A Rayleigh light scattering technique based on β- cyclodextrin modified gold nanoparticles for phenytoin determination in exhaled breath condensate

In the current work, a RLS technique based on beta-cyclodextrin modified gold nanoparticles was validated for phenytoin determination in the exhaled breath condensate. It relies on the complexation of beta-cyclodextrins using-OH groups with amine groups of phenytoin which results in an aggregation-induced Rayleigh light scattering intensity enhancement proportional to phenytoin addition. The method shows a linear relationship with phenytoin concentration in the range of 0.005-0.6 mu g.mL-1 with a limit of detection of 0.003 mu g.mL-1. The validated Rayleigh light scattering system is successfully used for phenytoin determination in the EBC of patients receiving phenytoin.