Modified natural clinoptilolite with quercetin and quercetin dihydrate and the study of their anticancer activity

Natural zeolite of the clinoptilolite type (CT, particle size up to 200 μm) and its modified forms with different content (0.06–5%) of pharmaceutically active compounds (type of flavonoids): quercetin (Q) and quercetin dihydrate (QD) have been investigated by thermal analyses TG, DTA and DTG, FTIR spectroscopy, fluorescence spectroscopy, X-ray powder diffractometry, determination of the surface areas and the pore volumes by low-temperature adsorption of nitrogen and atomic force microscopy. The analyses checked the presence of Q or QD in modified zeolitic products (CTQ and CTQD).Natural zeolite of the clinoptilolite type and their modified forms CTQ and CTQD with low content (0.06% and 1%) of Q and QD have been used for the study of their anticancer activity. Carcinoma cell lines Jurkat, CEM, HeLa, MCF7, A549 and MDA were treated with various amounts of natural clinoptilolite and their modified forms CTQ and CTQD. The water content of the channel system influences the cytotoxicity of zeolite. The results of the study of pure CT thermally activated at two different temperatures 110 and 400 °C confirmed the better cytotoxicity of CT activated at 110 °C (CT110) with higher content of water in comparison with CT activated at 400 °C (CT400). Clinoptilolite modified with quercetin dihydrate (CTQD) has shown better cytotoxicity compared with clinoptilolite modified with quercetin (CTQ).

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Modified natural zeolite (CT) with quercetin or quercetin dihydrate were synthesised. ► Anticancer activity of CT and its modified forms CTQ and CTQD were studied. ► The water content of the channel system influences the cytotoxicity of zeolite. ► Modified CTQD has shown better cytotoxicity compared with modified CTQ.