In this paper, we report the hydrothermal synthesis and characterization of four organic–inorganic hybrid assemblies: H0.88{Na (H2O)3[Gd(PDA)(H2O)2]3[BW12O40]0.88[SiW12O40]0.12}·2H2O (1) H0.79{Na(H2O)3[Tb(PDA)(H2O)2]3[BW12O40]0.79[SiW12O40]0.21}·3H2O (2) H{Na(H2O)3[Er(PDA)(H2O)3]3[BW12O40]}·4H2O (3) (H2PDA =1,10-phenanthroline-2,9-dicarboxylic acid) and [Pr3(H2O)12(pydc-OH)2][BW12O40]·12H2O (4) (H2pydc-OH = chelidamic acid; 4-hydroxy-2,6-pyridinedicarboxylic acid). The structure of synthesized materials characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. Structural characterizations by single-crystal X-ray diffraction show that 1-3 are isostructural and each one contains a Keggin-type polyoxometalate (POM) connected by three lanthanoids to construct discrete trinuclear lanthanoid building blocks. These discrete molecules connect to each other through hydrogen-bonding and anion–π interactions to yield 3D supramolecular networks. Hybrid 4 presents a 2D coordination polymer constructed by trimeric Pr-organic species and the Keggin [BW12O40] 5‒ POM which extends to a 3D supramolecular framework via hydrogen-bonding interactions between the 2D layers. Interestingly, the 3D supramolecular frameworks exhibit adsorption ability of basic drugs. So, these frameworks were used as sorbents in dispersive micro-solid-phase extraction (D-μSPE) for the extraction of two anticancer drugs (doxorubicin, and epirubicin) in human plasma samples. High-performance liquid chromatography (HPLC) was used for analyte separation and determination. The linearity of the method was in the range of 0.8‒500 ng mL−1 and 1.0‒500 ng mL−1 for doxorubicin and epirubicin, respectively. The limits of detection (S/N = 3) were in the range of 0.2−0.3 ng mL−1 while the precision was in the range of 3.5−4.3%. Finally, the method was applied to extract and analyze human plasma samples from patients treated with doxorubicin, or epirubicin.

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