Highly sensitive spectrofluorimetric determination of trace amounts of lecithin using a norfloxacin–terbium probe

BackgroundLecithin is found throughout biological systems. A new spectrofluorimetric method was developed for the determination of trace amounts of lecithin.MethodsOptimum conditions for the determination of lecithin were investigated.ResultsUsing norfloxacin (NF)–terbium ion (Tb3+) as a fluorescent probe, in a buffer solution at pH = 6.80, lecithin reduced the fluorescence intensity of the NF–Tb3+ complex at λ = 545 nm; the reduced fluorescence intensity of the Tb3+ ion is proportional to the concentration of lecithin. The linear range and detection limit for the determination of lecithin were 1.08 × 10− 6–3.02 × 10− 5 mol/l and 2.54 × 10− 7 mol/l.ConclusionThis method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to assess lecithin in serum samples.