High sensitivity spectrophotometric determination of tetracycline with zirconium chelation by employing simultaneous injection effective mixing analysis (SIEMA): tetracycline residue in honey

Abstract A high-sensitivity green analytical methodology was developed for the spectrophotometric determination of tetracycline (TC), employing simultaneous injection effective mixing analysis (SIEMA). This is based on the chelation between tetracycline and zirconium, resulting in a yellow-colored product which exhibits maximum absorption at 420 nm. Under optimal conditions, the proposed procedure showed excellent sensitivity, with linearity over the range of 0.4 to 25 μg/mL. The limits of detection (LOD) and quantitation (LOQ), calculated from 3.3σ and 10σ, where σ is the standard deviation of the intercept, and dividing by the slope of the linear calibration graph, were 0.13 and 0.40 μg/mL, respectively. The recoveries of the standards added to honey samples were 100 to 109%. Application to honey samples was undertaken by the SIEMA method, and compared with a reference method highlighting that the obtained results showed no significant differences at a confidence level of 95%.