Anticancer Drug Extraction from Plasma Samples Using Three-Dimensional Polyoxometalate-Based Supramolecular Frameworks as Sorbents.

Four self-assembled inorganic-organic hybrid materials, namely, H{Na(H 2 O) 3 [Gd(PDA)(H 2 O) 2 ] 3 [BW 12 O 40 ]}·4H 2 O ( 1 ), H{Na(H 2 O) 3 [Tb(PDA)(H 2 O) 2 ] 3 [BW 12 O 40 ]}·3H 2 O ( 2 ), H{Na(H 2 O) 3 [Er(PDA)(H 2 O) 3 ] 3 [BW 12 O 40 ]}·H 2 O ( 3 ) (PDA = 1,10-phenanthroline-2,9-dicarboxylate), and [Pr 3 (H 2 O) 13 (pydc-OH) 2 ][BW 12 O 40 ]·12H 2 O ( 4 ) (pydc-OH = 4-hydroxy-2,6-pyridinedicarboxylate), were hydrothermally synthesized and structurally characterized. Hybrids 1 - 3 are isostructural and contain a Keggin unit, which is linked to lanthanoids to produce distinct trinuclear lanthanoid building blocks. The fragments are connected by anion-π and hydrogen bonding interactions to create 3D networks. In hybrid 4, a trimeric Pr-organic species bearing a Keggin unit forms a 2D coordination polymer, and then hydrogen bonding interactions between 2D layers lead to the formation of a 3D structure. These polyoxometalate-based frameworks were used as sorbents for the dispersive microsolid-phase extraction (D-μSPE) of two anticancer drugs (doxorubicin and epirubicin) in human plasma samples. Analytes were quantified and separated using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The method's linearity was between 0.8-500 ng mL -1 and 1.0-500 ng mL -1 for the antineoplastic drugs 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, human plasma samples from patients treated with doxorubicin or epirubicin were analyzed by using the D-μSPE-HPLC-FLD method.