Fatty-chain-switched cationic fluorescent probe for SCN−, PF6−, and HSO3− recognition in water: Study of anion selectivity and sensitivity

A New Cationic Fluorescent Probe for HSO3− Based on Bisulfite Induced Aggregation Self-Assembly

“…Based on this data, we can conclude that the CACs of these probes decreased on increasing the length of the fatty chain, in other words, the length of the fatty chain played an important role in the process of hydrophobic self-assembly in aqueous conditions. The longer the alkyl chain, the more hydrophobic the probe will be, and so a larger particle size will form [17]. This proposal was also corroborated by the dynamic light scattering (DLS) experiments: the particle size of TBPD 2+ -10 C, TBPD 2+ -11 C and TBPD 2+ -12 C was recorded at 51 nm, 53 nm and 75 nm, respectively (Figure S13).…”

“…To better understand the recognition mechanism of the series sensors, some essential experiments were performed. Firstly, we utilized methanol as the recognition medium to explore whether the polarity of solvents or H 2 O was favorable for the desolvation of the charge diffusion of HSO 3 − , and the results (Figure S20) suggested that no obvious changes had been observed after various anions were added into the mixture, which indicated that H 2 O may benefit the process of charge-diffuse anion recognition; by the means of the hydrophobic effect of these series of cationic sensors in water-containing condition, the different binding strength between the negatively charged HSO 3 − and positively charged sensors enable the identified anions HSO 3 − to suitably trigger the process of the sensor aggregation by the combinative effect of electrostatic ionic bonding, π-stacking of the π-conjugated aromatic moieties, and Van der Waals forces between the intermolecular alkyl chains [17,[20][21][22].…”

Pyrene-Based Cationic Fluorophores with High Affinity for BF4–, PF6–, and ClO4– Anions: Detection and Removal

“…Clearly, all the red emitters show a high affinity toward the anions BF 4 – , PF 6 – , and ClO 4 – . We infer that the dominant driving force is the electrostatic interactions between the target anions and the positively charged probes, − which induce the formation of anion−π + interactions, resulting in enhanced emission via molecular aggregates . The dynamic light scattering experiment shows that after DPPD-R interacts with the target anion, its average particle size increases (Table and Figures S12–S14).…”

“…Flood and co-workers reported a macrocycle that can specifically binding with BF 4 – , PF 6 – , and ClO 4 – in a MeOH/CH 2 Cl 2 system with a large binding constant, due to the synergetic effect of electrostatic interactions and a number of hydrogen-bonding interactions between the host–guest molecules. Kumar and Singh et al used a biphenyl linked bisbenzimidazolium fluorescent probe to achieve the highly selective recognition of ClO 4 – . , Moreover, our group has also developed a series of cationic water-soluble AIE fluorescent probes for anion detection via electrostatic interactions and weak interactions, such as Van der Waals forces and π–π interactions. − On the other hand, due to the presence of strong electrostatic interactions, the probe also can rapidly capture various anions which readily affiliate to form neutral clusters, thereby resulting in insoluble species, which can be removed by facile processes, and this could open up a potential pathway for the exploitation of ionic fluorescent probes as a tool for bringing the ionic contaminants (such as metal ions and anions) under control.…”

A novel bifunctional chemosensor for bioimaging in living cells with highly sensitive colorimetric and fluorescence detection of CN− and Al3+

“…Cations and anions widely exist in nature and play an important role in the biological, chemical and environmental fields. [1][2][3][4][5][6][7][8] The recognition of these ions has become the focus of research in recent years. 9,10 Cyanide is highly toxic to organisms because it can inhibit cellular respiration and adversely affects vascular, visual, central nervous, endocrine and metabolic functions.…”