Antonio Segura Carretero, Carmen Cruces Blanco and Alberto Fernández Gutiérrez
A micelle-stabilized room-temperature phosphorescence (MS-RTP) method was developed for the determination of the phytohormone 1-naphthaleneacetamide residues in fortified pear samples. The proposed method is based on the use of a micellar medium obtained by the surfactant sodium dodecyl sulfate in the presence of thallium nitrate as an external heavy atom salt. To avoid oxygen quenching, sodium sulfite solution was used. To establish the optimum experimental variables, a complete and exhaustive statistical analysis of the experimental data by a multivariate optimization approach was performed. MS-RTP spectra were obtained and successfully used to determine 1-naphthaleneacetamide by the established method without further separation, with a detection limit of 25 ng ml-1. The precision (RSD ≤ 2.55%) and recovery (≥ 91.9%) were satisfactory.