Functionalized gold nanorods turn-on chemosensor for selective detection of Cd2+ ions, bio-imaging, and antineoplastic evaluations
Marwa N. El‐Nahass, Eman A. Bakr, Tarek A. Fayed, Wafaa M. Hamada, Maha M. Salem, Aliaa M. Radwan
Abstract
Abstract A colorimetric turn-on chemosensor based on gold nanorods, Au NRs, has been developed to enable rapid, facile, and simultaneous detection of hazardous metal ions. This study involved the functionalization of gold nanorods with (9,10-dioxo-9,10-dihydro-anthracen-1-yl)-dithiocarbamic acid (DTAD) through the utilization of synthetic photo-irradiation and ultrasound techniques. Various spectroscopic methods were employed to characterize both the synthesized gold nanorods and the chemosensor. The optical response of this sensor was investigated with respect to a range of metal ions, including Mg 2+ , K + , Ca 2+ , Mn 2+ , Fe 3+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , and Pb 2+ . The results reveal that the DTAD-functionalized gold nanorods chemosensor effectively discriminates all the investigated metal ions, with Cd 2+ ions exhibiting higher sensitivity and selectivity compared to the other metal ions. Moreover, the anticancer impact of both gold nanorods and DTAD-functionalized gold nanorods was investigated on a panel of cell lines as breast cancer (MCF-7), liver cancer (HepG-2), and colon cancer (Caco-2) using MTT assay. Further, the morphological features and Annexin V using flow cytometry were carried. Comparative analysis with a free chemosensor showed that fluorescence images of living cells were notably brighter in the presence of Cd 2+ , highlighting the efficacy of DTAD-functionalized gold nanorods as a fluorescent biosensor for Cd 2+ ions. Additionally, the in vitro anticancer study showed that gold nanorods significantly inhibited the growth of all cancer cells than DTAD-functionalized gold nanorods with best antiproliferative effect on HepG-2 hepatocellular carcinoma with IC 50 values equal to 1.971 ± 1.28, 40.95 ± 2.56 µg/mL, respectively, compared to DOX. Also, the alteration in the HepG-2 morphological shape and Annexin V results confirmed the great antineoplastic effect of Au NRs than DTAD-Au NRs.