Response of Ancillary Azide Ligand in Designing a 1D Copper(II) Polymeric Complex along with the Introduction of High DNA- and HAS-Binding Efficacy, Leading to Impressive Anticancer Activity: A Compact Experimental and Theoretical Approach

Manik Das; Somali Mukherjee; Md Maidul Islam; Indranil Choudhuri; Nandan Bhattacharyya; Bidhan Chandra Samanta; Basudeb Dutta; Tithi Maity

doi:10.1021/acsomega.2c01403

Response of Ancillary Azide Ligand in Designing a 1D Copper(II) Polymeric Complex along with the Introduction of High DNA- and HAS-Binding Efficacy, Leading to Impressive Anticancer Activity: A Compact Experimental and Theoretical Approach

ACS Omega. 2022 Jun 28;7(27):23276-23288. doi: 10.1021/acsomega.2c01403. eCollection 2022 Jul 12.

Authors

Manik Das¹, Somali Mukherjee², Md Maidul Islam³, Indranil Choudhuri⁴, Nandan Bhattacharyya⁴, Bidhan Chandra Samanta⁵, Basudeb Dutta⁶, Tithi Maity¹

Affiliations

¹ Department of Chemistry, Prabhat Kumar College, Contai, Purba Medinipur, Contai 721404, India.
² School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, West Bengal, India.
³ Department of Chemistry, Aliah University, Kolkata 700064, India.
⁴ Department of Chemistry, Panskura Banamali College, Panskura 721152, India.
⁵ Department of Chemistry, Mugberia Gangadhar Mahavidyalaya, Purba Medinipur 721425, India.
⁶ Department of Chemical Science, IISER Kolkata, Mohanpur, Kolkata 741246, India.

Abstract

A new versatile azide-bridged polymeric Cu(II) complex, namely, [Cu(L)(μ_1,3-N₃)]_∞ (1), was synthesized utilizing an N,N,O-donor piperidine-based Schiff base ligand (E)-4-bromo-2-((2-(-1-yl)imino)methyl)phenol (HL), obtained via the condensation reaction of 1-(2-aminoethyl) piperidine and 5-bromo salicylaldehyde. The single-crystal X-ray diffraction analysis reveals that complex 1 consists of an end-to-end azido-bridged polymeric network, which is further rationalized with the help of a density functional theory (DFT) study. After routine characterization with a range of physicochemical studies, complex 1 is exploited to evaluate its biomedical potential. Initially, theoretical inspection with the help of a molecular docking study indicated the ability of complex 1 to effectively bind with macromolecules such as DNA and the human serum albumin (HSA) protein. The theoretical aspect was further verified by adopting several spectroscopic techniques. The electronic absorption spectroscopic analysis indicates a remarkable binding efficiency of Complex 1 with both DNA and HSA. The notable fluorescence intensity reduction of the ethidium bromide (EtBr)-DNA adduct, 4',6-diamidino-2-phenylindole (DAPI)-DNA adduct, and HSA after the gradual addition of complex 1 authenticates its promising binding potential with the macromolecules. The retention of the canonical B form of DNA and α form of HSA during the association of complex 1 was confirmed by implementing a circular dichroism spectral study. The association ability of complex 1 with macromolecules further inspired us to inspect its impact on different cell lines such as HeLa (cervical cancer cell), PA1 (ovarian cancer cell), and HEK (normal cell). The dose-dependent and time-dependent in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay suggests an effective antiproliferative property of complex 1 with low toxicity toward the normal cell line. Finally, the anticancer activity of complex 1 toward carcinoma cell lines was analyzed by nuclear and cellular staining techniques, unveiling the cell death mechanism.