Synthesis, spectral investigations, antimicrobial activity and DNA-binding studies of novel charge transfer complex of 1,10-phenanthroline as an electron donor with π-acceptor p-Nitrophenol

Proton or charge transfer (CT) complex of donor, 1,10-phenanthroline (Phen) with π-acceptor, p-Nitrophenol (PNP) has been studied spectrophotometrically in methanol at room temperature. The binding of the CT complex with calf thymus (ct) DNA has been investigated by fluorescence spectrum, to establish the ability of the CT complex of its interaction with DNA. Stern–Volmer quenching constant (Ksv) has also been calculated. The formation constant (KCT), molar extinction coefficient (εCT), free energy (ΔGo) and stoichiometric ratio of the CT complex have been determined by Benesi–Hildebrand equation. The stoichiometry was found to be 1:1. The CT complex was screened for its pharmacology as antibacterial and antifungal activity against various bacterial and fungal strains, showing excellent antibacterial and antifungal activity. The newly synthesized CT complex has been characterized by FTIR spectra, elemental analysis, 1H NMR, electronic absorption spectra. TGA–DTA studies were also carried out to check the stability of CT complex.