Highly sensitive and selective detection of dopamine with boron and sulfur co-doped graphene quantum dots

Abstract

In this work, we report, the synthesis of Boron and Sulfur co-doped graphene quantum dots (BS-GQDs) and its applicability as a label-free fluorescence sensing probe for the highly sensitive and selective detection of dopamine (DA). Upon addition of DA, the fluorescence intensity of BS-GQDs were effectively quenched over a wide concentration range of DA (0–340 μM) with an ultra-low detection limit of 3.6 μM. The quenching mechanism involved photoinduced electron transfer process from BS-GQDs to dopamine-quinone, produced by the oxidization of DA under alkaline conditions. The proposed sensing mechanism was probed using a detailed study of UV–Vis absorbance, steady state and time resolved fluorescence spectroscopy. The high selectivity of the fluorescent sensor towards DA is established. Our study opens up the possibility of designing a low-cost biosensor which will be suitable for detecting DA in real samples.

A bacterial cellulose-based LiSrVO4:Eu3+ nanosensor platform for smartphone sensing of levodopa and dopamine: point-of-care diagnosis of Parkinson's disease

“…The quenching phenomenon requires that the energy level of the electron-accepting group is lower than the lowest unoccupied molecular orbital (LUMO) energy of the fluorescent material, or that non-covalent interactions occur between the fluorescent material and analyte molecules. 98–100 As shown in Fig. 6, upon excitation of the LSV:0.015Eu 3+ nanoplates, electrons were promoted into the conduction band from their valence band, resulting in the formation of a positively charged hole in the valence band and a free electron in the conduction band.…”

Advances in Novel Nanomaterial-Based Optical Fiber Biosensors—A Review

“…Zero-dimensional nanomaterials mostly exist in spherical or quasi-spherical shapes with diameters less than 100 nm [ 47 , 64 ]. The most common 0D materials used in sensing applications are carbon QDs (CQDs) [ 65 , 66 ], semiconductor quantum dots (SQDs) [ 67 , 68 ], graphene quantum dots (GQDs) [ 62 , 69 , 70 , 71 ], CdTe QDs [ 72 , 73 , 74 ], and precious metal NPs such as silver nanoparticles (AgNPs) and AuNPs [ 18 , 20 , 75 , 76 , 77 , 78 ]. However, 0D nanomaterial-based sensing is still in its infancy, and the practical applicability of these nanosensors still has room for advancement, which needs to be solved shortly.…”

“…Two-dimensional metal films and three-dimensional (3D) nanoarrays play an important role in enhancing the local electric field of optical fiber structures so they can be used in the development of SPR-based optical fiber biosensors. These sensing systems can detect a large number of molecules of clinical relevance, including glucose [ 56 , 57 ], bacteria [ 58 , 59 ], cancer cells [ 6 , 60 ], dopamine [ 61 , 62 , 63 ], deoxyribonucleic acid (DNA) [ 41 ], and so on. The applications of different types of nanomaterials based on different sensing principles are represented in Figure 1 .…”

Electrochemical detection of cholesterol in human biofluid using microneedle sensor

“…30 Despite the significant progress in electrochemical biosensors, these approaches rely on the use of nanomaterial-based electrode surface modification processes and remain unable to continuously monitor the cholesterol level in physiologically relevant fluids. [31][32][33][34][35][36][37] The development of a wearable electrochemical sensing platform that can address the abovementioned issues by continuously monitoring the cholesterol level in interstitial fluid with high specificity is highly desirable.…”