotine in tobacco samples

“…The current qualitative or quantitative detection methods for NIC and EVG include spectrophotometry, 12 fluorescence, 13 high-performance liquid chromatography, 14 surface-enhanced Raman spectroscopy, 15 electrochemiluminescence 16 and capillary electrophoresis. 17 However, these methods have the drawbacks of complex sample pretreatment steps, time-consuming procedures, high costs and the large size of the instruments, which seriously hinder large-scale analyses in practical production applications.…”