Ag nanoparticles immobilized on guanidine modified-KIT-5 mesoporous nanostructure: Evaluation of its catalytic activity for synthesis of propargylamines and investigation of its antioxidant and anti-lung cancer effects

The current study involves the novel synthesis of Ag nanoparticles (Ag NPs) decorated biguanidine modified mesoporous silica KIT-5 following post-functionalization approach (KIT-5-bigua-Ag). The tiny Ag NPs were being stabilized over the in situ prepared biguanidine ligand. The high surface area material was characterized using advanced analytical methods like Fourier Transformed infrared (FT-IR) spectroscopy, N-2-adsorption-desorption isotherm, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spec-troscopy (EDS), and X-ray Diffraction study (XRD). The material was having large pore cage like structure with pore diameter of 8-10 nm. TEM study displayed the particles size of deposited Ag NPs were 10-15 nm. The KIT-5-bigua-Ag nanocomposite had a significantly high surface area of 318 m(2)/g (BET analysis). Towards the chemical applications of the material, we headed the three component reaction of aldehydes, amines and alkynes (A(3) coupling) with good to excellent yields (70-98%) of diverse Propargylamines. The catalyst was easily isolable and reused in 8 cycles without any leaching and considerable change in its reactivity. In addition, the KIT-5-bigua-Ag nanocomposite was engaged in biological assays like study of anti-oxidant properties by DPPH mediated free radical scavenging test using BHT as a reference molecule. Thereafter, on having a significant IC50 value in radical scavenging assay, we extended the bio-application of the desired nanocomposite in anticancer study of A549 cell of human lung in-vitro conditions. In the cytotoxicity and anti-human lung studies, the nanocomposite was treated to lung cancer A549 cell line following MTT assay. The cell viability of malignant lung cell line reduced dose-dependently in the presence of KIT-5-biguanidine-Ag nanocomposite. IC50 values of the nanocomposite were observed to be 915.22 lg/mL against A549 cell line. So, these results suggest that KIT-5-biguaAg as a novel chemotherapeutic nanocomposite have a suitable anticancer activity against lung cell lines. (C) 2021 Published by Elsevier B.V. on behalf of King Saud University.