A digital capture movie-based robotized Flow-batch luminometer for in-line magnetic nanoparticle solid phase extraction and chemiluminescent measurement

The advantages of chemiluminescence, digitally captured movies, magnetic solid-phase extraction (MSPE) and a robotized Flow-batch system were united to develop a new automated luminometer. This digital movie-based robotized Flow-batch luminometer was successfully applied for in-line MSPE, and sensitive, selective determination of Cu2+ in Cachaca (a distilled spirit made from fermented sugarcane juice). Magnetic Fe3O4@Al2O3 nanoparticles immobilized with 1-(2-pyridylazo)-2-naphthol and sodium dodecyl sulfate were employed as magnetic adsorbents. The catalytic effect of Cu2+ on luminol oxidation using H2O2 in alkaline medium was employed to generate the chemiluminescent signals, which were measured via digital movies. The method presented satisfactory analytical features when compared with previous studies, yielding: LOD = 7 mu g L-1, recovery rates = 94.8-106.5%, RSD < 1.7% (n = 3) and sample throughput = 11 L-1. The proposed luminometer provides a synergistic union of MSPE, chemiluminescence, digital movies, and robotized Flow-batch system, and envisions further applications in determining various analytes in diverse complex samples.