Polymer-Based Terbium Complex as a Fluorescent Probe for Cancer Antigen 125 Detection: A Promising Tool for Early Diagnosis of Ovarian Cancer.

A novel photoprobe, Tb-acetylacetone (Tb-ACAC) doped within a modified epoxy cellulose polymer immobilized with CA-125 monoclonal antibody, offers an accurate and highly selective method for early ovarian cancer (OC) diagnosis by detecting cancer antigen 125 (CA-125) in serum samples. This approach leverages quenching of the Tb-ACAC luminescence upon binding to CA-125. Characterization of the photoprobe film through UV-vis and fluorescence measurements confirmed the presence of Tb-ACAC within the polymer matrix. In aqueous solution (pH 6.8, λ(ex) = 365 nm), the characteristic emission band of Tb-ACAC at λ(em) = 546.2 nm exhibited significant quenching upon CA-125 binding. This quenching effect enabled the sensitive and specific detection of CA-125 in diverse serum samples from OC patients, demonstrating the applicability, simplicity, and effectiveness of this novel approach.