Synthesis-Modification Integration: One-Step Fabrication of Boronic Acid Functionalized Carbon Dots for Fluorescent Blood Sugar Sensing

Abstract

In this paper, we have presented a novel strategy to fabricate fluorescent boronic acid modified carbon dots (C-dots) for nonenzymatic blood glucose sensing applications. The functionalized C-dots are obtained by one-step hydrothermal carbonization, using phenylboronic acid as the sole precursor. Compared with conventional two-step fabrication of nanoparticle-based sensors, the present "synthesis-modification integration" strategy is simpler and more efficient. The added glucose selectively leads to the assembly and fluorescence quenching of the C-dots. Such fluorescence responses can be used for well quantifying glucose in the range of 9-900 μM, which is 10-250 times more sensitive than that of previous boronic acid based fluorescent nanosensing systems. Due to "inert" surface, the C-dots can well resist the interferences from various biomolecules and exhibit excellent selectivity. The proposed sensing system has been successfully used for the assay of glucose in human serum. Due to simplicity and effectivity, it exhibits great promise as a practical platform for blood glucose sensing.

Characterization and Analytical Separation of Fluorescent Carbon Nanodots

“…In the case of IR analysis of C-dots samples, apart from the evaluation of hydroxyl (-OH) and carbonyl (C=O) functional groups on the C-dots surface [41,49,69,127], IR is also able to examine the doping of heteroatoms into the C-dots framework. Important examples include the identification of the presence of amide/amine (-CN/NH 2 ) [15,20,21,[37][38][39][40][41][42][43][44][45][46], alkyl sulfide (C-S) [33,[46][47][48][49], organosiloxane (Si-OSi/Si-O-C) [89,127,140,141], phosphates (P=O and P-O-R) [38,49,93], and boronic acid (B-O and B-N) [114,142,143] moieties attached on the surface of C-dots, providing evidence for introduction of nitrogen (N), sulfur (S), silicon (Si), phosphorus (P), and boron (B) heteroatoms into Cdots. The merits of this technique for the characterization of surface functionalization of C-dots are being low cost, simple, rapid, and easy for sample preparation.…”

“…For the characterization of Cdots, XPS has generally been used for the assessment of the elemental composition and the chemical bonds of C-dots in combination with IR. Doping of C-dots with nonmetallic heteroatoms such as N [43,49,56,99,114,121,122,134], S [14,24,46,49,87], Si [50,127,140,141], P [39,49,93], and B [114,142] has been characterized by XPS. A typical example of XPS analysis employed to estimate the surface states and chemical composition of nitrogen and sulfur-codoped C-dots (SNCNs) was displayed in Figure 6 [46].…”

Photoluminescent Detection of Nitrite with Carbon Nanodots Prepared by Microwave-assisted Synthesis

“…With the formation of aggregated CNDs, the PL of the CNDs is quenched, which is considered as the surface quenching states-induced mechanism. 27 Figure 6 shows the dependence of the PL intensity on the concentrations of nitrite and nitrate. With an increase in nitrite concentration, the PL intensity of the CNDs decreased after the reaction with diazotized p-PDA at pH 10.2.…”

Highly sensitive on-site detection of glucose in human urine with naked eye based on enzymatic-like reaction mediated etching of gold nanorods

“…2D). The detection limit was calculated to be 0.1 μM (3σ rule), which is two orders of magnitude lower than other GNRs-based glucose sensors (Liu et al, 2013;Saa et al, 2014) and is almost the lowest among nanoparticle-based glucose sensors (Table S1, Supplementary Information) (Bi et al, 2015;Bo et al, 2013;Jiang et al, 2010;Kong et al, 2014;Luo et al, 2015;Radhakumary and Sreenivasan, 2011;Shen and Xia, 2014;Shiang et al, 2009;Su et al, 2012Su et al, , 2015bXia et al, 2013;Yi et al, 2013;Zayats et al, 2005;Zhao et al, 2015;Zheng et al, 2015). In addition, the small error bar of the data indicates the method has very high stability (Fig.…”