Jian Qu1, Xin Zhang2, Yifan Liu1, Yichao Xie1, Jiawei Cai1, Guojin Zha3, Su Jing4. 1. School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng, 224051, People's Republic of China. 2. School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng, 224051, People's Republic of China. xinzhang@ycit.edu.cn. 3. School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, People's Republic of China. 4. School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, People's Republic of China. sjing@njtech.edu.cn.
Abstract
Novel colorimetric and ratiometric fluorometric dual-mode N, P-co-doped carbon nanodots, BPEI-CDs, for highly sensitive and selective detection of formaldehyde (FA) were successfully prepared from N-(phosphonomethyl)iminodiacetic acid (PMIDA) and branched polyethyleneimine (BPEI). The treatment of FA caused a remarkable linear enhancement of ratiometric fluorescence (F501 nm/F408 nm) in a wide range of 0-40 μM with a detection limit (LOD) of 0.47 μM (3σ/k), along with distinct color changes from colorless to light yellow. Mechanistic study shows that this electron-rich system, formed by the cooperative roles of N and P, promoted the FA-induced Schiff bases formation reaction, which contributed to the CD aggregation-induced emission (AIE) "turn-on" response and enhancement of π-conjugation-induced bathochromic behaviors. Furthermore, N, P-co-doped BPEI-CDs were successfully applied to the determination of FA in bean sprout samples. Using the standard addition method, the recoveries ranged from 96.9 to 101.8%, and the relative standard deviation (RSD) was in the range 2.23 to 3.21%. The application for intracellular FA sensing further verified that this novel nanoprobe may offer a new venue for the design of simple, low-cost, and sensitive biosensors. Graphical abstract.
Novel colorimetric and ratiometric fluorometric dual-mode n class="Chemical">N, P-co-dopedpan> class="Chemical">carbon nanodots, BPEI-CDs, for highly sensitive and selective detection of formaldehyde (FA) were successfully prepared from N-(phosphonomethyl)iminodiacetic acid (PMIDA) and branched polyethyleneimine (BPEI). The treatment of FA caused a remarkable linear enhancement of ratiometric fluorescence (F501 nm/F408 nm) in a wide range of 0-40 μM with a detection limit (LOD) of 0.47 μM (3σ/k), along with distinct color changes from colorless to light yellow. Mechanistic study shows that this electron-rich system, formed by the cooperative roles of N and P, promoted the FA-induced Schiff bases formation reaction, which contributed to the CD aggregation-induced emission (AIE) "turn-on" response and enhancement of π-conjugation-induced bathochromic behaviors. Furthermore, N, P-co-dopedBPEI-CDs were successfully applied to the determination of FA in bean sprout samples. Using the standard addition method, the recoveries ranged from 96.9 to 101.8%, and the relative standard deviation (RSD) was in the range 2.23 to 3.21%. The application for intracellular FA sensing further verified that this novel nanoprobe may offer a new venue for the design of simple, low-cost, and sensitive biosensors. Graphical abstract.