Carbon Dots Fluorescence-Based Colorimetric Sensor for Sensitive Detection of Aluminum Ions with a Smartphone

Abstract

In this work, blue emission carbon dots (CDs) are synthesized in the one-pot solvothermal method using naringin as precursor. The CDs are used to develop a ratiometric fluorescence sensor for the sensitive analysis of Al3+ with a detection limit of 113.8 nM. A fluorescence emission peak at 500 nm gradually appears, whereas the original fluorescence peak at 420 nm gradually decreases upon the increase in the Al3+ concentration. More importantly, the obvious color change of the CDs probe from blue to green under a 360 nm UV lamp can be identified by a smartphone and combined with the RGB (red/green/blue) analysis. This results in a visual and sensitive analysis of Al3+ with a detection limit of 5.55 μM. Moreover, the high recovery is in the 92.46–104.10% range, which demonstrates the high accuracy of this method for actual samples’ analysis. The use of a smartphone and the RGB analysis greatly simplifies the operation process, saves equipment cost, shortens the detection time, and provides a novel method for the instant, on-site, visual detection of Al3+ in actual samples.

Highly Fluorescent Carbon Dots as a Potential Fluorescence Probe for Selective Sensing of Ferric Ions in Aqueous Solution

“…Figure S2a shows the XRD pattern of assynthesized O-CDs. The pattern indicates the presence of two relevant peaks around at (2θ =) 23 and 43°, representing the (002) and (100) planes, respectively-authenticating the presence of carbon [42,43]. This observation well coincides with the HRTEM observation for the formation of crystalline carbon at the core of O-CDs.…”

A cucurbit[6]uril-carbon dot system: a potentially new bioimaging agent

“…Because of its simple operation, rapid analysis, high selectivity and high sensitivity, it has attracted people's attention. 7…”

“…Results showed that the framework of the Q[n]s remained intact during this process, and the obtained Q[n]-CQDs (n = 7, 8) were shown to be potential multicolor biomarkers according to cytotoxicity tests and cell imaging results. 30 In this paper, based on the previous large particle sizes of Q [7] and Q [8], this study has used a single Q [6] with a smaller particle size as the precursor, and phenylenediamine (o-phenylenediamine, m-phenylenediamine, p-phenylenediamine) as the doping reagent. Through a onestep hydrothermal synthesis, N and O groups with hydrophilic and recognition functions on the surface of CQDs were directly obtained.…”

“…Carbon quantum dots (m-Q[6]-CQDs) formed from Q [6] and m-phenylenediamine were studied. Compared with Q [7]-CQDs and Q [8]-CQDs, m-Q[6]-CQDs showed better light stability and salt tolerance. Meanwhile, m-Q [6]-CQDs can specifically recognize Hg 2+ and Al 3+ and allow for optical bioimaging to be performed on human prostate cancer (PC-3) cells; excellent selectivity and sensitivity to Hg 2+ and Al 3+ and impressive cell imaging ability are revealed.…”

Compact System for Colorimetric Sensor Arrays Characterization Based on Computer Screen Photo-Assisted Technology

“…Colorimetric sensors are devices whose fluorescence emission or absorption properties in the visible spectrum change upon interaction with specific targets. They are based on the variation of optical properties such as absorption and emission [20][21][22]. The operating principle of these sensors is relatively simple: they are used in combination with a light source, with a set wavelength and a detector.…”