Abstract
Carbon dots (CD) have excellent stability and fluorescence activity, and have been widely used in fluorescence methods. However, there are no reports about using CD as catalysts to amplify SERS signals to detect trace sulfate. Thus, preparing CD catalysts and their application in SERS sulfate-sensing are significant. In this article, highly catalytic N-doped carbon dots (CDN) were prepared by a hydrothermal procedure. CDN exhibited strong catalysis of the gold nanoparticle (AuNP) reaction between HAuCl4 and H2O2. Vitoria blue 4R (VB4R) has a strong SERS peak at 1614 cm−1 in the formed AuNP sol substrate. When Ba2+ ions were added, they were adsorbed on a CDN surface to inhibit the CDN catalytic activity that caused the SERS peak decreasing. Upon addition of analyte SO42−, a reaction with Ba2+ produced stable BaSO4 precipitate and CDN, and its catalysis recovered to cause SERS intensity increasing linearly. Thus, an SERS method was developed for the detection of 0.02–1.7 μmol/L SO42−, with a detection limit of 0.007 μmol/L.
Highlights
Because carbon dots (CD) have excellent stability, excellent chemical properties, high fluorescence activity, anti-photobleaching abilities and low cell toxicity [1,2,3,4,5], they are of interest to scientists.Based on the redox, complex, enzyme and immune reactions, CD have been used to determine chlorine ion, phosphate, ATP, ferric ion, hydrogen peroxide, glucose, immunoglobulin G, biological thiols, deoxyribonucleic acid, trypsin and so on [6,7,8,9,10,11]
Highly catalytic N-doped carbon dots were prepared for the HAuCl4 -H2 O2 reaction, and a new and sensitive SERS quantitative analysis method was proposed for the determination of sulfate in water and beer samples, based on the CD catalysis
Preparation of N-doped carbon dot solution (CDN ): A 1 g of citric acid and 0, 0.5, 1.0 and 2.0 g urea were dissolved respectively in 30 mL water, and the brown yellow transparent solution was transferred to a polytetrafluoroethylene autoclave
Summary
Because carbon dots (CD) have excellent stability, excellent chemical properties, high fluorescence activity, anti-photobleaching abilities and low cell toxicity [1,2,3,4,5], they are of interest to scientists. Feng et al [15] reported a graphene quantum dots-aptamer fluorescent probe to detect lead (II) ions (as low as 0.6 nmol/L). There are no reports about preparation of highly catalytic N-doped carbon dots and their application to SERS quantitative analysis. For analysis of trace SO4 2− , there are visible–ultraviolet spectrophotometry, turbidimetry, fluorescence spectrophotometry, electrochemical analysis, radiochemical analysis, resonance Rayleigh scattering, ion chromatography, and so on [25,26,27,28,29,30] In this experiment, highly catalytic N-doped carbon dots were prepared for the HAuCl4 -H2 O2 reaction, and a new and sensitive SERS quantitative analysis method was proposed for the determination of sulfate in water and beer samples, based on the CD catalysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
