Spermidine has emerged as a promising biomarker for the early-stage diagnosis of cancer in humans. A novel extractive spectrophotometric analytical method has been developed for the determination of spermidine in urine samples. This technique leverages the selective extraction of spermidine from complex matrices using a cucurbit[7]uril-truxene derivative (Q[7]-Cs-Tr) as a fluorescent extractant. The Q[7]-Cs-Tr forms a stable host-guest complex with spermidine, facilitating its extraction from the aqueous phase to the organic phase. The formation of this complex results in a decrease in the fluorescence intensity of the Q[7]-Cs-Tr in the organic phase. Key factors influencing extraction efficiency, including the type of dispersed organic solvent, extractant concentration, solution pH, extraction times, and equilibrium time, were thoroughly investigated. The method demonstrated minimal interference from various metal ions, anions, amino acids, and other biogenic amines. It also exhibited a low limit of detection (8.6 nM), excellent linearity (R 2 = 0.9972), and high repeatability (RSD = 2.4 % intra-day, RSD = 3.6 % inter-day). The proposed method was successfully applied to determine spermidine levels in urine samples, yielding satisfactory recoveries ranging from 96.3 % to 103.5 %. Compared to existing methods, this approach is simple, reliable, highly sensitive, and exhibits low interference, making it a potential robust tool for clinical diagnostics.
Pretreatment technology suffers from drawbacks such as tedious operation, low efficiency, and poor selectivity. Hence, we presented a singly capped cucurbit[7]uril-mediated magnetic solid phase extraction (Q[7]-MagSPE) combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for multiresidue analysis of 20 pesticides. The Q[7]-MagSPE was constructed by assembling Q[7] onto the gold magnetic nanoparticles (GoldMag) via the reaction between one of the electron-rich carbonyl portals of Q[7] and gold. The host-guest interaction activity of supramolecules, the high dispersibility and easy separability of GoldMag were integrated in the Q[7]-MagSPE. The detection limits for 20 pesticides were lower than 10.3 ng/kg, and the recoveries were 71.55 – 110. 6 % . Moreover, the reusability of the Q[7]-GoldMag and effect of washing times on the pesticide residue were evaluated to be satisfactory. Therefore, the Q[7]-MagSPE provides a rapid and robust pretreatment method for the multiresidue determination of pesticides in vegetables, which is of great significance for food safety.
Trace amounts of pharmaceuticals and personal care products (PPCPs) in aquatic environment poses a non-negligible risk to human health. Here, an environmentally friendly cucurbit[7]uril-mediated magnetic-assisted matrix solid phase dispersion (Q[7]- m -MSPD) extraction method was developed for extracting PPCPs from complex aquatic organisms. The extraction of PPCPs were achieved via the host-guest interaction between Q[7] and targets, significantly reducing the matrix interference. Gold magnetic nanoparticles (AuMNPs) were chelated to Q[7]-target complexes and used for purification and enrichment via magnetic solid-phase extraction (MSPE), effectively replacing the complex operation of sample loading and elution on SPE columns in MSPD. Coupled with high performance liquid chromatography-tandem mass spectrometry, multiple analysis of 14 PPCPs in 3 aquatic plants and an aquatic animal were achieved, with detection limits ranging from 0.0015 to 0.0179 μg/kg, recoveries ranging from 71.06 to 113.6 %, and enrichment factors within 46 to 152. The green chemistry assessment confirmed the environmental friendliness, economic feasibility, and application potential of the Q[7]- m -MSPD, with an AGREE score of 0.63 and a BAGI score of 72.5. By integrating the merits of MSPD and MSPE, the proposed approach exhibited high sensitivity and anti-interference capability, simple operation, and great environmental friendliness. Therefore, the approach provided a green method for simultaneously detecting multiple hazardous residues in complex matrices owing to the broad-spectrum molecular recognition capability of Q[7] , which has a good application prospect in food safety and environmental monitoring.
危险品化学品经营许可证（带存储）