Reliable and sensitive procedure for quantification of antiseptic chlorhexidine di-gluconate via quenching the fluorescence of lanthanide-EDTA- probe

Novel sensing probe using Terbium-sensitized luminescence and 8-hydroxyquinoline for determination of prucalopride succinate: green assessment with Complex-GAPI and analytical Eco-Scale

“…From the literature, we found that the addition of a secondary ligand that could bind to the Tb +3 and displace the solvent molecules, which act as effective quenchers, will intensify the emitted light. EDTA was reported to be used with Tb +3 and effectively enhance the luminescence intensity [ 4 ]. Also, we found that 8HQ was used previously with La +3 for the determination of DNA with the same concept of secondary ligand but to our knowledge, it wasn’t used before with Tb +3 .…”

“…The lanthanide-sensitized luminescence method is widely used for the determination of organic ligands by forming a stable luminescent complex between the ligand and one of the lanthanide ions; especially terbium (Tb +3 ), erbium (Eu +3 ), and lanthanum (La +3 ) [ 2 ]. The luminescence of the formed complex arises from the effective intra-molecularly energy transfer between the overlapped excited triplet state of the ligand to the localized excited state of the lanthanides which is then emitted by a radiative transition; resulting in what is known as antenna phenomena (the energy absorbed by the ligand is emitted through the lanthanides) [ 3 , 4 ]. That is why the excitation wavelength of the formed complex is specific to the ligand while the emission wavelength is specific to the lanthanides [ 5 ].…”