<p>Triazoles are crucial group of compounds that serve as versatile scaffolds for the synthesis of many pharmaceutical products. This study aimed to investigate the thermal, spectral and physical properties of a novel bisimine (4,6-triazolyl,2-phenylamino,1,3,5-triazine) (BITPAT). A novel triazine-based BITPAT organic chemosensor with a detection limit of 0.04&#xa0;μM was developed for sensing Cu(II) ions. The sensor response was analyzed using UV–Vis spectroscopy, which demonstrated exceptional selectivity and stoichiometry. A significant color shift from green to brown was observed for Cu(II) ions, characterized by an absorption peak at 250&#xa0;nm, offering critical insights into the sensing mechanism. The structural integrity was verified through elemental analysis, FTIR, NMR, UV–Visible and mass spectroscopic analyses. The electrochemical study confirmed the ability of BITPAT to detect Cu²⁺, with an LOD of 0.06&#xa0;μM. The structure was determined using the B3LYP/6-1G(d) method, and the analysis suggested a 1:1 interaction with the Cu(II) ions. The antioxidant potential of BITPAT was assesed using a DPPH free radical-scavenging system, which demonstrated considerable effectiveness. Ultraviolet–visible spectroscopy was employed to examine the binding interactions with CT-DNA, indicating intercalation. MTT- based cytotoxic assay was used to measure cell viability and effective anti-lung cancer activity in HepG-2 cancer cells. Molecular docking studies have elucidated interactions between metal complexes and biomolecules. The antagonistic activity of the synthesized triazine and its metal complexes against microbial pathogens was investigated, revealing that the triazine-based metal(II) complexes demonstrated enhanced activity compared with that of the ligand. This highlights the robust design of the sensor and its potential applicability in diverse analytical settings.</p> Graphical Abstract <p></p>