Selective Colorimetric Detection of Cancer Cells Based on Iron/Copper Nanocatalyst Peroxidase Activity

Abstract

Nanomaterial based enzyme i.e., nanozymes have the potential to overcome natural enzymes&#x2019; major shortcomings, hence the development of effective artificial enzymes is a burgeoning topic in nanobiotechnology. A novel nanostructured hybrid enzyme was constructed as a mimetic enzyme for <i>i</i> n <i>v</i> itro cancer cell detection and therapeutic treatment in the current study. The iron-copper (FeCu) nanocatalyst was prepared and immobilized with 2-DG, as cancer cell targeting ligand 2-DG can interact with the GLUT receptor overexpressed in several cancer cells. FeCu&#x0040;2-DG showed enhanced peroxidase-like activity and oxidized the substrate 3,<inline-formula> <tex-math notation="LaTeX">$3^\prime $ </tex-math></inline-formula>,5,<inline-formula> <tex-math notation="LaTeX">$5^\prime $ </tex-math></inline-formula>-tetramethylbenzidine (TMB) into blue color product in the presence of hydrogen peroxide (H₂O₂). Peroxidase activity of nanocatalyst can be well utilized as selective and quantitative colorimetric sensor for detection of liver cancer cells (HepG2). Sensor is shown to detect HepG2 cells in linear range of 50&#x2013;1000 cells/mL, with detection limit of 20 cells/mL. Additionally, nanocatalyst can also be used as H₂O₂ and ascorbic acid mediated therapeutic effect in cancer cells. Phloretin (GLUT inhibitor) treated cells showed the negligible interaction with particle in comparison of control non-treated cells. Thus, confirming the selective interaction of synthesized particle with GLUT overexpressed cancer cells. Based on the simple peroxidase function, the developed hybrid might be a promising candidate for clinical cancer diagnosis and therapy.