A novel fluorescent probe based on rhodamine hydrazone derivatives bearing a thiophene group for Al³⁺

Abstract

In the present work, a novel 5-methyl-thiophene-carbaldehyde-functionalized rhodamine 6G Schiff base (RA) was designed and easily prepared as an Al(3+) fluorescent and colorimetric probe, which could selectively and sensitively detect Al(3+) by showing enhanced fluorescence emission. Meanwhile distinct color variation from colorless to pink also provided 'naked eye' detection of Al(3+), due to the ring spirolactam opening of the rhodamine derivative. Other metal ions (including K(+), Mg(2+), Na(+), Ba(2+), Mn(2+), Cd(2+), Fe(2+), Ni(2+), Pb(2+), Zn(2+), Hg(2+), Co(2+), Li(+), Sr(2+) and Cu(2+)) could only induce limited interference. The detection limit of the fluorescent probe was estimated to be 4.17 × 10(-6) M, the binding constant of the RA-Al(3+) complex was 1.4 × 10(6) M(-1). Moreover, this fluorescent probe RA possessed high reversibility. As aluminum is a ubiquitous metal in nature and plays vital roles in many biological processes, this chemosensor could be explored for biological study applications.

Dual-binding pyridine and rhodamine B conjugate derivatives as fluorescent chemosensors for ferric ions in aqueous media and living cells

“…In view of these facts, many new rhodamine derivatives as the fluorescent probes towards metal ions are getting more and more popular among researchers. [40][41][42][43][44][45][46][47] Meanwhile, rhodaminebased enhanced probes for Fe 3+ have been designed and discussed in recent years. [48][49][50][51][52] Most of these probes have difficult problems to solve, such as the need for expensive raw materials, complex synthesis steps, poor water solubility, poor biocompatibility, etc.…”

A Benzothiazole-Based Fluorescent Probe for Ratiometric Detection of Al3+ in Aqueous Medium and Living Cells

“…Most of them for Al 3+ are required to be performed in pure organic solvents or organic–water mixed solvents. Owing to the strong hydration of Al 3+ in aqueous solution, these probes suffer from the great limitation in imaging applications. , In addition, many fluorescent sensors underwent small Stokes shifts and thus encounter some interference influence in fluorescence analysis, including self-absorption or inner filter effects. , …”

“…Owing to the strong hydration of Al 3+ in aqueous solution, these probes suffer from the great limitation in imaging applications. 32,33 In addition, many fluorescent sensors underwent small Stokes shifts and thus encounter some interference influence in fluorescence analysis, including self-absorption or inner filter effects. 34,35 Contrary to the aggregation-caused quenching (ACQ) effect, a number of fluorescent sensors that exhibit AIE (aggregationinduced emission) or AIEE (aggregation-induced enhanced emission) phenomenon possess better attributes and have received more and more attention due to the highly emissive aggregated state.…”

Fabrication of an acylhydrazone based fluorescence probe for Al3+

“…Recently, the fluorescent method has become popular due to its operational simplicity, high selectivity and sensitivity, real-time response and naked eye detection. Most of the sensors are rhodamine derivatives [40][41][42][43][44][45], naphthol derivatives [46][47][48], quinoline derivative [49]. Some are based on julolidine and tryptophan moieties [50], conjugated copolymer-ATP supramolecular complex [51], Organic Framework [52]，gold nanoparticles [53,54].…”