Sensitive Assessment of Ketotifen Levels in Tablets and Plasma Using a Photoinduced Electron Transfer (PET) Inhibition Spectrofluorimetric Approach

Ketotifen (KTF) is a type of asthma medication that is taken along with other antiasthma medications and may reduce the frequency, severity, and duration of asthma symptoms or attacks in children. This research introduces a novel spectrofluorimetric method for detecting KTF in its tablets and human blood plasma samples (spiked with KTF). The detection mechanism is based on a photoinduced electron transfer (PET) inhibition spectrofluorimetric approach for the sensitive detection of KTF different samples. By protonating KTF with 2.0 M acetic acid, the PET process is effectively inhibited, leading to a significant enhancement in the fluorescence intensity of KTF at 392 nm. This method detects KTF at values from 50 to 500 ng mL^-1. The technique offers excellent detection and quantification limits of 13.41 and 40.65 ng mL^-1, respectively. The range of the obtained percentage recoveries of KTF for spiked plasma samples was found to be 98.40% ± 1.30%-99.82% ± 1.20%, demonstrating the method's precision and reliability in diverse biological matrices. Also, the approach successfully evaluated KTF content uniformity in tablets without interference.