A Highly Selective and Strong Anti-Interference Host-Guest Complex as Fluorescent Probe for Detection of Amantadine by Indicator Displacement Assay

Abstract

Amantadine (AMA) and its derivatives are illicit veterinary drugs that are hard to detect at very low concentrations. Developing a fast, simple and highly sensitive method for the detection of AMA is highly in demand. Here, we designed an anthracyclic compound (ABAM) that binds to a cucurbit[7]uril (CB[7]) host with a high association constant of up to 8.7 × 108 M−1. The host-guest complex was then used as a fluorescent probe for the detection of AMA. Competition by AMA for occupying the cavity of CB[7] allows ABAM to release from the CB[7]-ABAM complex, causing significant fluorescence quenching of ABAM (indicator displacement assay, IDA). The linear range of the method is from 0.000188 to 0.375 μg/mL, and the detection limit can be as low as 6.5 × 10−5 μg/mL (0.35 nM). Most importantly, due to the high binding affinity between CB[7] and ABAM, this fluorescence host-guest system shows great anti-interference capacity. Thus, we are able to accurately determine the concentration of AMA in various samples, including pharmaceutical formulations.

Benzimidazole–Piperazine–Coumarin/Cucurbit[7]uril Supramolecular Photoinduced Electron Transfer Fluorochromes for Detection of Carnosol by Stimuli-Responsive Dye Displacement and pKa Tuning

“…Also, CB8-encapsulated acridine dye was applied for the fluorescent detection of the peptide drug octreotide in aqueous solution utilizing the competitive host-assisted p K a shift . However, more recently, although IDA-driven sensing of amantadine drug with an anthracyclic-based probe (ABAM) in the presence of CB7 resulted in quenching of the emission of the probe with a recorded LOD of 0.35 nM, the dibucaine drug sensed by quenched emission of berberine, palmatine, and coptisine dyes gave a LOD of 6.0, 12.0, and 25.0 nM, respectively, while emission of the TPPE/CB7 complex enhanced with the addition of methamphetamine drug as a result of aggregate-induced emission produced a LOD of only 0.43 μM . Furthermore, Alzheimer disease drug “memantine” was sensed in the blood serum through the IDA mechanism with [2.2]­paracyclophane-derivative-indicator dyes and CB8 as a macrocycle .…”

“…The employment of cucurbit­[ n ]­urils (CBs) to tweak fluorescence signals utilizing the IDA strategy is well-known for detection of spectroscopically (optically) silent drug molecules. − The reported sensing strategies in these examples were conceivably dependent on numerous processes, such as the host-assisted interactions between aromatic rings, − the host-assisted aggregation-induced emission (AIE), or the dye deaggregation upon complexation . The utilization of other beneficial chemical equilibria and photochemical processes, which lead to the generation of fluorescent sensors that are highly sensitive to the analyte, has yet to be reported.…”

Covalent cucurbit[7]uril–dye conjugates for sensing in aqueous saline media and biofluids

“…62,63 Thus, amantadine concentration of $40 mM will be found for up to 24 h in urine. Following established routines for spectroscopic urine diagnostics, 19,20,64 urine samples were diluted with water in a 1 : 4 ratio in order to reduce the absorbance of real urine and to avoid inner lter effects. As the analyte concentration in urine samples is usually unknown, we devised a new method for using chemosensor 1 for quantifying amantadine in real urine samples.…”

“…Therefore, many reported CBn-based chemosensors are operational for sensing applications in deionized water or "minimal buffers" but were oen not suitable for applications in saline media or biouids, especially if their salt concentration is varying from sample to sample (matrix effects). 19,20 We recently demonstrated that the use of a high-affinity dye for CB8 enabled the detection of the drug memantine in blood serum by IDA. 21 However, this approach can have severe fundamental limitations, e.g.…”

Simple and fast detection of homocysteine by cucurbit[7]uril fluorescent probe based on competitive strategy

“…However, radioenzyme immunoassay utilizes radioactive adenosine, which can cause pollution and require expensive antibody costs. The instrumental analysis has some inevitable limitations such as tedious sample pretreatment, complicated chemical modification, precise instruments, long analysis time and low sensitivity [25]. Compared with the above analytical methods, the fluorescence probe method has attracted extensive concern owing to its rapidness, simplicity, high sensitivity, good stability, and low cost.…”